For an HVAC Piping & Plumbing Estimator the need for quick budgets for the installation of piping is best handled with a matrix of different material types and sizes. Having an estimating software program can make this process a lot easier as the material pricing is always up to date and can be entered into the matrix quickly.
Often the requirements of the RFP or bidding instructions will call for the price per foot to install piping beyond that which is required by the contract drawings. Such pricing maybe used for change-orders. Having these numbers available and updated often also gives you a quick reference for budgeting projects. It’s good to know when doing job site comparisons of different piping options or during discussions with engineering, what the cost is for the various piping sizes and types of materials.
COST PER FOOT
The cost per foot for the installation of piping needs to include fittings and hangers prorated into the value. It’s best to look at a standard length of pipe and then figure that you will have a Tee and 90 degree elbow in that length. So for example, using twenty feet of copper water pipe with a Tee and 90 degree elbow plus the hangers to build a unit price would represent a field condition of a fitting every ten feet. For higher density projects like Hospitals you could put more fittings in your unit pricing. Total those cost up and then divide by 20 to derive at a cost per foot for that particular size and material type.
20 feet of pipe + 2 Fittings + 3 Hangers / 20 = Cost per Foot
If the piping is insulated, you can also put the values in for insulation.
The Estimating Wizard provides two spreadsheets for tracking unit pricing, one for HVAC Piping and the other for Plumbing piping. Get a copy and start tracking your cost per foot, or be prepared to give a quick budget based on your knowledge from your spreadsheet of unit prices. Watch the video on the estimating Wizard website and see how quick and easy it is to track the cost per foot for various sozes and material types.
MEP Academy HVAC Piping Unit Pricing Calculator
The MEP Academy provides a spreadsheet that makes calculating unit pricing simple. The spreadsheet is available on the MEP Academy website https://mepacademy.com
In the screenshot above there is a place for you to build your hanger requirements (#1), and a place to put your tax rate and hourly labor rate (#2).
For each size of pipe and material type you would insert the unit cost for Material (#3) and Labor (#4).
Under item (#5) you would build your typical run of pipe and enter the quantity of fittings you might expect for the type of building and system. You would add whatever you think will be required for every so many feet of pipe. In the example above we are showing that for every 20 feet of pipe you will have 1 Elbow and 1 Reducing Tee.
Under item (#6) you would add the cost per lineal foot for insulation if required. You could also look at insulation as a separate value and leave the pipe bare.
Line item (#7) is where you indicate the hanger spacing, and for each hanger you defined under item (#1) you will get the quantity as defined by the linear feet in item (#5) divided by your hanger spacing, which will affect your cost.
Line item (#8) is the calculated cost per linear foot of piping for that size and material type of pipe.
After you have all your unit pricing information inputted into the spreadsheet, all you have to do to get a budget for installing piping is to enter the quantity of piping (#9) for each size and material type (#10). The system will automatically calculate the cost (#11) to install that run of piping based on your unit pricing data. The total cost will be shown at the top of the spreadsheet (#12).
The proper sizing and layout of condensate drain lines is important for the protection of property and for the proper functioning of the air conditioning equipment.
Condensate Drain Pipe Sizing
The size required for the condensate pipe is dictated by the local code. Enclosed you will find the requirements for many local codes, but be sure to check your code for your local requirements. If the outlet size of the equipment’s condensate drain is larger than what’s shown in this chart then your required to use the larger outlet size.
Slope to be at least 1/8” per foot or 1 percent, that is for every 12” horizontally there must be at least an 1/8” drop vertically.
Attics or Furred Spaces
If the Air Conditioner is suspended above an inaccessible ceiling, such as a gypsum board ceiling or attic space then you will need to provide a means for protecting the building elements from the overflow of the primary drain and for indicating that there is a leak.
Also, drain pans that are poorly drained can cause water to stay in the pan risking the possibility of algae and bacteria growth. Below are some possible solutions, but as always check your local code for the approved method.
Option 1 – Secondary drain pan with drain piping. This would hang below the Air Conditioning unit in case the A/C units primary pan overflowed. Also, there is a requirement to provide secondary drain piping to a point of termination that would provide notification to the occupants that there is a leak, such as terminating above a window or doorway.
Option 2 – An additional drain pipe connection that sits above the primary drain connection and whereby the secondary drain piping terminates in a location to alert the occupants of the clogged primary drain.
Option 3 – Leak detection device that automatically shuts down the Air Conditioner if the primary drain becomes clogged.
Option 4 – Secondary drain pan with leak detection, located beneath the coil that shuts down the unit upon a leak.
The additional drain pan or drain pan connection shall be provided with a drain pipe that will determinate in an observable area, such as in front a window or above a doorway, and be of a size not less than 3/4”. Secondary drain pan shall not be less than 1-1/2” in height and extend 3” wider on each side of the coil or AC unit.
Video of this Article
Where can and can’t you terminate the air conditioners condensate drain piping? There are several options where you can terminate the condensate drain line;
Condensate Pump to Indirect Drain
Landscaped areas that are properly designed to handle the volume of condensate
To Properly designed stormwater treatment systems.
Lavatory tailpiece in the same tenant space as the air conditioner
Inlet of Bathtub Overflow – Must be accessible
Collect and send to cooling tower (See description below)
The connection to a plumbing fixtures tailpiece has to be made within the same tenant space as the air conditioner cooling coil that is generating the condensate.
A drywell can be used for the termination of your air conditioners condensate drain. Check your local code for the specifics, but generally it includes some or all of the following depending on whether it’s for residential or a commercial project:
A minimum size hole, such as 2 foot by 2 foot by 3 feet deep, or a round hole such as 12” diameter by 3 feet deep.
A minimum of 6” of soil or concrete shall provide cover above the rocks
Some form of barrier between the soil and the top of the drywell where the rock begins, such as building paper or plastic
Drywell to be filled with gravel or crushed rock, often with a stated minimum size rock such as 1 inch diameter
The termination of the condensate drain pipe shall connect indirectly to the drywell drain pipe.
The drywell drain pipe to be a minimum of 1-1/2” PVC or other approved material.
Drywell to be at least three feet away from the building structure or any footings.
There are various methods of providing drywells depending on the local code. There are prefabricated drywells that can be used and ones that are made by using a large diameter piece of PVC pipe or similar material.
Some codes will require you to collect the condensate from cooling coil drain pans and return it to the cooling tower if the equipment is served by a cooling tower and the total combined capacity of the HVAC cooling coils exceeds a certain amount like 65,000 btu/hr. This is a water conservation measure, and there are some exceptions to this requirement, such as if the total capacity of the AC Equipment cooling coils are less than 10% of the total capacity of the cooling tower, or if the location of those AC Cooling coils are in a remote location, far from the tower.
Some locations where you can’t terminate condensate;
Excluded from Code Requirements
Excluded from these codes are non-condensing type of equipment like radiant cooling panels that are designed to prevent condensate from occurring by keeping the temperature of the chilled water above the dew point temperature/vapor pressure of the surrounding air. These are system designed to operate in sensible cooling only modes.
The material types that can be used for condensate drain piping varies by jurisdiction but the most commonly cited materials are:
PVC – DWV
ABS – DWV
Also the use of short radius 90-degree elbows are often prohibited. You can normally use standard fittings until you reach a certain size at which point you might be required to use drainage pattern fittings (DWV)
Traps are to be installed as required per the manufactures recommendation. No traps are required on the secondary drain pan, this is to allow immediate notification that the primary drain has failed.
