FREQUENTLY ASKED QUESTIONS

What is Home Performance?

Simply put, Home Performance is exacting quality in every detail. It’s about making the mechanics of your home as beautiful as the finest moldings and finishes. Focusing on comfort and indoor air quality, building and mechanical system durability, and energy efficiency and performance- it’s a science that maximizes and protects your investments, the environment, and your loved ones.

What makes the Energy Docs Home Performance retrofit projects different from everything else?

That’s easy: Delivered Results. With the introduction of building performance test equipment over the past two decades, in conjunction with concerns over escalating energy costs, many scientists, engineers, and building performance folks began testing everything that we always thought we knew about building homes. And you know what we found? Even brand new homes- the ones that we hear and see all of the fancy plaques, stickers and energy efficient accolades about- have huge opportunities for improvement in virtually every category. The HVAC systems are sized and installed incorrectly, the insulation is installed poorly, the water pumping, heating, and distribution systems waste energy, and the homes are ventilated wrong. Of course the same is true for all of the older, existing housing stock in California. True Home Performance is about not making assumptions, but instead testing everything, performing all work to exacting and defined tolerances, and verifying the quality of all installations afterwards. Finally, HP is about ensuring that the long term performance goals were met by occupant feedback and utility bill data history.

Home Performance is about making your home a high-performance energy machine. All of our homes are machines- whether we think of them in that way or not. They consume energy- LOTS of it. And they are a monthly liability that we are responsible for. Did you know that if you don’t pay your energy bill, you cannot legally live in your home? Despite the fact that you own, or are buying your home with a loan, the energy company has the ultimate control over your ability to live in it. It’s the law.

But my home is old!

You’re not alone. There are approximately 13.2 million existing homes in California. Home performance retrofits are able to be successfully performed on nearly every home, and older homes can see many benefits from the Energy Docs Home Performance retrofits.

I heard you want to put “half-sized” air conditioners on homes in Redding- is that true? I have a 4 ton system on my house now- what size would give my home the Home Performance results I’m looking for?

When you realize what independent testing results across California have concluded- that the average installed system is only delivering 55% of its rated capacity in performance- it becomes easier to imagine a smaller system doing as good of a job as your existing one. For example, your 4 ton system installed by a local HVAC contractor, is delivering, on average, 2.2 tons of conditioned air to your home (4 tons x .55= 2.2 tons). When you also consider that an Energy Docs HP retrofit is going to reduce the air leakage rate on your home by 50%, install attic insulation that performs at full rated capacity, and design a high performance HVAC system- it’s easy to see how a new system can be aggressively downsized. We call this “right sized”- and right-sized systems deliver much more comfort and aggressive savings because they consume a fraction of the energy of previous units and run for longer times- enabling better mixing of the air in your home and proper moisture conditioning.

What is air sealing? Doesn’t my home need to “breathe?” Why would I want to spend money to air-seal my home, and then install mechanical fans to make it “leak” again?

Taking control of energy use starts with controlling the cost of conditioning the air that is in our home. Everyone knows that we need fresh air in our homes to stay healthy. Ideally, we would like to warm or cool the air in our home once, then keep that air inside for three hours. At that point, all of that air would be removed instantly, with brand new fresh air replacing it at the same temperature. Perfect. We paid to heat or cool it, and we used it all up. But wait, how do we instantly change our air, and what’s this about three hours? The smartest building scientists and engineers in the world, an association group called ASHRAE, determined that three hours is the perfect length of time for air to stay in our homes for the best compromise between indoor air quality and energy efficiency. And, since it isn’t possible to instantly change the air, we do it steadily over 3 hour intervals through mechanical ventilation and constant air exchange with the outdoors.

If we have a home that is full of many invisible leaks (as most are), outside air will move through the home very randomly. Some days, such as cold and windy days, will make our homes leak air at a very high rate- easily as high as one full volume of air every hour. Other days, such as mild, calm ones, will leave all of the air in place for many long hours. Stagnant air, full of contaminants, is what the indoor occupants are forced to breathe on these beautiful spring and fall days when our conditioning systems aren’t required to operate. Consequently, homes with many invisible holes and cracks have the highest energy use as well as the most random indoor air quality.

