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Wednesday, November 20, 2024
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Construction Estimator

MEP Academy Instructor
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Construction Estimator

Welcome to our article on the exciting field of construction estimating! If you’ve ever wondered what goes into determining the cost and planning of construction projects, you’re in the right place. In this article, we’ll dive into the essentials of becoming a construction estimator, including the educational background you’ll need to get started, the salary you can expect, and the current job market outlook. Whether you’re considering a career change or just curious about the role, stay tuned to learn everything you need to know about this vital profession in the construction industry.

If you prefer to watch the video of this presentation, then scroll to the bottom.

A construction estimator plays a crucial role in the planning and budgeting stages of construction projects. The first thing most candidates want to know is how much does a Construction Cots Estimator make?

Expected Pay

As of May 2023, non-residential construction cost estimators in the United States earn a competitive salary, with the U.S. Bureau of Labor Statistics reporting an annual mean wage of $94,430. This figure reflects the critical role these professionals play in accurately forecasting the costs of large-scale construction projects, ensuring that budgets are realistic and that projects are completed efficiently. With experience and expertise, many estimators can expect to earn well above this average, particularly in regions with high demand for construction services. What does an estimator do every day?

Construction Estimator Job Duties

  • Review project plans, specifications, and drawings to understand the scope of work and project requirements.
  • Calculate the costs of materials, labor, equipment, and other expenses involved in the project. This often involves creating detailed cost estimates and budgets.
  • Prepare and submit detailed bids or proposals to potential clients or contractors. This includes gathering quotes from subcontractors and suppliers.
  • Measure and quantify materials, labor, and equipment needed for the project from blueprints or design documents.
  • Identify potential risks and challenges that could affect the cost or timeline of the project. Propose solutions or contingencies to address these risks.
  • Monitor and manage costs throughout the project lifecycle to ensure that the project remains within budget. This includes analyzing and adjusting estimates as needed.
  • Work closely with project managers, architects, engineers, and other stakeholders to ensure that estimates are accurate and reflect project requirements.
  • Stay updated on current market rates for materials, labor, and equipment to ensure that estimates are competitive and realistic.
  • Maintain detailed records of estimates, bids, and project changes. Prepare reports and documentation for review and approval.
  • Review and analyze contracts and agreements to ensure that they align with the estimates and scope of work.

Estimators need strong analytical skills, attention to detail, and a thorough understanding of construction methods and materials to perform their job effectively. What type of education is required?

Education

For those looking to break into the construction industry as a cost estimator, pursuing an expensive four-year college degree which can range from $30,000 to over $100,000 isn’t the only path to success. Instead, consider enrolling in the MEP Academy Construction Estimator course, which offers a targeted, practical education at a fraction of the cost and time commitment. 

This course can be completed in less than six months for around a thousand dollars. This will provide you with specialized skills that are directly applicable to the HVAC and piping industries. By focusing on the specific knowledge and tools needed for this niche, the course equips you to enter the workforce quickly and efficiently, without the burden of student debt. Additionally, the online, industry-specific training offered by the MEP Academy is designed to meet the current demands of employers, making you job-ready upon completion.

In contrast, a four-year degree often involves general education courses that may not directly contribute to your career as an estimator, extending your time in school and inflating costs. With the construction industry increasingly valuing practical experience and specialized skills, the MEP Academy course offers a streamlined, cost-effective alternative that prepares you for a high-paying, in-demand career in a fraction of the time. What are some of the qualities of a good estimator?

Construction Estimator Qualities

The following are some of the qualities of a good estimator.

Analytical skills: Cost estimators need strong analytical abilities to assess various construction and fabrication methods, identifying the most cost-effective options.

Attention to detail: Precision is crucial for cost estimators, as even minor inaccuracies can significantly impact the overall budget of a construction project.

Mathematical proficiency: Excellent math skills are essential for cost estimators to accurately calculate labor, material, and equipment costs for construction projects. While mathematical proficiency is important for cost estimators, the widespread adoption of advanced estimating software has significantly reduced the need for manual calculations. These tools automate many of the complex mathematical processes, allowing estimators to focus more on analysis and decision-making rather than number crunching.

Time management: Effective time management is vital for cost estimators, who must plan ahead and work efficiently to meet strict deadlines.

Writing skills: Strong writing skills are necessary for cost estimators to craft detailed proposals that aid upper tiered contractors or owners in making informed contractor selection decisions.

What is the current job prospect for Construction estimator?

Job Outlook

The job outlook for cost estimators is promising, with the U.S. Bureau of Labor Statistics projecting about 18,000 job openings each year, on average, over the next decade. The steady demand is driven by the ongoing need for accurate cost assessments in construction and manufacturing, as businesses strive to manage expenses and improve efficiency.