Cleanouts are required in case of plugged drain pipes. Provide as required to prevent the need to cut drain pipes for unplugging. Some of the following maybe used for cleanouts if approved by your local code authority;
Short clamped hoses at the unit (see image above)
When you have more than one air conditioning unit condensate tied to a main condensate pipe, then every change of direction shall have some method of cleanout. Check your local code as this maybe a requirement for even a single air conditioners condensate piping.
Condensate pumps can be used to elevate the condensate vertically to a point where it will then discharge into a code approved gravity sloping condensate drain line. The condensate pump should be interlocked with the Air Conditioning Unit to prevent its operations if the condensate pump is inoperable.
Please remember that code requirements are always changing, so check for the most current code in your area at the time of design and installation. Or ask an inspector for the current installation practice.
Having an MEP Academy Estimating Spreadsheet that automates portions of your estimates saves you valuable time that you could use to make more sales. All aspects of the cost of furnishing and installing an HVAC or Plumbing system is contained in one spreadsheet made specifically for the MEP industry. New Electrical section coming soon.
Your MEP Academy Estimating Spreadsheet needs to be able to handle rental equipment, general conditions, subcontractors, piping and plumbing takeoffs, sheet metal, labor rate tables with crew mix capabilities, , and a bid summary. Each sheet in the estimating spreadsheet automatically calculates the values you enter, showing you a new total bid amount.
Enter the project equipment price and labor to rig the HVAC and Plumbing equipment into place. Compare supplier pricing easily side by side. The MEP Academy Estimating Spreadsheet automatically selects the lowest bidder but lets you override that decision.
Labor Rate & Crew Mix Table
Choose your crew mix based on the level of experience and the different pay scales based on each project. Pick any combination and quantity of tradesman based on the requirements of the project. There is a separate crew labor rate for HVAC Piping Shop & Field, Sheet Metal Shop & Field, and Plumbing.
Do you need a jobsite trailer or onsite management? Enter the quantity and level of the staff required to run the project, whether one person or dozens. Set the quantity and duration of each general condition, along with the rate. General Conditions is broken down into three sections as follows: #1 – Management, #2 – Construction Office (Non-Reoccurring Expenses), and #3 – Construction Office (Reoccurring Expenses).
HVAC & Plumbing Subcontractors
HVAC & Plumbing contractors often subcontract out for Air & Water Balance, Sheet Metal & Piping Insulation, Water Treatment, Building Automation, Excavation and other specialty trades that they don’t self-perform. This spreadsheet was made especially for the HVAC & Plumbing contractor and their most often used subcontractors.
For those contractors that do plumbing the following Plumbing Fixture sheet will give you a place to record your vendors quotes and the labor it takes to install each type of fixture. What is also revealed is the overall cost per fixture.
MEP Specialty Sheets
Each trade has a specialty sheet for those items that aren’t considered equipment or a fixture, but for which there is a cost impact. The MEP Academy Estimating Spreadsheet includes Sheet Metal, HVAC Piping & Plumbing Specialty sheets. We go over specialties in our online estimating certification course.
Material & Labor Summary Sheets
You will find a Sheet Metal, HVAC Piping & Plumbing material & labor summary sheets where all of the other specialty sheets are summarized for your review and last minute edits. Each sheet will be divided between field & shop fabrication work. The first section covers the field installation items.
Field Summary Section
This is where you will put your material takeoff information for the following:
Rectangular & Round Ductwork
This is also where the other sheets that you filled out will be summarized, such as the following;
HVAC & Plumbing Specialties
HVAC & Plumbing Equipment Labor
Each of the field labor summary sheets contain a row to add for the following
Shop Fabrication Summary Section
For those of you that have a fabrication shop, there is a section to add material and labor.
For those HVAC air conditioning and Plumbing projects that require a crane, fork lift, scissor lift or any other equipment that you don’t own but will be required on the project. Having a spreadsheet that maintains a list of the most common equipment you normally rent along with their rental rate will save you time and money while avoiding having to call for pricing on every job.
If you do your own design then you should have a sheet of each of the personnel responsible for spending time on the engineering task. If you’re doing design/build work, but don’t do the engineering yourself, but hire a third party, then you should add some engineering review time. It’s your responsibility to manage your third-party engineer to make sure they design within your cost parameters.
All of your estimates are summarized on the last tab of the MEP Academy Estimating Spreadsheet for easy review. You can quickly scan each of the categories to see where all the project cost has shown up. There is the labor and material summary for HVAC Sheet Metal, HVAC Piping, and Plumbing and another section for Subcontractors, General Conditions, Rentals, etc.
Project Parameters (Metrics)
How much does this project cost per square foot or per ton? How many CFM or BTU’s per square foot did the engineer figure? What is the cost per ton for this project? What is the cost per plumbing fixture? With the easy parameter calculator contained on the summary page, you can keep historical records of the project you bid.
Bid Risk Assessment Form
The MEP Academy Estimating Spreadsheet contains a bid risk assessment form that rates the success of winning any particular project that you are contemplating pursuing. The risk assessment form will help you determine if the project is worth bidding based on a set of questions that rate your answers.
The answers to these questions will give you a score from which you can use to see how the project rates on a scale of risk and reward. The total risk assessment score will also inform you which level of approval is required within your company depending on how you rate your risk values as the example shown below. The total score is 25, which according to this contractor would require the Vice President to sign-off on the project or approve the decision to pursue bidding on the project.
MEP Academy Estimating Spreadsheet Summary
The MEP Academy Estimating Spreadsheet is used to gather all the information for estimating a project, putting it into a format where you can make quick adjustments and decisions while the spreadsheet gives you an immediate update on the price.
Purchase this spreadsheet at its currently reduced price of ONLY $295.00, which usually sells for $599.00
Watch the YouTube video below to see the MEP Academy Estimating Spreadsheet in action.
What is IPLV (Integrated Part Load Values)? It is based on part load chiller efficiency values. The IPLV is calculated on the weighted percentage of assumed operational hours at each operating condition. So there are four operating points that are going to be measured. This is an average efficiency of a single chiller. A lot of chiller installations will have multiple chillers. So this is a rating for a single chiller.
The IPLV formula is one over the four operational points that we are calling A, B, C & D. These will be the efficiency of the chiller at the different partial loads, which we’ll get into next. Were going to take condition “A” at 1%, condition “B” at 42%, condition “C” at 45%, and condition “D” 12%. This means that the chiller runs at condition a 1% of the time and 42% of the time at condition “B” and so on.
So what does “A”, “B”, “C” and “D” stand for? We are going to take these four data points for the chiller under review. Data point “A” is 1% of the chiller conditions running at 100% full capacity. The four data points are as follows:
Four Data Points Used in IPLV Calculation (EER)
“A” 1% of the time Chiller is running at 100% Capacity
“B” 42% of the time Chiller is running at 75% Capacity
“C” 45% of the time Chiller is running at 50% Capacity
“D” 12% of the time Chiller is running at 25% Capacity
These values will be put into the calculation
“A” = COP or EER at 100% Capacity
“B” = COP or EER at 75% Capacity
“C” = COP or EER at 50% Capacity
“D” = COP or EER at 25% Capacity
So, when the chiller is running at 100%, 75%, 50% and 25% we’ll put in the EER that corresponds to that datapoint.
Step 1 is to determine Part-Load energy efficiency values for the chiller running at these four datapoints as discussed previously as 100%, 75%, 50% and 25% load. These operating points are the AHRI (Air Conditioning, Heating and Refrigeration Institute) standard-550 conditions. Standard-550 specifies the conditions under which these datapoints are measured.