When we properly design and implement mechanical ventilation in conjunction with targeted air sealing, we reduce the effect of the changing outside environment on our stable interior environment. In doing so, we provide the highest quality of air with the lowest cost of system operation. Providing the right amount of fresh air to the proper locations, and removing pollutants at their sources, keeps the air within our home balanced and fresh, affordably.

What it is, what it’s not, and why

A home performance retrofit (HPR) project provides you, the homeowner, with better comfort, better indoor air quality and a safer, more durable home which uses less energy. After an ideal home performance retrofit, your monthly expenses are less—not more—than they were before the project, even after accounting for the added monthly cost of a loan which might be needed to fund the HPR project.

The building as a whole—your home working as an integrated system—is what provides better comfort, combustion safety and high-quality indoor air at much less energy cost than what your home used before the project. Savings of 40 to 60% are typical, even after adding ventilation air that it never had before. Those savings are usually enough to make the project self-funding. In other words, after the project is complete, your monthly expense is lower, even with the monthly cost of a loan to finance the project.

Self-funding projects

Full home performance retrofit projects are not small projects. To achieve monthly savings in heating and cooling costs large enough to make the project “self-funding,” a HPR project will typically cost between $10,000 and $60,000. It usually includes replacing the entire heating and cooling system, including new duct work. The new heating and cooling equipment will be less than half the size of the current equipment. The new air distribution system will be smaller, simpler and air-tight. The AC system refrigerant charge and the air flows will be measured and set. The project will seal the complex construction assembly which separates your home from the attic, so that conditioned air cannot escape upwards into that attic. Then at the end of the project, we will add insulation in the attic, burying the new sealed and insulated ducts so that heating or cooling capacity is no longer lost to the unconditioned attic. Home performance retrofit projects also usually include replacing the water heater, pumps for well water or pool filtration, and any lighting fixtures which penetrate the ceiling. Typical projects also upgrade the bathroom exhaust fans to near-silent units and provide a system which provides your home with filtered air for ventilation.

Those are the usual hardware components of a project. If this sounds like a big, complicated project—it is. But the most important difference between individual component replacements and a home performance retrofit is that all of the critical energy features are redesigned and reinstalled together, as an integrated system. The resulting home energy system is not only carefully engineered; it’s also measured in its critical aspects as it is being installed—by the installers themselves. Our installers’ final “test-out” reports are an absolutely essential part of our project. These provide certainty that your building envelope and the HVAC components will work as a highly comfortable and energy-efficient system, in sharp contrast to the historically disappointing results of the traditional piecemeal approach to building and remodeling houses.

Typical energy savings after home performance contracting projects are between 40% and 60% of the pre-project HVAC energy consumption. But just like driving a fuel efficient car, “your actual mileage may vary...” The dollar amount of savings will depend on how much energy your home used before the project. That’s why the first step in evaluating a house for an HPR project is to obtain and review the monthly gas and electric bills for at least a full year, and preferably two.

HPR projects are rarely only about saving energy. History has shown that for most homeowners, the non-energy benefits of better comfort and less noise, coupled with increased home resale value, are usually just as important (and sometimes even more important) than annual energy savings.

The Energy Docs, true home performance contractors, measure the installation quality and document it at every step. And unlike traditional HVAC system installers, for the HPR contractor, quality is never assumed- it is always measured. The cost to document results is not the issue. The act of measuring the quality during the process is what makes the installation excellent, instead of ineffective. Competition may be a useful device to avoid overpaying for any service—provided that all potential bidders are required to measure the quality of the home performance retrofit as it proceeds, and also required to provide the homeowner with documentation of those measurements.

The HPR approach sometimes seems less glamorous and uncomfortably complex compared to simply replacing your old AC equipment with a shiny new unit with an impressive-sounding seasonal energy efficiency ratios. HPR is more complex, and for good reason. To save significant amounts of energy demands modifications to many aspects of your home at the same time. The Energy Docs always delivers savings along with improved comfort and assured safety- all of which are important to you, the homeowner.

