What You Need to Know About Home Energy Audits:
The U.S. Department of Energy does recommend that homeowners hire a professional home energy rating company to perform an energy audit of their home. The problem is that there are so many different green rating systems and companies out there to sort through that your not sure who to trust. For example, here are just a few:
BPI Building Performance Institute
RESNET Residential Energy Services Network
LEED-home U.S. Green Building Council
NGBS National Association of Home Builders
ENERGYSTAR Department of Energy
IECC International Energy Conservation Code
The list goes on and on with Green Seal, the Forest Steward Council, BREEAM, Greenlabel, etc… And to make things even harder, those are just the national green rating systems. Then you have other green rating programs at regional, state, and local levels, such as the new “Green Building Standards Code” recently adopted for the state of California. In Texas, we have the “Green Built Texas” program which is affiliated with the NAHB. In Austin, Texas they have the “Austin Energy Green Building (AEGB) Rating System.”
All these rating services have different formulas and levels of value for each category that is rated during an energy audit. The bottom line is that they are all working toward the same goal, which is to make your home more energy efficient. There are two main questions to ask when seeking an energy auditor:
How to Choose a Home Energy Audit company:
Question 1: Does your energy audit include a “Blower door” test?
Question 2: Are you a member of a “certified” energy rating service?
The top 2 energy rating services are BPI and RESNET. Both are excellent programs that require training, testing, and have quality assurance programs. With both these rating services you will receive a blower door test from a certified rating company.
A certified home energy audit usually last 4 to 6 hours and costs between $200- $500. The reason the cost may seem a little high is that it requires $4,000- $10,000 worth of equipment to do a proper certified audit. The main piece of testing equipment used is called a “Blower Door.”
During an energy audit, the “Blower Door” replaces your existing front door. It is attached to the doorframe while leaving your real front door wide open. There is an extremely powerful fan in the door that depressurizes your whole house by sucking all the air out. Then, the auditor will check all the walls, windows, doors, and ceilings throughout your home for drafts of air being pulled into your home by the extreme force of the fan. Often, smoke sticks may be used or incense for a more visual effect for the homeowner to see where the air is leaking into your home.
Another effective tool used by energy auditors is called a “Duct Blaster”. This tool is used to measure, test, and document the amount of air leaking from the ductwork of your heating and cooling system. It works under a vacuum type testing system as well. Air leaks in your ductwork can be costing you as much as 20 to 50% extra on your heating and cooling costs.
Another very expensive and efficient tool that is often used for energy audits is a “Thermal Imaging Camera”. Infrared cameras detect radiation and produce images of that radiation. Since radiation increases with temperature, the images reveal extreme heat gains and losses throughout your whole house. It can even detect missing insulation inside of walls. It is a very effective tool for finding air leaks.
During the audit, the Energy auditor will ask you a series of specific questions regarding your energy use history and your energy use patterns. The auditor will inspect all aspects of your home including attic insulation levels, attic vents, weather-stripping, caulk, closets, cabinets, doors, windows, etc... Following the audit, the auditor will combine that information with the detailed notes taken during the audit. Within a few days, you should receive a detailed summary of the analysis, as well as, an extensive list of recommendations and options for upgrading your home to be more energy efficient.