Step 2 is to insert the four data points into the IPLV formula. So now all you need is a sample of the EER for a particular Chiller that you want to analyze. We have a sample of the EER (Energy Efficiency Ratio) of a particular water-cooled chiller as shown here.
Based on the information obtained from the chiller manufacture as shown in the chart above, we can see that the chiller running at 100% as an EER (Energy Efficiency Ratio) of 0.63, and when running at 50% it has an EER of 0.29.
We take the information from above an insert it into our IPLV formula to derive at the IPLV number.
Remember that the chiller runs at full load only 1% of the time, so in the above example the 0.63 EER goes in the first column of the formula, followed by the EER of the chiller at 75% load and so on. You can see that the chiller has the worst EER at full load capacity and the best EER at 25% capacity. That’s why multi chiller plants may run several chillers at low load than to run one chiller at full load.
Below is a spreadsheet that we made to show various chiller manufacturers and how they compare in their total IPLV (Integrated Part Load Value).
You can see that the IPLV for chiller #1 comes out to be 0.335, while chiller #2 is 0.339 and the most efficient of the chillers is #4 at a IPLV of 0.311
AHRI Standard 550
AHRI (Air Conditioning, Heating and Refrigeration Institute) specifies the operating conditions under standard 550/590 that chillers are rated for as follows. According to AHRI the purpose and scope of the standard is as follows;
1.1 Purpose. The purpose of this standard is to establish for Water-chilling and Heat Pump Water-heating Packages using the vapor compression cycle: definitions; test requirements; rating requirements; minimum data requirements for Published Ratings; marking and nameplate data; conversions and calculations; nomenclature; and conformance conditions.
2.1 Scope. This standard applies to factory-made vapor compression refrigeration Water-chilling and Water-heating Packages including one or more compressors. These Water-chilling and Water-heating Packages include:
2.1.1 Water-cooled, Air-cooled, or Evaporatively-cooled Condensers
2.1.2 Water-cooled heat recovery condensers
2.1.3 Air-to-water heat pumps
2.1.4 Water-to-water heat pumps with a capacity greater or equal to 135,000 Btu/h. Water-to-water heat pumps with a capacity less than 135,000 Btu/h are covered by the latest edition of ASHRAE/ANSI/AHRI/ISO Standard 13256
You can see that the AHRI standard has the evaporator LWT (Leaving Water Temperature) at 44 F and various condenser entering water temperatures (EWT) for the various percentages of chiller loads corresponding to the four data points.
If a chiller is to run at other than AHRI Standard 550/590 conditions then its considered NPLV (Non-standard Part Load Values).
IPLV Calculation is Based on a single chiller. Data shows that 80% or more of the central plants have multiple chillers. This would then indicate that IPLV doesn’t accurately represent multi-chiller plant operating conditions. The use of energy analysis tools will provide a better solution. The use of the IPLV is used to compare unloading characteristics of similar chillers in a situation when there is only one chiller.
A chiller doesn’t run at full load most of the time. Chillers run less than full load most of the time, so this calculation is a better indicator of the chillers most likely operating efficiency.
Basically when you’re bidding a project that requires a bid bond it’s because the owner wants you to guarantee that you’re capable of fulfilling the contract requirements and that you’ll be able to secure a Performance & Payment Bond.
Usually a bid bond will roll into a performance bond.
So, what happens if you back out of a bid where you were the successful low bidder and for which a bid bond was issued on?
If you’re the low bidder and you decide not to execute the contract and you want to backout and you provided a bid bond to bid the project. The owner will file a claim against you and your surety company.
If you’re a small company most likely you put up some form of collateral or personal guarantee. You’re personally and financially responsible for the cost difference for the owner to secure the next lowest bidder up to your bond amount.
So, if you bid a $100,000 and the next lowest bidder was $110,000, and your bid bond was in the amount of 10%, your liability is the difference between your bid and the next lowest bidder, which makes you liable for the $10,000 difference if you decide not to execute the contract.
So, if you back out, you’re liable to your bond company for the claim amount plus attorney fees. So, they can come after you if you don’t pay the claim amount and the attorney fees. Read your contract to determine your liability exposure.
It’s almost better to perform the contract knowing you’re going to take a loss, at least you might be able to mitigate the loss with careful planning and great project management while hopefully there’ll be change-orders allowing you to recover some of the loss incurred on the base bid amount.
Bid bonds are usually in the range of 10%, but can vary depending on the contracting authority.
The bid bond percentage will be indicated in the bid documents.
Again, to reiterate. If you back out and you made a personal guarantee, then your personal assets could be at risk, so you want to read the fine print. You want the bond company to explain to you the terms and conditions of the bond.
Often there will be alternatives to a bid bond, such as submitting a cashiers check, certified check or a money order, or some other asset that can make good on your promise to execute the contract if you’re low bidder. Other assets that might be considered are liquid assets, that is something that can be converted into cash easily.
When are bid bonds required?
Most likely on all your Federal, State and Local Municipality projects.
Are bid bonds required on privately held or funded projects? A lot of project are now requiring bid bonds. We’ve seen as the larger the project gets, the greater the chances there will be a requirement to bond the project.
If you are going to be bidding in the Government sector or within the larger private sector projects than you need to build up your bonding capacity. You can’t just start a company and expect a surety company to issue millions of dollars’ worth of bonds on your behalf unless you back it up with collateral and have established record of completing bonded work, and have the area of experience required to complete the proposed project.
The bonding company will also tract how much bond exposure you have outstanding. This is for any work which is currently under bond coverage, and for which is yet to be completed, releasing the bond of any further risk.
So, how much do bid bonds cost?
For projects over $400,000, the bid bond could be free. If you have a good relationship with your bond company then it’s possible there won’t be any charge. For smaller projects there may be a nominal fee of say $100. It’s possible that they have an annual fee, which covers all the bid bonds you would need for the year. Check with your bonding company to discover how they structure their fees.
What happens if you submit a bid without a bid bond on a project that requires a bid bond. What will they do? Your bid will definitely be rejected. They will not accept your bid, even if you are low bidder.
What are Performance Bonds?
They’re used to ensure the project gets completed according to the construction documents. The bid bond usually also guarantees that your surety will issue a performance bond if you’re the successful responsible low bidder. Unlike the bid bond, the performance bond will definitely cost you some money. This is where the surety company gets their money, especially if they offered you the bid bond for free. They know that following a successful bid, you’ll need to pay for the performance bond.
Now with a Performance bond in place, what happens if you fail to perform? You’ve gotten this far and have been executed, that is signed the contract and are now required to perform. If you don’t perform then the bonding company will pay to have the project completed. So your bonding company will either payout to the owner or General Contractor whatever it takes to finish the project that you were contractually obligated to finish. The bonding company may pay another company to finish the contract, but they make risk having to pay more than what the original bond amount was issued for.
Maybe you file bankruptcy or something. They will make your surety company pay to complete the project. You can see why the surety companies want to make sure that you have the experience and financial resources required to complete the project that you are attempting.
The penalty is usually 100% of the contract amount.
What are Payment Bonds?
The payment bond is usually coupled with the performance bond. The payment bond ensures that you pay those who provide material or labor on your behalf for the proposed project. They want to be sure that you have paid all your subcontractors, equipment and material suppliers, including all the labor used on the project that the bond was issued for.
How much does a Performance & Payment Bond Cost?
Performance and payment bonds are often issued as one bond except in some locales where maybe it’s just a performance bond.
Bond Rates can vary from less than 1% up to 2% or more depending on the contract amount, your experience and credit rating.