Why do I have to replace my high-SEER cooling unit just because it’s oversized? That unit’s nearly new! Isn’t it a good thing to have “spare” capacity?

You’d certainly think so. But unfortunately, oversized units create major problems for both comfort and energy cost. SEER stands for “Seasonal Energy Efficiency Ratio.” The rating number is based on tests under a carefully controlled set of conditions which do not reflect the realities of installation, or the variability of daily operation. Equipment which has too much capacity is like a suit which is too big for its owner. It doesn’t fit right, so it’s clumsy and uncomfortable. When cooling units are too big, they deliver intermittent blasts of large amounts of cold air. Then because they are so big, an oversized unit satisfies the thermostat quickly and turns off. As a result, for much of the day the occupants are either too warm or too cool. The larger the oversizing, the worse is the comfort. Also, the bigger the unit, the more energy it uses while creating that discomfort, and the more noise it makes in the process. To deliver energy efficiency and comfort in real homes (rather than in the carefully constrained SEER testing lab) the AC unit and all its system components must be sized and installed the way a fine tailor makes a suit—fitted perfectly to its purpose, and crafted with careful attention to the critical details which vary from house to house.

Why do I have to replace a perfectly good furnace with a heat pump, hydronic furnace, or 90+ efficiency rating just because it’s larger than the load? Aren’t you guys just running up the bill?

Oversized heating units generate the same discomfort and energy waste as do oversized cooling units, except that the symptoms of that failure are different. Instead of intermittent blasts of cold air, the furnace produces blasts of hot air. When the furnace is too big, it runs for very short periods, satisfying the thermostat quickly. Unless everything else about the house and the duct system is well-fitted and air-tight, the house is too cold (or much too hot) in the spaces where the thermostat is not located. With short run-times, the system can’t mix the air evenly throughout the home, providing discomfort in all spaces. So occupants without enough heating are complaining. They turn up the thermostat so the home uses more energy than it should. The oversized unit and the poor duct system combine to produce an inefficient system, even though the lab-tested efficiency rating on the furnace was impressive. So once again, like the man who gets sold a suit which is “the next size up,” a home with an oversized heating system is less comfortable, not more so. And oversized equipment costs more to run, no matter how high its lab-tested combustion efficiency might be. All in all, comfort and heating costs are not controlled by combustion efficiency. The cost of comfort is controlled by how efficiently the total system can maintain temperature in the occupied spaces. And furnace efficiency is only a small part of that process.

Can I get government or utility funding for an HPR project?

That’s quite possible. We are experts on all financing and rebates, and will share with you which programs might apply to your situation. Current available include our CHF Residential Loan program which provides very low interest rates (0 to 3% fixed for 15 year term) for qualifying applicants, and City of Redding rebates up to $9,000. for HP projects.

My kids have asthma. Will HPR improve indoor air quality?

Definitely. When outdoor air is filtered through the HVAC system rather than dragged through the walls or crawl space, the quality of the ventilation air is much improved. It will have fewer particles, and it will carry fewer of the allergens which can trigger asthma attacks. To be clear on this point, however, an HPR retrofit is not a cure for asthma, nor is it a guarantee that your loved ones won’t develop asthma. But an HPR retrofit will improve indoor air quality.

My spouse is sensitive to mold. Will HPR fix my mold problems?

If mold is a concern, the Energy Docs are well-qualified to eliminate the cause of mold growth, which is always some form of excess moisture accumulation. Once the problem is identified, the contaminated materials will be properly and safely removed, and the repairs necessary to avoid a repeat problem will be performed. If you want to know more about reducing mold risk and what it takes to accomplish that goal, consult the California Builder’s Guide to Reducing Mold Risk, which is available in PDF format at no cost at http://masongrant.com/pdf_2008/California_Builders_Guide.pdf

Why can’t I just seal the attic & duct work and add insulation to save energy? Why do I have to replace the entire HVAC system and the can lights that penetrate the attic? Aren’t you inflating the project?