The profession offers strong opportunities for those with the right skills. As industries continue to grow and evolve, they require precise cost estimation to ensure project success. These figures are inclusive of other categories besides construction cost estimators. The construction industry is one of the largest contributing factors at about 51% of those employed as cost estimators.

Should you Oversize your Air Conditioner

MEP Academy Instructor
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Should you Oversize your Air Conditioner

The question customers often ask, is should I oversize my air conditioner? 

We’re going to show you the difference between an air conditioner that is correctly sized and one that is oversized. 

If you prefer to watch the video of this presentation, then scroll to the bottom.

Customers often think that a larger unit will cool their space more quickly, leading to immediate comfort. While it is true that an oversized unit will cool the air faster, it won’t run long enough to evenly distribute the cool air and effectively remove humidity, resulting in discomfort. 

A Correctly Sized AC Unit versus and Oversized Air Conditioner

Comparison of Correctly sized to Oversized AC

Here we have two air conditioners, one that is sized correctly at 2-1/2 tons, and another that is oversized at 5 tons. When the thermostat calls for cooling, they both turn on. While the larger unit has the capacity to cool twice as fast, the correctly sized unit will run longer to satisfy the space. You may think this is where the advantage of oversizing makes sense by having a larger unit run for less time. We’ll show you why this is a bad idea.

We have added blue colored dots to represent the moisture level and what happens to the humidity or moisture in the conditioned space when the air conditioner is running. When the air conditioner is running, we can see that moisture is being removed from the air as water begins dripping out of the condensate drain line. The drain line is often out of sight of the occupant who is unaware of its existence unless it becomes clogged and causes a problem.

The oversized unit cools the space so quickly that the air conditioner shuts off before removing enough moisture. We can see the correctly sized unit keeps running while the larger unit has shutoff. The smaller unit runs longer, allowing more time for the moisture in the air to meet the cooling coil and condense out as water. The longer the unit runs the more moisture that is removed from the air, making the air less humid and stuffy.

There are many reasons why you shouldn’t Oversize your Air conditioner

Oversizing an air conditioner can lead to several issues that can negatively impact both the system’s performance and the comfort of the space being cooled. Here are some key reasons to avoid oversizing an air conditioner:

Short Cycling

An oversized air conditioner will cool the space too quickly, causing the system to cycle on and off frequently. This short cycling leads to increased wear and tear on the unit, reducing its lifespan and increasing maintenance costs.

Inadequate Humidity Control 

Air conditioners not only cool the air but also remove humidity or moisture. The air contains moisture that isn’t visible to the human eye. Proof of this moisture becomes visible on a hot day with a glass full of ice water. The moisture in the air condenses on the cool outer surface of the glass.

This moisture comes from the surrounding air and not from the ice in the glass. An oversized unit will cool the air so rapidly that it won’t run long enough to remove this moisture or dehumidify the space effectively, leading to higher indoor humidity levels. This can result in a clammy, uncomfortable environment and promote the growth of mold and mildew.

Why is removing moisture from the air so important?

The human body cools itself primarily through the process of sweating and subsequent evaporation of sweat from the skin’s surface. High humidity levels in the environment can slow down the evaporation process because the air is already saturated with moisture. This makes it harder for sweat to evaporate, reducing the cooling efficiency.

Increased Energy Consumption

Frequent cycling and running at a higher capacity than needed will consume more energy, leading to higher utility bills. An oversized unit is less energy-efficient compared to a properly sized one.

Uneven Cooling

Oversized air conditioners can create hot and cold spots within the space. The rapid cooling cycle may not allow the conditioned air to be distributed evenly, leading to some areas being too cold while others remain warm.

Higher Initial Cost

Larger units are more expensive to purchase and install. By properly sizing the air conditioner, you can avoid unnecessary costs and ensure you are investing in the right equipment for your needs.

Environmental Impact

Higher energy consumption results in increased greenhouse gas emissions, which contribute to environmental degradation. Properly sizing an air conditioner helps reduce the carbon footprint of the building.

To determine the correct size for an air conditioner, a detailed load calculation should be performed. Consider factors such as the size of the space, insulation levels, number of occupants, and local climate. This ensures that the system operates efficiently, provides adequate comfort, and maintains a healthy indoor environment.

Should you Oversize your Air Conditioner

Boiler Vent Categories

MEP Academy Instructor
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Boiler Vent Categories

All certified boilers have a uniform test procedure to evaluate the vent system. The vent categories are determined to be either under a positive or negative pressure. They are also categorized by their possibility to condense water from the products of combustion. The ability of the products of combustion to condense into a liquid is related to the efficiency of the boiler. As the efficiency of the boiler goes up, the temperature of flue gases becomes cooler, increasing the changes of condensation.