For example, let’s say that you had a construction contract in the amount of $100,000 and your bond rate was $7.00 for every $1,000 of contract. Or stated as 0.7% of the total contract amount.
So your cost calculation would look like this:
Take the $100,000 divided by the $1,000 to get how many thousands there are. As each $1,000 of contract amount will cost you $7.00.
$100,000 / $1,000 = 100 x $7.00 = $700
Take the $100,000 times 0.7$
$100,000 x 0.7% = $700
If you are just starting out then your bond rates will most likely be higher than this amount, but as you gain experience and grow your credit your rate can eventually be lower than this. Check with your bonding company for the rate structure.
How do you Qualify for a Bond?
Small companies may be require to have the owner pledge a personal guarantee. That is the small company owner personally guarantees to reimburse the bonding company for any claims against the bond. So you really want to think this through if you are a small company and are thinking of securing a bond for a project. You want to make sure that you have all your cost covered and you have an experienced team to execute the contract documents, including the funds to pay for the project as often accounts payable will exceed accounts receivables.
So if you’re a small company its possible you’ll have to provide a personal guarantee, and if your married than your spouse might also be required to sign the guarantee. Check with your bonding company or shop around for the best terms and conditions.
Large companies usually qualify based on their credit rating and experience. So until you get some experience and establish some credit behind you, you may have to give a personal guarantee.
In summary the bonds are insurance that you will do what you said you would, and that is, to execute the contract if you are low bidder and pay all those who helped you build the project, whether that was your subcontractors, or the vendors that sold you equipment or materials, and the workers that perform labor on your behalf.
When bidding on a plan and specification project designed by a third party engineer, it’s imperative to read through the specifications for those items that will affect your normal way of constructing a project. Every contractor has a preferred way of building a project based on their own preference for materials and methods which might not line up with what the engineer has specified. So it’s important to read the specifications thoroughly to determine where the specifications differ from your own companies standards, so that you can adjust your price accordingly.
Your company may have a preference for building their ductwork with certain seams and joints according to the equipment in the fabrication shop, or which is owned by the fabricator you purchase your ductwork from.
Knowing what to look for when reading the specifications comes from years of experience, and being familiar with the lexicon used in the trade to describe various materials and methods of construction. An experienced estimator should be able to quickly read the pertinent sections of the specifications to discern any deviations from his company’s standard methods of construction.
Specifications can be provided in book form, electronically or printed, or they could appear only on the drawings. Either way, make sure to read them carefully.
Not everything that is found in the specifications maybe applicable to the project you are bidding, as engineers use templates for their specifications. This means that they most likely purchased a pre-written technical specification which requires them to personalize it for the particular project, but often they are lazy and the specifications are not applicable or mention systems that don’t exist on the bidding documents. But you still must read the specifications as they will become part of the contract and you can be held to anything that is specified.
You need to record or highlight the important section of the specification for referencing during estimating review meetings or for the project manager if you are successful in winning the bid.
When recording the specification number onto any of the forms used for documenting, write out the full spec section description, such as: 23 73 00 – 8, 3.4 A. This identifies specification section 23 (HVAC Trade), section 73 00 (Air Handlers), – 8 (page 8), paragraph 3.4A. This will help you when you need to refer back to that section, saving you valuable time looking for the same section.
If you are using Blue Beam or Adobe Reader, then you can bookmark that page and section in the program. The idea is to record those items that differ from your standards and which will have a cost impact that you need to cover in your bid, in addition to risk factors to be aware of, risk such as liquidated damages. Liquidated damages are assessed against the contractor usually for not finishing the project on the scheduled completion date, and for each day they’re after a daily fine is assessed.
Reviewing the specifications is a very important step in the process of bidding a project. The specifications will set out the requirements of the materials and equipment that you will be responsible for providing along with the methods and standards of construction. This is not a step that you can avoid. There are methods once you become familiar with the layout of specifications, in which to save time by looking where you know the most pertinent information is located, that which has the greatest impact on cost and risk.
Specifications are assembled in three parts as defined below.
Part 1 (General)
Reading any part of the technical section of the specification will begin with part 1, the General section. The general section of the specifications usually begins by giving a description of the scope of work contained within the section of the specification. This may include a brief outline of the equipment or materials contained in that section (see spec below). The requirements for shop drawings or submittals could also be stated in this section. It might also list related work in other sections of the specifications.
Section 1.2 Related Work
In part 1 of the general section of the specifications you will find section 1.2 “Related Work”. This portion covers other areas of the specifications that have related sections, some of which will be within your scope of work and others within other trades that isn’t part of your scope but needs coordination.
Part 2 Products
In part 2 will be the description of the technical requirements of the equipment or material. The performance, ratings and criteria that must be net if a substitute piece of equipment will be allowed. The equipment or material could be referred to by manufacture and model number, or generically described. Acceptable manufactures could be listed, those other than the one on the equipment schedule.
Part 3 Execution
Part 3 is the last part of the specifications and it describes the methods and quality of construction required. It could mention the start and test requirements for a boiler or that the equipment being installed has to be installed according to manufacture suggested methods of installation. It could mention the requirements of adjusting and cleaning of the equipment.
The areas of concern for the sheet metal trade will be the construction standards specified for the air ducts and accessories. You will need to know the thickness of the material required for the various sizes of duct, and what type of seam and joint is mandated.
Often the specifications will cite SMACNA as the construction standard to follow when fabricating and installing the ductwork and accessories. SMACNA is the industry trade association that publishes construction standards in addition to other works related to the industry.
Construction Specifications Institute
Specifications are broken down by sections that correspond to the different trades. The Construction Specifications Institute (CSI) puts out specification division definitions that classify various trades into easily identifiable numbered sections and subsections.
For example under their earlier version there were 16 divisions and the Mechanical Division was specification section number 15. The format was updated to now include 50 classifications of specification sections. Now division 23 is where you will find the specifications for “Heating Ventilating and Air Conditioning” and division 25 for “Integrated Automation”, the specification section for controls. Under division 23 is where you will find the HVAC sheet metal specifications.
Division 23 Heating, Ventilating and Air Conditioning
Within division 23 of the CSI specifications you will find the sheet metal section of the specifications where the information related to the allowable materials and methods can be found. Here are some of the important items to look for in that section of the specifications.
Which duct seams and joints are allowed for round and rectangular ductwork?
Are adjustable elbows allowed on round duct or is a more expensive type required?
Material and gauge of metal required per duct pressure class or system.
What are the hanger requirements, for both the upper and lower attachments?
What are the requirements for thermal or acoustical lining of ductwork?
Type of volume dampers
Are remote damper operators required above inaccessible ceilings?
Is temporary HVAC equipment required, if doing a renovation project?
Duct pressure testing requirements
Duct mounted smoke detectors. Who provides and installs.
Is cleaning of the ductwork required? SMACNA has three levels of cleanliness.
Are cost breakouts or unit pricing required?
What you are looking for in the specifications is for those items that have a cost impact and for the construction requirements that deviate from your company standards of construction.
In addition to the Division 23, it’s imperative that you determine if some of these other project requirements are listed under “General Conditions” of the specifications or are located in the projects frontend documents.
Liquidated Damages. This is a clause inserted into the construction contract that provides for a penalty, usually a stated amount per day for not meeting some aspect of the terms, such as the completion date. ($500/Day)
Project Schedule. The duration of the project is important when considering how much labor it will take to get the project completed within the scheduled allotted time frame. If the project schedule is too short, then you may need to work overtime in order to complete it on time. If the project schedule is for an extended period of time, you might have additional general condition cost, such as jobsite offices and rental equipment.