Sealing the building and duct work and adding insulation would certainly save some energy. The key things to keep in mind are the safety and comfort issues. Safety first. It’s OK to add insulation to the attic—but only after the assembly that separates the attic from the living space has been air sealed, and after the lighting which penetrates that attic has been made safe. You don’t want moisture accumulating in your attic, and you don’t want the lighting fixtures to overheat and start a fire up there. And it’s OK to seal up the building, but after doing that, it’s critical to also check the safe operation of combustion appliances and make any necessary changes to ensure safety. You don’t want the water heater to “back-draft” (flames coming out of the unit and/or toxic carbon monoxide gas flooding backwards into the house). Provided you can also accommodate those safety measures in the budget, we can certainly just air seal the attic and duct work and add insulation.

Next up is comfort. After the loads are reduced by insulation and air sealing, then the existing AC and heating equipment is going to be really oversized. Some rooms will be way too hot and others way too cool. Resetting the air flows to the correct values probably won’t be possible because the system and its duct work is still problematic and is simply much too big. (It’s difficult to modify a bulldozer and turn it into a sports car) The home probably won’t be comfortable. For these reasons, air sealing and insulation are usually not proposed alone. By replacing the HVAC system with one which fits the new, reduced loads, comfort is assured and the total energy savings are more substantial—usually enough to actually lower your net monthly costs, even after paying the loan to fund the larger project.

Why do I have to mess with electrical system rework and lighting replacement before I put insulation in the attic?

It’s a matter of safety, code compliance and resale value. Here’s the safety issue: If either substandard wiring or old can lights are covered with insulation, they can overheat and start a fire. The additional insulation keeps the heat generated by the lights or poor wiring from being released into the attic air. On hot days, that heat under the insulation may be enough to ignite nearby combustible materials. Then there’s the matter of code compliance. It’s not OK to connect new equipment or new lighting fixtures to wiring which is defective or substandard.

Can Energy Docs also install a solar hot water or solar PV or wind energy?

Yes. A home performance retrofit project is an excellent time to add those features to the home. After the heating and cooling loads have been reduced, you won’t need as large a solar heater or Photovoltaic (PV) solar array. So you’ll save money on that side of the project. Like window replacement, the added costs of renewable energy generation are seldom paid back by energy cost savings in a short period. But as long as that’s not a problem for your budget, by all means install renewable energy features at the same time.


The Home Performance Process

Visit 1 - Test-In

The first visit to the site will take three to six hours in total. The Energy Docs will sit down with you during the first hour and interview you to gain a detailed understanding of all of your concerns and motivations for the project. After a room-by room tour of your home, we will inspect the crawl space and the attic, record nameplate data from the installed HVAC equipment & water heater and also inspect the lighting, wiring, electrical appliances, pumps and the main electrical service panel. Then our crew will test and measure key aspects of the building’s performance. This will include a blower door test of the air tightness of the home and duct systems, and a combustion analyzer to measure of the efficiency and safety of combustion appliances. Depending on the potential project, we may also test other aspects of your home’s performance, and take measurements and photographs to allow development of cost estimates for HVAC system rework or redesign, water heater replacement, remediation of electrical problems, etc. Upon leaving after three to six hours of interviewing, inspecting and testing, we now have the information needed to prepare a proposal which will save energy and meet your needs.

Develop the Proposal

Back at office, our project designer will prepare a preliminary proposal. The preliminary proposal will typically include a work scope, and an estimate of potential savings and overall costs. At this point the proposal will be general until the next meeting where it can be adjusted with you and subsequently developed into a more detailed project design.

The Second Meeting

At the second meeting, the Energy Docs designer will explain the proposal, roughly what it will cost, what it will save, what comfort benefits are expected and about how long it will take to complete. We will also explain how and why the test and inspection results have suggested the scope recommended in the proposal, and how your non-energy needs and concerns are addressed by it.

Final proposal

After a general agreement is obtained during the second site visit, we will prepare a final proposal with a firm cost, estimated annual savings, the specifics of what equipment and services will be provided and how long it will take to complete the project.

Acceptance & Project Plan

Upon presentation of the final proposal, together we will agree to then accept or adjust the scope and costs, and sign the contract. At that point, the Energy Docs will schedule the project, complete the final design and order the project equipment and materials.

