New Home Construction

Before the first brick is laid or the first wall raised, you have already established whether you new home will be comfortable, energy efficient and a safe environment for your family.

It’s all in the design.

carrier-acDone properly, you will have efficient equipment and the correct quality and quantity of air flow delivered to every inch of your home. Ronald Smith Heating and Air has over 30 years of proven success in the new construction industry. Here’s what you need to know in order to make an informed decision about the heating and cooling going into your home.

Proper Sizing of Heating and Cooling equipment is essential to indoor air quality, comfort and energy conservation. What does this mean?

First let’s get a few acronyms out of the way. A unit of energy is commonly referred to or defined in terms of British Thermal Units, or BTU’s. Another common term used to define the systems that maintain a home’s living space temperature is Heating, Ventilating and Air Conditioning, or HVAC.

Now that we have that out of the way, let’s get to why size matters.

Size Matters

For every 12,000 BTU’s needed to maintain your home’s indoor temperature, you need 1 ton of air conditioning (AC). So, if you live in a home that has one AC unit that is 5 tons, then theoretically an HVAC professional calculated that your home needed 60,000 BTU’s to maintain comfort. The million-dollar question is whether that professional took the time to really calculate the load, or did they simply use a rule of thumb approach. Worse yet, did they upsize your unit by one or even two tons to give you some “extra capacity” to ensure you would be able to stay cool. Since every ton more typically costs about $1500, extra capacity equals extra profit.

A study done by Pacific Gas and Electric Company, the largest utility provider found that 53% of air conditioning units examined were a full ton oversized. So, over half the time the HVAC professional put in too much and the buyer paid for it. The cost factor is one problem, but it is more than that. When AC units are oversized, they run in shorter cycles, as it doesn’t take as long for the unit to cool the home until the thermostat turns the unit back off. This is known as Short Cycling.

Short Cycling

carrier-cutawayThe problem with short cycle times is that one of the primary jobs of the AC unit is to dehumidify the home. Air conditioners are very inefficient when they first start operation. It is far better for the air conditioner to run longer cycles than shorter ones. The efficiency of the typical air conditioner increases the longer it runs. The ability of the air conditioner to remove moisture (latent capacity) is lowest at the beginning of the air conditioner cycle. The moisture removed from the indoor air is dependent upon the indoor coil temperature being below the dew-point temperature of the air. The moisture then wets the indoor coil and, should the unit run long enough, will begin to flow off the coil and be removed out of the condensate drain.

For short cycles, the coil does not have time to operate at the low temperature and when the unit stops, the moisture on the coil evaporates back into the indoor air. Thus, in humid climates, a properly sized air conditioner will do a far better job of removing moisture from the air than oversized units. An oversized air conditioner cannot remove enough moisture from the air and a home can become cold and clammy.

In addition, mold needs water to grow. Humidity provides water in the air and the more humidity you have in a home the more mold can prosper. When a home is over 65% relative humidity or above mold has an environment to grow. As the humidity rises the environment only improves for mold growth. So, not having an AC unit run for longer cycles is more than just about energy or comfort. It’s also about health.

Given all that we know about indoor air quality and comfort, it’s amazing that the problem of over sizing AC equipment is so pervasive. The Air Conditioning Contractors of America (ACCA) have published the standard for performing load calculations, known as Manual J. When you consider that every house built is unique and that every choice in the house affect efficiency and BTU load, you can imagine how challenging such a calculation can be. As a result, it’s not surprising how many contractors use the rule of thumb approach.

There are a number of software programs that have been created to make this potentially complicated process much easier for HVAC contractors. However, as demonstrated in the PG&E study, these tools are all too often not used and the homeowner pays the price in energy costs, installation costs, comfort and health.

This problem only grows as standard construction requirements of our building codes continue to emphasize more efficient structures. Today the wall and ceiling insulation minimums and minimum efficiency ratings on HVAC equipment have all been increased.

Robert Smith was very personal, and knowledgable. Finished in a timely manner. The whole crew was very polite. Installation was done very quickly and professionly. Alan was very thorough, friendly, polite and professional. Overall, they did a GREAT job and would recommend them in a heart beat.
– Gary J., Powder Springs

In just the last 10 years the increases in the building codes alone have stepped up minimum efficiency ratings of AC units by 30%. Add to this the emphasis in the market place and the tax credits for programs like Energy Star, and the problem only grows further, unless those builders and HVAC contractors are keeping up with their expertise on how to size their equipment.

A little knowledge goes along way. If you are considering building a new home, ask the right questions. It isn’t just about how pretty the finish is. If you are going to make one of the largest investments of your life, shouldn’t it be more than just pretty? Shouldn’t it operate as good as it looks?

control-setup-couple-150x150Many times in our lives, we have to rely on professionals to make decisions that will impact us into the foreseeable future. This is one of those times. At Ronald Smith Heating and Air our highly trained management team will work with you every step of the way to insure that your new building project goes smoothly and is a success. We will work with you to design, suggest, and incorporate the best system for your new home.

Ask us a Question or Schedule an Appointment

If you are looking for an experienced, professional HVAC contractor to help you make the best choices with your building project, please call us today at 888.976.6764 or schedule your service online today!

Did you know?

Did you know that Ronald Smith Heating & Air not only can also handle new housing development construction?

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