Bonding. Check to see if a performance and payment bond is required. These add cost to your bid, as your insurer will charge a fee to issue these if you are the successful bidder. These bonds ensure the owner that you will pay your bills to those who provide material and labor for company on behalf of this project and that you perform according to the contract. For large companies this cost will be less than 1% of the total cost of your portion of the construction, and for smaller companies this would most likely be greater than 1%.
Reading the specifications, RFP (Request for Proposal) or other documents related to the bidding of a project, the goal is to identify areas of risk. Once you identify those items of risk, then you can either mitigate, avoid or manage the risk with the foreknowledge of risk identification. Early risk identification is smart business practice as opposed to being surprised during construction that a certain risk wasn’t identified and now has to be dealt with.
There are some projects that will mandate that certain types of personnel be part of the construction team. These could include the requirement to have a full time supervisor, safety manager or Quality Control Expert. Read carefully through the project personnel requirements and whether they need to be full-time.
Listed Manufacture or Equal
Most engineered projects are designed around a certain equipment manufacture as indicated by the make and model number indicated on the equipment schedule. When reading the specifications you will be looking for the “or Equal” reference where the list of approved manufactures are listed.
Specification Review Checklist
You should have a standard checklist that includes the most common items to look for when reviewing the specifications. The checklist provides a convenient reminder of those items that typically can be found to have a cost impact. Record the specification section and page number for quick reference.
Introduction to Sheet Metal Estimating (Free Course)
If you are looking for Construction Estimating Software, the choices are many. I have personally been involved in overseeing an estimating group of 20 plus estimators and can tell you there was no way we could have bid the amount of projects without using some form of mechanical Estimating software. Depending on your budget and sophistication with software there are a lot of choices, but here are some of my thoughts if you are interested in purchasing a program. I will cover the usual cost encountered which vary per vendor, and then we will cover the features that you should ask about. You will also find a free Construction Estimating Software Checklist on our website at www.MEPAcademy.com that you should use when evaluating a purchase.
Construction Estimating Software ranges from the least expensive to the most expensive, which usually correspond to the features and the popularity of the program. Expect to pay anywhere from $3,000 and up for a basic one license/one trade system, but they more than pay for themselves if you plan on bidding a lot of work.
The more licenses you buy the better the discount. Of course you can get simple add-ons for Excel for much less but they won’t have the Features & Onscreen capabilities of the estimating programs covered here. Each trade usually requires a separate license fee, such that Sheet Metal, HVAC Piping and Plumbing would all require a separate license. There are additional fess as described further in this article.
Software Licensing Fee
The first cost is the cost of a software license for each trade, such as a separate fee for Sheet Metal and another cost for a Plumbing/Piping combination license. Additional licenses after the first one should be at a reduced cost. The combination Plumbing/HVAC Piping is a single license and is sometimes slightly higher than the sheet metal license.
The fee covers the right to use the software according to the terms of the license. Cost for a single license range from a few thousand to upwards of $10,000 or more. But don’t be scared off by these numbers because there is something feasible for most size companies.
Labor Database – fee
Most construction estimating programs have the ability to use industry standard labor units published by MCAA (Mechanical Contractors Association of America), PHCC (Plumbing, Heating & Cooling Contractors Association), or SMACNA (Sheet Metal & Air Conditioning Contractors National Association). The database will give you unit labor values for each item and the total labor required for the project based on their published assumptions.
You will then need to know how your site conditions differ from their standard assumptions and from your own historical database of productivity for a similar situation and project. You will make labor adjustments like you have in the past based on experience, such as Linear Feet per Man Day or a factor of the database values. This is a topic that requires its own article, as there are many aspects to adjusting labor.
Remember that if you are a member of one of these organizations then there is probably no cost for the labor units, and if you’re not a member make sure to verify whether or not the price you are paying for the software includes these labor databases as they are considered proprietary information available by license only.
If you plan on using your labor units then this may not be an issue, but it is easier to start with one of these organizations database as they contain thousands of labor units based on industry surveys. The labor databases may cost you in the range of $200 to $1,000 for all three mechanical trades.
Material Pricing Database / Pricing Service – Fee
You will need to pay an annual reoccurring fee for a pricing service, like Harrison Publishing, Trade Service (Tra-ser), or Allpriser (Canada) which provides retail list prices of most major manufactures of pipe, valves and fittings. These companies charge an annual fee, but it is worth it if you do a lot of bidding. The alternative is to get pricing on each bid which is cumbersome and slow if you bid a lot of projects.
Most programs sold in Northern America come with a pricing update service and contain over 70,000 prices for pipe, valves and fittings. Whether it’s the Euro, Yen or Dollar the cost of commodities are constantly changing and you need to have a pricing method to stay current, and there is no easier method then a pricing service company. You will be notified when the next price update is available and will download it automatically from the internet. This fee varies by vendor but expect a range of $500 to $1,400 per year.
You will need to put your discount multiplier for each manufacturer into the program so that you get net prices for your HVAC piping and plumbing materials, as the material database will be based on retail prices. Whoever does your purchasing will know these discount values.
For sheet metal you will most likely need to manually enter the purchase price for round and rectangular ducts and fittings. If you fabricate your own duct work, then databases from SMACNA will have the labor units but you will still need to add the cost of materials.
Software Training Fee
Be sure to find out how much training will cost as this varies greatly from vendor to vendor and could be free if you use the internet. Some software providers will come to your facility or invite you to their training facility. You have to analyze whether it is more feasible to travel your estimators to their facility or pay for them to come to your office to do the training.
If you have training at your office you will need to pay for the trainer’s travel cost which usually includes flight, hotel, car rental and a daily food allowance. But if the training is in your office you can usually have as many of your employees attend without any additional fees.
Training is also available over the internet through various vendors, which saves a lot on travel cost. Be sure to find out the cost per person and per trade for those that do multiple trades. Some vendors provide unlimited training, so be sure to inquire about this very important aspect of your purchase.
The fees for training depend a lot on which training method that you implement, for web based training there should be no charge or a reduced charge, for training in their facility you should expect a range from $1,000 to $2,500 per estimator, and for training at your facility expect to pay in a range of $3,000 to $7,000 including the trainers travel expenses.
Technical Support and Maintenance Fees
Most construction estimating software vendors have some form of technical support for their program and it is usually included in your annual maintenance fee. This fee is for any upgrades that might occur during the year and for technical support that you may require.
If you choose not to pay for the annual maintenance and support fee, then check to see if they have an hourly rate for when you might need support. This is an annual reoccurring expense that is based on the quantity of licenses that you purchase, also check to see if the first year is included in your software cost, either way you want to know what your cost will be for each year after the first.
From our experience this fee varies greatly by vendor and is based on how many licenses you initially purchase, and can range from 5% to 15% of the license fee. The fee is more towards the lower end of the range the more licenses you own, hence the more negotiating power you have. Make sure to renegotiate this fee if your company grows and you add more licenses.
Total Software Cost Summary
The total cost for the construction estimating software will be composed of at least the following minimum cost range (Remember this is the most versatile of the estimating software the industry currently has, and there are less expensive alternatives with fewer features);
Software Licensing Fee ($2,000 – $10,000 per License/Trade)
Labor Database Fee ($200 – $1,000)
Material Pricing Database Fee (Annual Fee $500 – $1,400)
Training Fee (free – $7,000)
Technical Support Fee (annual fee of 5% – 15% of license fee)
One of the biggest benefits for those who have a detailing department, is the integration with various CAD programs and shop fabrication equipment.