Do the Work

Once the project begins, everything will be designed and installed correctly, as a system. And during installation, key results are measured to make certain that your energy-saving goals will be achieved. To achieve 40 to 60% energy savings, super-human technicians with impressive certifications are not necessary. All that’s required is the Energy Docs good crews, working with effective in-process inspection tools like blower doors, thermal cameras, duct blasters and fog generators. These tools provide our workers with the visual clues which help locate shortcomings and quantify success. And these are motivated employees who know with certainty, at the end of each day, that they’ve done an excellent job. And you, as the homeowner, benefit from that excellent job. The key to our success is not flawless quality, or rigid adherence to a government-approved protocol nor even post-process testing by experienced energy professionals- it’s the in-process test measurements which prompt our crews to correct any defects before the project is complete.

Attic and crawl space cleaning & sealing: “Put a lid on it!”

After any stored materials are relocated, the attic and crawl spaces are cleaned and prepared for energy-related work. In some cases, rodents have found a home in these spaces. They’ll be evicted, and the space will be cleaned of their leavings by our subcontractor who is licensed to deal with such issues. In the attic, the task is to seal up all the gaps, cracks and holes which allow air to flow upwards and escape out of the ceiling. Sealing the assembly which separates the house from the attic is like putting a lid on a pot. The conditioned air is retained inside, saving energy and making the house more comfortable (less drafty) during both the summer and winter.

With a leaky attic, during the winter any warm air escaping out through the attic drags in outdoor air behind it, pulling that cold air into your home and creating the uncomfortable drafts which lead to turning up the thermostat. In the summer, as hot air in the attic cools in contact with air conditioned surfaces, it “falls into” the occupied spaces through those same gaps, cracks and holes, pulling more hot air into the attic as it falls into the house. So for comfort and energy savings in both seasons, the base of the attic (ceiling of the home) must be sealed up, air-tight. The same goes for the crawl space, when there is one. Air entering and leaving the house through the crawl space is not what you want to be breathing. That air carries humidity, mold spores and objectionable particles upward into the home, unless the top of the crawl space is sealed up air tight, just like the attic. When the home has a crawl space, we will first make sure it’s dry by fixing any perimeter drainage problems. Then a layer of vapor retarder material is laid over the dirt in the crawl space to keep water vapor from drifting up and condensing on the cool, air conditioned surfaces at the top of the crawl space. Then we air-seal the top of the crawl space, just like what was accomplished in the attic. Any penetrations of that “pressure boundary,” such as drain pipes, electrical wiring or penetrations for HVAC ducts are sealed using an expanding bead of foam.

As the sealing operations proceed, our crew uses a blower door to test the air tight integrity of their work, usually about once an hour or more. It’s not necessary to make a hermetically-tight air seal. But using a blower door and thermal camera to locate the remaining leak points, we can easily reduce the original air infiltration rate by 50% or more, making a tremendous reduction in your home’s heating and cooling loads. It’s true that all of the components of the energy retrofit work together to achieve the comfort and energy cost reductions which are so impressive. However, air sealing of the assembly which separates the house from the attic, and sealing the top of the crawl space, are probably the most fundamental building blocks of that success. That’s why our crews will take care to measure progress during the process, using the blower door and thermal camera to find and seal the gaps, cracks and holes.

Correct wiring deficiencies and replace outdated lighting

Over time, the wiring in houses can become less than safe. This may be result of “informal” wiring efforts by a previous homeowner, or because the wiring is old enough that it cannot be safely covered by insulation. Loose connections and worn or rodent-chewed wire insulation are not what you want buried under thick layers of your attic insulation. With substandard or damaged wiring, heat can build up within the attic insulation and cause a fire. So for safety reasons, it’s quite important for the Energy Docs to correct the shortcomings in wiring and the electrical system before adding insulation or installing any new equipment.

