Carefully interview contractors who want to do your job. Make sure that the contractor knows what's important to you and what kinds of problems you might already be aware of: comfort, health, safety, energy costs, sustainability/green. Be sure that the contractor has the understanding, experience, and tools to address these issues. Like any industry, there is a lot of snake oil out there. Fortunately, there are also top-shelf providers who can vastly improve your home.
It’s a bit like making the best use of your doctor, and taking an active role in your own healthcare. Many patients these days do their own research and take it to their doctor. They grill their doctor about their philosophy and strategies.
Following are some practical tips on get a good job done. We start with some overall questions that will help you figure out whether a given contractor is going to do good work for you that that they will actually improve your home’s energy performance, comfort, safety, etc. Some will glaze over when you go down the list, others will get a sparkle in their eye and jump right in.
The first list below is followed with more specific questions to help you ensure that the actual work is going to be done right. Go through these questions before signing a contract and again before paying the bill. Try to get the relevant issues included in your contract so that, in the unfortunate event they are done wrong, you will have a better chance to get them fixed under warranty.
Selecting a good contractor
- Do they listen actively when you describe your situation, and ask clarifying questions?
- Can they diagnose comfort problems you may have, or tell-tale issues like moisture damage or bad indoor air quality?
- Do they poo-poo energy efficiency and tell you it's not worth the effort?
- Is the contractor certified or accredited by a professional organization like BPI or RESNET that specializes in home performance?
- Find out if Home Performance with ENERGY STAR is available in your area. A qualified contractor inspects your home and recommends customized and cost-effective energy and comfort improvements.
- Can they persuasively describe some of the energy-saving strategies that they've used on recent jobs.
- If they are addressing an existing home (as opposed to new construction), will they perform a professional energy audit (including computer calculations to identify savings opportunities) before proposing work, or refer you to someone who will?
- How long will their assessment of your home take and what will it cost? A number around three or four hours is typical for a comprehensive audit and assessment. Prices vary considerably depending on thoroughness of the investigation and complexity of the home: for normal-sized homes expect a range of $300-$700.
- Describe the kinds of tests and measurements they do find out where the efficiency gains can be found and the kinds of tests and measurements they do after the work has been to determine that leaks have been successfully plugged and your home is safe. This process is sometimes referred to as "test-in, test-out."
- Are they aware of specific types of financial incentives (rebates, tax credits, etc.) available in your area? If not, will they find out for you and help you do the paperwork later?
- Will they evaluate your current energy bills and benchmark you against other homes?
- Do they test combustion devices like furnaces and water heaters for safe operation?
- Will they provide cash-flow or cost-benefit estimates to you for the improvements they recommend?
- Be sure to obtain user manuals and warranty documents for any equipment installed or services provided.
- Will the contractor provide a recommended maintenance program for things such as filter changes?
- Ask how the contractor locates air leaks in the home’s envelope (doors, windows, vents, etc.). The best practice is using a blower door.
- Ensure that the contractor runs blower door tests before and after sealing the leaks. Otherwise there is no way to know if progress was made.
Ducts (or boiler pipes)
- For existing or newly installed systems: Does the contractor measure the airflow from each supply register (or water flow for boiler piping) to ensure even distribution around the house?
For new construction or duct replacement: How does the bidder design duct systems? Look for an answer that indicates that custom calculations are done to determine the proper diameters of each duct run, minimize heat losses, etc.
- What insulation level do you propose for my ducts?
- What kind of sealing is used?
- How do you size the ducts?
- For existing systems: Do you pressure-test before and after repairs? If so, what percentage leakage do you typically attain once the job is finished?
- For new systems: Do you pressure-test the ducts you install? If so, what percentage leakage do you typically attain once the job is finished? Try to have ducts installed inside the conditioned space rather than attics or crawlspaces.
- Ensure that they minimize the length (“runs”) of the ducts, as the longer they are the more energy they lose.
- Be ware of supply grilles being located next to the (typically larger) returns. The problem here is that there can be a “short circuit” in which the conditioned air is captured before it benefits your living space, wasting energy and compromising comfort.
- Is the blower an energy-efficient model?
- Does the blower have variable-speed operation?
- Will all boiler pipe runs be insulated?
- Different windows are appropriate for different climates. Ordinary window stores and installers are often aware of the ideal window choice for their area. The consequence is excessive energy use, and compromised comfort.
- Ask the vendor for information on U-value and Solar Heat Gain Coefficient (SHGC). If they don’t know what these are, then they are not qualified to recommend the correct product.
- An energy-efficient window that is badly installed will create avoidable energy losses. Operable windows should have excellent air seals when closed.
- Ask for the efficiency of the unit they propose, and ask for the best efficiency available.
- Ensure that the contractor carefully insulates all hot water lines running from the heater, and even the first few feed of the cold line going in.
- Be sure the contractor does not leave the unit set on an excessively high temperature, which could create energy-wasting and scalding water for years. Many people are happy with a setpoint between 120 and 125 degrees Fahrenheit.
Heating and cooling equipment
- If replacing your furnace or air-conditioner, will the contractor go by the existing size or will the re-evaluate the situation to ensure that they are not oversizing (and that you are not over-spending)? Sizing should be done using a heating and cooling “load” calculation method, and not just guesstimated. If they’re proposing to replace as-is, you probably have an unskilled (or lazy) contractor on your hands.
- "When installing a boiler, be sure to adjust the factory temperature settings to be more attuned with your heating needs"
- When installing a boiler, be sure that not only the boiler itself but also the associated pumps are energy-efficient.
- "Do you install outdoor reset controls along with your boilers, or do I need to order that separately?"
- Do you measure refrigerant charge in the existing air-conditioner and correct if below the optimal level?
- What safety tests will you perform on the furnace? (Answers should include proper firing rates, exhaust air flow and carbon monoxide emissions).
- Ask the contractor what thermostat choices are available. They should describe the options in detail and be sure you know how to use any new thermostat installed. They should also test the thermostat in all modes of operation before leaving the jobsite.
- See the ACEEE list of tips for selecting a good contractor: http://www.aceee.org/consumer/how-choose-contractor
- Most leading residential contractors belong to the Air Conditioning Contractors of America (ACCA; see also their detailed checklist) or the Sheet Metal and Air Conditioning Contractors' National Association (SMANCA). Both sites provide listings of heating, cooling, ventilation and refrigeration contractors in your area. Look for contractors whose technicians are certified by North American Technician Excellence (NATE) and/or partnered with ENERGY STAR.
- Ask the contractor how they manage moisture so as to avoid mold or mildew, or degradation of the insulation over time Some good consumer resources are located here.
- Find out very specifically what type of insulation is being proposed. Newer approaches such as dense-packed fiber or spray-foam attain higher insulating levels, and better air and moisture control than traditional insulation.
- Quality of installation is key. Good insulation with poor coverage equals lots of unnecessary heat loss. Ask if contractor uses infrared cameras to verify thoroughness of installation?
- If your contractor proposes adding floor insulation over a crawl space, ask them to evaluate a “conditioned crawl space” instead. This is an approach where the walls around the crawl space are insulated and a moisture barrier is laid on the ground, and the space is heated as part of your living space. This saves energy, and if you have ducts in the crawl space, then their heat losses now occur inside the heated envelope rather than outside.