This allows you to share one database and guarantees consistency from estimating to detailing to fabrication. This makes for a huge labor savings because when the detailing department finishes laying out the project, the CAD software program can export a file that can be imported into the construction estimating software program which will execute an estimate without any time spent doing a takeoff.
Ask if this feature is available with the construction estimating software and which CAD/BIM programs its compatible with.
Shop Fabrication Integration
There are many construction estimating software programs that now integrate with shop fabrication equipment, especially for sheet metal.
The program shares an integrated database that keeps consistency between the estimating department, detailing and the fabrication shop.
The program would allow the estimating takeoff to be downloaded to the shop equipment for direct fabrication. In most cases you would want this to come from your detailing department to make sure what you fabricate will actually fit in the space allocated on site. Ask your software vendor what fabrication equipment if any the program is compatible with.
One of the great benefits of estimating software is its ability to provide equipment connections of various sizes quickly and with updated pricing. An assembly is all the pipe, valves and fittings around a piece of equipment or fixture.
For example, a Chiller or Pump often requires the same pipe, valves and fittings whenever one is installed, so why repeat taking off the same bill of materials when an assembly in the construction estimating software can retain all those parts for you. All you do is ask for a chiller connection of a particular size and the software calculates the bill of materials with the latest up to date pricing and includes all the labor for those parts. The same for a typical diffuser connection as shown above. On large project you could have hundreds of these connections. By having an assembly built, you safe time not having to re-enter the same times over and over again.
Ask your vendor how many pre-built assemblies come with the program.
Estimating Reports and Spreadsheets
The estimating software has the ability to run many different reports, from material and labor summaries to isolation of separate zones or alternates for review. The important thing is that if you have a special way of reviewing material and labor summaries and breakdowns.
It’s important to make sure that the software is capable of giving you reports the way you desire. You can pay to have the estimating software vendors make custom reports for you the way your company likes to see them, if the reports don’t give you what you want..
Most of the estimating software programs also come with a spreadsheet for the summation of the information coming from the database from within the software, and for which you will add additional pricing to comprise a total bid.
To the spreadsheet you will add subcontractor pricing, equipment and specialty items not included in your estimating software. The estimating software might also export data that you would then import into another program like Excel. Ask about the versatility of the reporting capabilities.
Some of the estimating programs have the ability to export the information from the estimating software program directly into your proposal application like MS Word. Along with project information there is also the insertion of charts and estimating data.
Sheet Metal – Construction Standards
Contained in the sheet metal estimating program should be rectangular, round and oval duct with the capability to setup any wildcard duct system, such as fiberglass, stainless, black iron and aluminum. The construction estimating software Sheet metal construction standards setup in the database may vary from how you fabricate and breakdown duct sizes in the way of seams, joints and reinforcement.
Part of your implementation time will be spent setting up these standards according to the way you fabricate ductwork. The system should at least come setup with static pressure classes from minus two (-2) to positive six (+6) inches of static pressure.
The construction estimating program should also contain the capability to either enter values for shop fabrication or for the purchasing of ductwork. Ask which pressure classes come pre-setup.
HVAC Piping – Construction Standards
Construction Estimating software programs contain many different piping material types that can be combined in various size breaks, such as using copper up to 2” and carbon steel from 2-1/2” and up, all setup under one system, such as Chilled Water, Heating Hot Water or Condenser Water.
The question to ask is how many systems come pre-setup and which ones? If you use various other types of materials like Polypro or Press-fit type fittings, be sure to ask if they are available in the database. Often times if they haven’t been setup already this will create extra time to implement the system for the type of materials you commonly use.
Plumbing – Construction Standards
The mechanical estimating software will also have many piping materials that can be combined to comprise the required systems for plumbing, such as copper, cast iron, plastics, ABS and others. The same questions apply here as for the HVAC piping construction standards above.
Automatic Generation of Fittings, Hangers and Joints
Forget about counting hangers as the software will automatically provide hangers according to the hanger spacing set in the construction standards. All you need to do most often is to indicate what the upper attachment will be fasten to, such as concrete, wood or steel beams.
Another great feature is the automation of fittings and joints including all the parts that comprise a joint. No more worrying about or having to remember what is required each time you make a fitting or joint connection.
Once your setup, or confirm that the database holds the correct information for the materials you use on your standard fittings and joints, the system will provide a hanger per the hanger schedule in the software, and all the required components surrounding an elbow, tee, joint or connection without you having to tell the system where the fitting is or the parts needed. This makes for extremely fast take-offs because there is no need to take-off each individual fitting. Ask your mechanical estimating software vendor if this feature is available.
Onscreen capabilities allow you to do takeoffs directly from digital plans on your computer screen, reducing the time and cost of printing and manually marking paper copies. The On-Screen digitizer supports a wide variety of popular CAD formats in addition to the following; PDF, JPEG, TIF, GIF, PNG and many others. Here is the Trimble AutoBid Mechanical for taking of HVAC piping. It will give you an idea of how Onscreen takeoff works for the other mechanical trades and estimating software vendors.
Check with your vendor to make sure the program accepts your file types. The program should allow real time panning, zooming and marking of very large CAD drawings while minimizing the impact on the computers performance. On-screen takeoffs has moved away from the use of digitizers, computerized table tops.
Having this feature allows you to switch the specification of your takeoff with another specification type without having to input each item into the system over again. For instance, if you took off everything as being copper, then with this feature you could just swap out the copper construction specifications with any other specification, like black iron, carbon steel, or some form of plastic.
Some of these mechanical estimating software companies offer mobile applications that are compatible with their main program. This allows you to do a field takeoff and then import a file into the main estimating program back at the office. Ask about this feature and its cost and capabilities.
They may integrate with Apples iPad or an Android, be sure to ask.
When you receive changes to the drawings that you have already done a takeoff on, this feature allows the software to compare the two drawings and highlight or indicate the differences. This saves time when addressing addendums and change-orders.
This is one area where you may find that some of them are lacking, as it takes considerable effort to put together and keep updated documentation of the functionality of the mechanical estimating software.
Many vendors now have videos online and don’t provide any written documentation. Be sure to ask about the type and amount of documentation available. Having the ability to refer to training videos or documentation is helpful when you want to learn more about the programs capabilities or just for troubleshooting a simple problem before calling technical support.
Some construction estimating software programs have the capability to export data to various accounting software programs. This is useful if you want to save time in setting up a project for the construction department for labor and material tracking. Having the ability to export all the material and labor values from your estimating program broken down by zone, floor or system type is a convenient and fast way to transition a successful project from estimating to operations quickly.
It’s important to make sure that your accounting software is on the estimating software’s list of compatible programs if this is important for your company. Its possible also that the estimating software can export into Excel or a commonly used format like CSV or a ODBC Compliant file.
Project Scheduling Integration
Again another feature that can be useful if you want to export data into other programs, in this case scheduling software like MS Project. This is another time saving feature that is beneficial for those that provide construction project schedules in the various scheduling programs available.
Network based or Standalone based License
Licensing comes in various forms for the different methods of your company’s IT setup and estimating accessibility requirements. If there is just one estimator, then the question comes down to whether you want the program to reside on a network server or the Cloud which is accessible from many locations or if the program will reside on your laptop or desktop and be accessible to just yourself (Stand alone).
Often with a Network based installation it doesn’t cost anymore if you have one or ten estimators connected to the network software license, because the cost is for the quantity of licenses, not the quantity of estimators. If you have four estimators and only one license, then only one estimator can use the software at a time, and you only pay for one license. You have to evaluate how often the estimating software will be used and for which trades.