If you prefer to watch the video of this presentation, then scroll to the bottom of the page.

Boiler Flue Vent Chart

Here we put together a simple vent chart to help you envision the requirements.

Boiler Flue Category Chart - Type I, II, III, and IV, Negative, Positive, Condensing and Non-Condensing Boilers
Boiler Flue Category Chart – Type I, II, III, and IV, Negative, Positive, Condensing and Non-Condensing Boilers

Category I Vents

The most used vent category is category One, which is where you might find the use of Type “B” vent materials. This is considered a non-condensing, negative pressure or negative draft system. Since the products of combustion are hot enough to stay above the dew point temperature there should be no condensate.

Type B Vents

Type B vents are designed specifically for non-condensing appliances that produce high-temperature flue gases not exceeding 400 degrees Fahrenheit. These vents operate under negative pressure, relying on natural draft to expel combustion gases. They are usually used with gas appliances with draft hoods.

Category II Vents

Category II vents also operates under a negative pressure like category I, but the flue gases are much cooler than a category one vent. The cooler products of combustion make the gases susceptible to condensation, so they’re located under the condensing side of the chart. Since condensation is possible, the material of the flue must resist the corrosive nature caused by the presence of moisture.

Category III Vents

Category III vents are considered positive pressure because they use a power exhauster for combustion and venting. Positive pressure vents create a unique risk because they can push combustion gases, including potentially harmful carbon monoxide, into the occupied or living space if there are leaks in the venting system.

Unlike negative pressure vents, which rely on natural draft to pull gases out, positive pressure systems actively force gases through the vent, increasing the likelihood of leakage if the venting system is not properly sealed and maintained. Since the flue gas temperature is high enough to avoid condensation, category three vents are in the non-condensing section of the chart.

When replacing a non-condensing boiler with a condensing boiler, several critical considerations must be made regarding the existing flue system. Condensing boilers operate differently than non-condensing boilers, primarily because they extract more heat from the exhaust gases, causing the gases to cool and condense before exiting the flue. The cooler temperatures my cause water to condense in the vent. 

Category IV Vents

Category IV also uses a forced draft positive pressure vent, but since the flue gas temperatures can reach temperatures below the dewpoint they’re classified as condensing type. The flue will also require that the material resist corrosion caused by the presence of moisture.

Direct Venting

Specialized venting systems, such as direct venting, use sealed combustion to draw air from outside and expel exhaust gases directly outdoors, enhancing efficiency and safety. This system typically consists of two separate pipes for intake and exhaust. Direct vent systems improve efficiency by not using indoor air for combustion and minimize the risk of indoor air contamination. 

In addition to enhancing efficiency and safety, direct venting systems offer several other benefits. They reduce the risk of back drafting, which can lead to the infiltration of harmful combustion gases like carbon monoxide into the living space. Direct venting also allows for more flexible installation options, as these systems can be vented horizontally or vertically, making them suitable for a variety of building layouts.

Furthermore, by using outdoor air for combustion, direct vent systems help maintain better indoor air quality and reduce drafts, contributing to a more comfortable indoor environment. Lastly, these systems are generally quieter and more aesthetically pleasing, with fewer visible exterior components.

Flue Material

A category One vent with a non-condensing boiler flue typically use double-wall type “B” vent materials. The double-wall helps maintain the flue temperature above the condensing temperature.

Condensing Boiler Flues must be made from materials that can resist acidic condensate and moisture, such as PVC, CPVC, Polypropylene, or Stainless Steel. Check the boiler manufacturers data to determine the required material. If converting from non-condensing boilers to condensing boilers then the existing metal flues may corrode due to the acidic nature of the condensate produced by condensing boilers. 

Condensing boilers often require smaller flue diameters due to lower exhaust gas temperatures and higher efficiency. The existing non-condensing flue size may need to be reduced to maintain proper draft.

Condensing boilers produce significant amounts of condensate that must be safely drained away. The condensate is acidic and may require neutralization before being discharged into the drainage system to prevent damage to plumbing and the environment.

Summary

When replacing a non-condensing boiler with a condensing boiler, it is essential to thoroughly assess and potentially modify the existing flue system to accommodate the specific requirements of the condensing boiler. This includes using appropriate materials, ensuring proper sizing and configuration, managing condensate, complying with codes and regulations, and potentially insulating and sealing the flue system.

Boiler Flue Categories Positive and Negative, Condensing and Non-Condensing

Why use Steam

MEP Academy Instructor
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Why use Steam

Why use steam for heating? Steam is an excellent medium for heating due to its unique properties, particularly its specific volume and latent heat of vaporization. Here’s an explanation of why these properties make steam beneficial for heating.