Since these electrical problems are so common, we have found the perfect time to complete a lighting retrofit is at the same time as correcting potential electrical problems. A typical target of lighting retrofits is the “can lights” which are the recessed fixtures which penetrate the ceiling of the home. These penetrations must be sealed up properly to keep conditioned air from escaping upwards into the attic. And because the attic will be filled with much more insulation when we are done air sealing, the insulation will fully bury the entire light fixture. The Energy Docs will verify that the metal enclosure of these can lights is rated for full contact with insulation (FIC-rated) to avoid creating a fire hazard. We have found that homeowners prefer the safety and reliability of replacement of all older, non-FIC rated can lights rather than trying to make them work in modern, high performance homes. And typically, installing new air tight, FIC-rated fixtures is less than the cost of labor and materials to be sure existing fixtures are safe for insulation contact, air-tight and will tolerate the heat which accumulates in the fixture after it is made air-tight and covered with insulation.

When we replace the “can lights”, we always specify and install lighting which is balanced with efficiency, cost, and productivity gains. Before any bulbs are ordered, we will interview you for the way you use your home, and make lighting recommendations which address the important aspects of light such as color temperature, color rendering, and lumen output. These may be terms you have never heard before, and we will take the time to help you understand what type of rooms require or benefit from certain types of light. Did you know that a compact fluorescent light bulb is 80% efficient at making light, whereas an incandescent bulb is only 10% efficient at it? Somehow the standard incandescent bulbs are sold as “light bulbs”, but a more appropriate name would be what they are 90% efficient at doing- making heat. And since heat that is made from the direct conversion of electricity is the most expensive type, and because we live in a climate that requires a lot of air conditioning in the summer, we save money twice by changing out incandescent lights to ones that utilized more modern technology (CFL, LED, etc).

And, finally, a properly designed and installed lighting retrofit by the Energy Docs will yield the largest return on investment of nearly any other improvement you choose. Did you know that a CFL can return, in just 4 hours of operation, the same payback as what a solar PV installation takes a full year to produce? Knowing not only what the performance improvements will return, but also the order you should perform these improvements, is what makes the Energy Docs the Home Performance experts you can trust.

Install new HVAC system & water heater

While there are exceptions, most of our Home Performance Contracting projects will include replacement of the HVAC system and water heater, even if the existing equipment is relatively new. For you, the homeowner, this may be the most puzzling aspect of the project. Why should newer equipment be replaced? It seems like a business development plan for the contractor- rather than a real need. But there are good reasons why your existing equipment and duct systems will no longer be appropriate for your retrofitted home, and we only install equipment which functions properly.

Here are the typical components in the HVAC portion of the project, and the reasons and ways they are utilized.

Smaller HVAC equipment

After air-sealing and insulation work has been performed, the heating and cooling loads on your home will be less than half of the pre-project loads. Also, past local practice (industry accepted “rules of thumb”) in the HVAC trades have led to gross over-sizing of equipment. Prior to modern building science, most homeowners and HVAC contractors opted to install the “next larger” unit to cover installation uncertainties, and uncertainties about the appliances and loads that may appear in the home over time. But with Home Performance Contracting, the loads are substantially reduced, and there is no uncertainty about either the loads or the installation quality—both will be verified during installation. Leaving oversized equipment in place and expecting energy savings would be like hopping into a Boeing 747 to zip over for a few items at the local supermarket. It is certainly a powerful and impressive vehicle, and may even be an effective choice for large loads and long distances. But for short trips, a bag of groceries and a single passenger, it’s tough to keep a 747 from flying way past the local supermarket, and it uses an awful lot of energy to get there and back. Oversized HVAC equipment is similarly difficult to control. It quickly overshoots the target temperature, creating too hot or too cold conditions, in spite of its impressive capacity. And it uses a great deal of energy while creating that discomfort. So to achieve significant energy savings and much better comfort, the Energy Docs has found, through local experience and verification, that it is always necessary to downsize both the heating and cooling equipment.