Be sure to verify that your current computer has the required specifications to handle the requirements of the construction estimating software program. With the increased functionality and graphics used with some of these programs you want to make sure that your computer can keep up, especially if you are using a network license with many users in different locations.
If using a network and you have users in different cities or locations all using the same server to retrieve the Estimating Program, be sure you have the band width to handle the data transfer required. Make sure to ask all the pertinent questions before purchasing any construction estimating software.
Implementation of the Program
It takes considerable effort to get the program setup to match your company’s way of doing business. Most programs come setup with the basic construction standards, but if yours differ you’ll need to spend time implementing changes to match your company’s’ way of building projects. Whether you do sheet metal, HVAC piping or plumbing, there are construction standards that come prepackaged with most software programs.
Often SMACNA standards or something similar for sheet metal fabrication will come preset and will need to be adjusted for any local code variances in joints, seams, gages or reinforcement. HVAC piping and plumbing will have copper, cast iron no-hub, plastic, carbon steel and refrigeration piping already setup, but once again you have to confirm that it is the same as your company’s construction standards and the local code authority.
Make sure to allow time for implementation. My experience is that most construction estimating software vendors understate the amount of time it takes to implement their programs, so I would expect anywhere from 2 to 8 weeks depending on how many systems you need and how close your company standards are to the boxed standards that come with the mechanical estimating software program.
Do you or your estimator have any experience using construction estimating software? Training will be required in the range of 3 to 5 days. Beyond this you will need to invest time implementing and learning the nuances of the program to become efficient at take-offs including time to maintain the database. Anyone that has the basic understanding of computers will learn quickly how to do takeoffs, and someone who understands construction standards will be required as administrator for implementation and liaison with technical support staff.
Estimating Software Checklist
Use the enclosed 6-page Estimating Software Checklist to compare the various estimating software programs and to make sure you ask the right questions. See below for download link for free Estimating Software Checklist before investing in software.
Estimating Software Demonstration
FREE Construction Estimating Software Demonstrations
We recommend that you get a FREE demonstration of the various software programs so you can evaluate your needs against the available features and cost of the different construction estimating software programs.
Estimating Software Vendors
Software Buying Checklist
For a complete Checklist of the Questions you should be asking any construction estimating software vendor visit the www.MEPAcademy.com for a FREE copy. Look for the download link at the bottom left of the below document screen.
A labor database contains units of labor for each task that is required for a particular project. If you are installing sheet metal than you need to know how long it takes to install the air duct based on its size or weight in addition to taking into consideration the working conditions of the project site. It takes more time to install a 60” x 36” duct than a 12” x 12” duct. But how much time does it really take to install either of these ducts? This is where a labor database comes into the picture, as the basis for which you will make adjustments to.
If the company you are working for doesn’t have their own labor database, then there are third-party labor databases available. With the onset of the digital age there are many companies offering their computerized estimating software that contains a labor database, estimating software companies such as Trimble, QuoteSoft, and FastDuct. These companies integrate the labor database of the industry leader in sheet metal standards, SMACNA (Sheet Metal and Air Conditioning Contractors National Association).
The SMACNA labor database provides units of labor for the fabrication and installation of ductwork and accessories in addition to miscellaneous pieces of HVAC (Heating Ventilating & Air Conditioning) equipment. In addition, SMACNA provides education and advocates for various legislation on Capitol Hill. SMACNA labor data is the most widely used labor database for computerized estimating software programs.
RS Means which was purchased by the Gordian Group also has a labor database but you won’t find it used in any of the top HVAC estimating software programs. They publish various books and have an online version of their database which contains over 77, 622 line item units. The RS Means database contains material and labor, not just labor like the SMACNA database. They offer several levels of access to their database, including unit price cost, cost for assemblies, square foot model cost, Union and Open Shop data sets, Life cycle cost estimating in addition to their eBooks and published cost data books.
Maintaining material cost data for construction elements is a daunting task unless you have a supplier that provides you with the information on a timely basis. Prices change over time do to economic conditions such as inflation and the overall competition amongst suppliers. To make sure you are bidding projects with the latest prices in your database you will need to have a system in place to update the prices. This can either be done manually by calling your supplier every several months to get the latest price or submitting a bill of material for each project your bidding on.
If your company is using an estimating software program this becomes a lot easier, but still requires you to periodically check with your suppliers for price changes or changes to their discount multiplier. A discount multiplier informs you how much you can deduct from their published retail pricing.
You will most likely be using a local fabricator for your rectangular and round duct and fittings. There are sheet metal fabrication companies that sell to the local contractors. There are some HVAC sheet metal contractors that have their own shop fabrication equipment and thereby fabricate their own ductwork. Their fabrication shop can vary on the type and amount of shop fabrication equipment they own, which will dictate the type of ductwork they can make. Shop fabrication equipment is expensive and so is the labor to keep the shop running. Having your own fabrication shop allows you to control the quality and timely delivery of ductwork and fittings.
If you are taking off HVAC piping or Plumbing this is automated by several companies that sell material price databases that contain tens of thousands of prices on pipe, valves and fittings. These prices are automatically downloaded from the internet into your estimating software and the only thing you need to do is maintain your discount multiplier for the different manufactures.
For those companies large enough to have a purchasing department or an individual responsible for making purchase, the process of getting updated pricing can be handled through them. They will be in constant contact with your local suppliers and will notify you when prices change.
Introduction to Sheet Metal Estimating (Free Course)
Maintaining a set of estimating standards will create a more efficient estimating department or disciplined estimator. By creating estimating standards you will be able to quickly identify systems from one drawing to the next, and be able to assemble your estimates in the same manner from one project to the next. Estimating standards make reviewing and bidding projects more efficient by having a structured protocol for each step of the way.
System Identification (Color Coding Chart)
When starting a takeoff you must have a way to record what has been taken off and what has yet to be done. This is best done by coloring the portion of the ductwork that has been takeoff. If you’re using an estimating software program, then the coloring or indication of what has been taken off will be automatically done for you. All you have to do is setup the colors per system type, such as VAV High Side, VAV Low Side, Supply, Return and Exhaust air systems.
It’s also important to color each system a different color, as this will help you quickly identify a system by its equivalent color code. For example; Low Pressure Supply Air would always be colored light blue, while return air would be colored orange. By following this simple rule of coloring from one drawing to the next, it will make it easy to view drawings using a visual representation of system types.
These are the standard colors we will be using through-out this training. It is also helpful for those that may not be familiar with your color coding, to put a legend on the drawing as shown in the picture below.
It’s important to color your takeoff as you record the material taken-off, this will ensure that you can quickly recognize where you last left off. It’s also important that you don’t color in any of the material that you haven’t taken off into your takeoff sheet or computer.
Computer estimating programs also use different colors to represent different portions and system types in a material take-off. Your company should establish a standard that everyone uses in order to maintain consistency. After a while you can instantly recognize a system based on the colors that were used during takeoff as we’ll show you below.
High Pressure Supply Ducts
Begin your takeoff at the source of the air, which is often a main duct coming out of a shaft as shown below for this VAV high-side supply duct in a commercial HVAC system. It’s not actually seeing high static pressure, but the nomenclature is used to distinguish the low side from the high-side of the VAV terminal box. The specifications will define the static pressure to be used at various location in the duct system.
The first item at the shaft wall is a tap then a CSFD (Combination Smoke & Fire Damper). Remember that shafts can carry air from one floor to another and will usually require some form of smoke and or fire damper to protect the migration of smoke from one floor to another through the ductwork.