If you prefer to watch the video of this presentation, then scroll to the bottom.

Specific Volume of Steam

Specific volume is the volume occupied by a unit mass of a substance, in this case steam.

Steam has a significantly larger specific volume compared to liquid water. This means that for the same mass, steam occupies a much larger space. When steam gives up its heat and condenses into water, it undergoes a dramatic reduction in volume, because water occupies much less space. 

Specific Volume of Saturated Steam. Increased pressure, reduces steam volume.
Specific Volume of Saturated Steam. Increased pressure, reduces steam volume.

Here we have 1 pound of steam at different gauge pressures. At 0 PSIG our specific volume is the greatest at 26.78 cubic feet per pound of steam. As we increase the pressure on the same pound of steam the volume gets smaller, and smaller. At 15 PSIG the volume is about half of that at 0 PSIG, and if we increase the pressure to 50 PSIG the volume decreases again by about half to 6.68 cubic feet per pound. Boilers are rated by their pressure, with low pressure considered 15 PSIG and less, and pressures over that are considered high pressure boilers.

We can see that if we drop the pressure from 50 psig to 15 psig, the same amount of steam now requires twice as much space or volume. By increasing the steam pressure, we can squeeze the same amount of steam into a smaller space. Now less look at how much energy steam holds at these different pressures.

Latent Heat of Vaporization for Dry Steam

The latent heat of vaporization is the amount of heat required to convert a unit mass of a liquid into a vapor without a temperature change. Steam holds more energy per pound than water. If we first look at water at 32 degrees Fahrenheit and the energy it takes to get that 1 pound of water to the boiling point of 212 degrees Fahrenheit, and then convert that pound of water to vapor we’ll understand the differences. 

Latent Heat of Vaporization for Steam at 0 psig is 970 Btu/Lb

A BTU is the amount of heat required to raise 1 pound of water, 1 degree Fahrenheit. This would require 180 BTUs to raise our water at 32 degrees to 212 degrees Fahrenheit. This means our 1 pound of liquid water at 212 degrees Fahrenheit holds 180 btu’s. We would then need approximately 970 BTU to convert the water at 212 degrees Fahrenheit to vapor at 212 degrees Fahrenheit, there is no change in temperature, just a change of state from water to vapor. The vapor holds 970 Btu’s, while the water holds only 180 Btu’s. This is one of the big advantages of using steam.

Steam carries a large amount of energy due to its high latent heat of vaporization. When steam condenses back into water on the surface of a heat exchanger, it releases this substantial amount of energy, which can be used for heating purposes. This energy release is highly efficient, making steam an effective medium for transferring heat.

Why Use Steam for Heating

The enthalpy of steam does not significantly change with an increase in pressure, which means that the total energy content (including both sensible heat and latent heat) of steam remains relatively constant across different pressures. This characteristic indicates that the efficiency of steam as a heat transfer medium is not primarily due to changes in its enthalpy with pressure. 

Instead, the primary advantage of using steam lies in its high latent heat of vaporization and the efficient heat transfer during condensation. These properties enable steam to transfer large amounts of energy quickly and effectively, making it a preferred choice for heating applications despite the relatively stable enthalpy across varying pressures.

As the pressure of steam increases, its specific volume significantly decreases, meaning that the steam becomes denser and occupies less space per unit mass. This reduction in specific volume with higher pressure allows for the use of smaller diameter piping to transport the same amount of steam energy.

Smaller pipes require less material, which reduces the overall material costs. Additionally, smaller piping is easier and quicker to install, leading to lower labor costs. This efficiency in piping size and installation makes steam systems economically advantageous in industrial and commercial applications.

Efficient Heat Transfer using Steam

When steam contacts a cooler surface, it condenses rapidly, releasing a large amount of heat almost instantaneously. This rapid condensation makes steam an excellent medium for delivering heat quickly and efficiently.

Steam provides uniform heating as it condenses at a constant temperature. This is particularly advantageous in processes requiring consistent temperature control.

Ease of Transport and Control

Due to its gaseous state, steam can be easily transported through pipes over long distances without significant heat loss. This makes it ideal for centralized heating systems where the heat source is distant from the application point.

Steam systems are relatively easy to control using valves and other mechanisms, allowing for precise regulation of heat delivery to different parts of a building or process.

Economic and Practical Considerations

Steam heating systems are often cost-effective, both in terms of initial setup and operational costs, especially in large-scale applications like commercial buildings and industrial processes.

Steam can be used in a variety of heating applications, from space heating in buildings to process heating in industries.

In summary, steam’s high latent heat of vaporization and large specific volume, combined with its efficient heat transfer capabilities and ease of transport and control, make it a highly effective and versatile medium for heating applications.

Why use Steam Heating
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