Smaller supply duct work with more return air

To provide comfort as well as energy savings, the cooled or heated “supply” air must leave the duct system with a high-enough velocity to properly blend and mix the room air, eliminating the hot and cold spots which lead to your discomfort and increased energy use. At the same time, that necessary high velocity must not blow directly onto you, or it will make you and your loved ones quite uncomfortable. Also, when not installed properly, high velocity air generates an annoying amount of noise as it enters the room. To provide high velocity without noise, discomfort, or high energy consumption, the duct work will need to be smaller. It will also need properly selected diffusers for the new air flow without perceptible noise. Finally, the diffusers will need to be relocated and aimed in a direction which provides good room air mixing.

Next there’s the very important matter of “return” air. Imagine blowing air into a soda bottle. If you cover the bottle with your mouth, without allowing any air to escape as you blow, you won’t be able to get much air into the bottle. It runs into a “dead” end. The same problem occurs in most HVAC systems. There’s not enough open area to let the incoming air flow out of the space and back to the system—so the incoming air is restricted from entering the room in the first place. That’s often why oversized HVAC equipment still does not provide comfort—the air from the system can’t flow smoothly into and out of the spaces it’s supposed to heat and cool. The solution is to figure out how much air must return back to the system, and design and install fixtures that let the air flow out of each space and back to the “return” air inlets of the HVAC system.

Finally there’s the matter of duct insulation. To avoid wasting heating or cooling capacity as the ducts pass through unconditioned attic spaces, the heat transfer through the duct surface will be reduced to nearly zero. This will be accomplished by first insulating the duct to much higher standards than in the past, and then burying that well-insulated duct under additional new insulation in the attic.

Seal duct connections & measure system air tightness

Past “standard industry” practice has allowed loose and “taped” duct connections to waste between 25 and 60% of the system’s capacity because the air leaks out before it reaches the conditioned space. (That’s another reason why in the past, HVAC installers often selected oversized equipment.) In an Energy Docs Home Performance retrofit project, after your new duct work and new equipment is installed, we seal all of the connections and seams with mechanical fasteners and mastic (a durable, air-tight sealant recognized by code for its superior performance). As the duct connections are in the process of being fully sealed, our installation crew will temporarily seal all the system’s inlets and outlets and connect the system to a calibrated fan. This fan pressurizes the system and measures any outward air flow. While the fan keeps the system under positive pressure, the crew will keep locating and sealing any cracks, pin holes and seams in the ductwork and equipment itself until the device shows that your system’s air leakage is nearly zero. And we never use tape to provide the energy-saving seal on your new system because tape fails over time- just like many businesses that don’t believe in giving customers the quality job they are paying for.

Measure and set air flows to each space

It’s not enough to just set the system air flow and “call it good”. Everyone does that. What matters is exactly how much air flows through each of your rooms, and how accurately it meets the calculated seasonal loads. Too much “supply” air in one room will starve a different room of the airflow it needs to stay at a comfortable temperature. Every room has unique area and orientation, and therefore needs different amounts of supply air to provide proper comfort. Once we have installed your new system, we always measure the individual air flows to each room, and adjust our control dampers to make sure each room has the right amount of supply air it needs to keep you comfortable year-round.

Charge AC system & and measure cooling effectiveness and efficiency

In the past, the refrigerant circuit of most air conditioning systems was simply connected and the unit turned on. But having the right amount of refrigerant in the system is critical to achieving both comfort and energy cost reduction at the same time—instead of just one or the other, or neither. After we have installed, tested and balanced the airflow of your system, we then measure its actual performance. Given the variability of systems and their match to the home, in nearly all cases these will measurements indicate that refrigerant charge will need to be adjusted to provide proper performance. During our system commissioning process, we will accomplish this task, and then record the key performance indicators of system air flow, condenser subcooling and evaporator superheat. When these are appropriately matched through adjustments to the refrigerant charge, they provide the necessary certainty that the system will perform at peak efficiency as loads change. And the Energy Docs is the ONLY company that will document and give you a measured report of exactly what final efficiency level your new heating and/or cooling system is operating at- just like a “miles per gallon” sticker on a new car. And we say that you shouldn’t accept anything less- you should always demand to know how your contractor will have you spend your money for the next twenty years as you operate the system he installed.

So for all of these reasons and more, the Energy Docs attention to detail will give you the best overall system performance through the proper design and installation of your new duct and HVAC equipment system.