The duct will act as a transportation highway bringing toxic smoke that may occur from a fire on another floor through the shaft, so it is important to be aware of the requirements for smoke and fire dampers. We also know that a Smoke or Fire Damper will need an access door in the duct and another in the ceiling if the ceiling is constructed of inaccessible material like gypsum board.
In this example we will take off all of the High-side VAV Supply main duct and color it pink to indicate the high pressure side. Of course, most likely it’s not high pressure ductwork, but can be anything from +2” sp to + 6” sp. We use this terminology only to distinguish the upstream from the downstream side of the VAV box.
As you can see in the drawing it’s easy to now identify where the high-side supply air duct main runs through-out the building.
When we have finished with the High-side main duct we will color all of the VAV Terminal Units or VAV Boxes with a yellow highlighter. You could also do this in the beginning, while counting how many VAV boxes there are.
This will help us quickly visualize the demarcation between high-side and low-side. The VAV box separates the two pressure classes as often defined by Engineers and the static pressure requirements as seen by the duct.
Low Pressure Supply Duct
After completing the high pressure side takeoff then you can start with the low pressure side of the VAV box. We will use blue as our color for the low pressure side. This will allow you to quickly see where the high and low side start and stop.
Return Air Ducts
After completing the high and low pressure duct takeoff then proceed to the return air system. In this example the return air is not ducted back to the air handler, it is returned through the attic space un-ducted.
What the engineer has shown is sound boots in each office or space so that noise is not transmitted from one office to another through the return air grilles. In this case it appears that each office space has full height walls that would trap any return air, so a means for getting out of the space is required.
Another thing to consider is that engineers are not detailing the design drawings and additional fittings will be needed as the drawings are considered diagrammatic. This means that you will need to make some judgment as to where additional fittings will be required as shown in the below picture.
Outlined in the red box in the picture below you can see that the VAV box is at a similar elevation as the main duct. The VAV box is shown in yellow and the main duct has been colored pink. The low pressure duct in blue starts from the plenum of the VAV box and turns and goes back over the main duct without any fittings shown.
It would be impossible to do this if the VAV box and main duct are at the same elevation because that would mean that the low pressure duct is also at the same elevation.
In this case its best to add at least four (4) additional fittings, either 90 degree or 45 degree elbows. This will get you up and over the main duct and then back down over the other side of the main and back down to the starting elevation. If you are changing elevation of the low pressure duct then you can use just two (2) fittings to get you up over the main duct and then remain at that elevation without dipping down back to the starting elevation.
It should now be easy to spot anything that was missed. You will notice any white areas of the drawing that haven’t been colored that may contain a piece of duct.
Sheet Metal Material Takeoff Sheets
Round Duct Takeoff Sheet
When doing manual takeoffs without the benefit of a computer program, you should use preprinted forms or a computer spreadsheet to tally your material takeoff.
Rectangular Sheet Metal Takeoff Sheet
The most common fittings are shown on the takeoff sheet. You can rename any of the fittings that you commonly use in your area. The idea is to make takeoff’s as easy as possible without duplicating efforts.
Sheet Metal Breakdown
A sheet metal takeoff needs to be properly broken down so as to allow for easy labor analysis when you are complete. To do this, you will need to separate ductwork according size ranges that use similar productivity factors, such as is shown in this replication of the Military’s productivity schedule.
As can be seen in the chart above, the sizes are broken down into ranges based on the full perimeter of the ductwork. The perimeter is the same as the stretch-out we discussed in a previous section. If you have a 24” x 12” section of ductwork, then the perimeter (stretch-out) would be as follows;
24” + 12” + 24” + 12” = 72”
This would fall on the first line of the chart for rectangular ductwork.
The chart separates rectangular duct into different size ranges. All rectangular ductwork that ranges in size from 20” to 94” in total perimeter, equals 2.38 Linear Feet per Hour or 19.05 Linear Feet per Day. This would equal any ductwork where the perimeter or stretch-out length fell within those values, such as; 22” x 24” ductwork, which when stretched out equals a 92” perimeter (22” + 24” + 22” + 24” = 92”)
Zone, System & Size Breakdown
When doing a sheet metal takeoff, it’s helpful to separate the takeoff according to the following;
Drawing # (M-1, M-2)
Zone (AHU-1, or AC-5) Air Handling Unit #1 or Air Conditioner #5
System (Supply, Return, Exhaust, Relief, etc.)
By breaking out your takeoff in a structured way like this, it makes it easy for labor analysis and addendum modifications. Your takeoff might be organized as follows;
M-1, AC-5, Supply Air.
M-1, AC-5, Return Air
M-1, AC-5. Outside Air
If a week later an addendum was issued that changed the ductwork on AC-5, this would be an easy change for you since you have isolated it within your takeoff.
Starting the Takeoff
It’s best to start at the source of the air being provided into the duct. This could include an Air Handler, Air Conditioner, Fan or just the most upstream section of the ductwork, where it is at its largest dimension and CFM capacity.
Estimating Review Meeting
Depending on the size of your company there will be varying amounts of individuals participating in the estimate review. For a small company this could fall squarely on the owner or the estimator. For larger companies, the estimate review meeting could include field supervisors, estimating managers, salespeople and other decisions makers. The larger the project, the larger the potential estimate reviewers involved.
For this estimating review meeting, be sure to have copies of the labor reports for all those who will be attending, along with a copy of the sheet metal specialties sheet. Be organized and professional at all times, this is where you establish your credibility as an estimator, by the way in which you present yourself and your estimate.
Estimating Sign-Off Threshold Amounts
Some companies will establish threshold for sign-offs of the estimate based on the dollar amount of the bid. For project greater than a million dollars, maybe your estimating standards would require that the bid be reviewed and signed by an executive of the company. The more difficult the project, the more you want to get an experienced opinion of others.
Example of Threshold Sign-off Authority
Estimator $0 to $250,000
Estimating Manager $0 to $500,000
Vice President $0 to $2,000,000
Owner. President $0 to Infinity
Project Kickoff Meetings
When a project is successfully won and the project documents have been handed over to the construction department, there should be some form of project kickoff meeting. During this meeting the estimating team or individual estimator would explain the approach to the estimate and the values of the estimate.
At this point in the process, the estimator is usually the one most intimate with the project scope and details, so is one of the best to communicate all the information about the project. The project kickoff meeting will ensure that key information is transferred to the team that will be responsible for building the project.
Project Closeout Meetings
It’s also good to have some form of project closeout meeting, or lessons learned feedback so that anything of significance learned while executing the construction of the project can be shared with the estimators or estimating department to make them more efficient in future estimates.
Acknowledging where the estimate went over or under the estimated amount will help to make future adjustment in labor or material values as required to bring each category of the estimate in alignment with the actual cost. Realizing that labor is always going to be the biggest variable, this is an area for continuous study to better understand how your company performs in various environments and conditions.
Double checking your calculations and having a second set of eyes review the bid and proposal will help eliminate possible errors. Your company should have some measure of ensuring the accuracy of your bids. This can be by using estimating software, bid review meetings or several people reviewing the bid and proposal for projects exceeding a certain dollar value.
Establish estimating standards for your company so that as you grow there will be a way to have all your estimates uniformly arranged. This will make it easier and quicker to review and audit estimates.
Estimating standards will provide consistency from one estimate to the next. This includes using one estimating spreadsheet that gets updated as things change, but which mostly remains consistent from one estimate to another.
Introduction to Sheet Metal Estimating (Free Course)
The MEP Academy provides articles, training and information for the HVAC, Electrical and Plumbing Industry. Engineers and contractors in the commercial construction industry will find useful information to help them do their jobs.