An energy audit is a great way to create a plan to make your home more energy efficient, lower your utility bills, lower your carbon footprint, and help keep you more comfortable. An energy audit’s report can guide your energy renovations as you hire insulation contractors, allowing you to focus on the improvements that will have the greatest impact, save the most energy and money, and improve your home’s comfort the most.
An energy audit includes these primary components:
- A review of the past year’s utility bills to determine the baseline energy usage
- An interview with the homeowner to understand the problem spots and primary concerns
- An infrared scan of the exterior walls, ceilings, and floors to look for insulation problems
- A blower door test to measure the overall leakiness of the house to cold air and to find the worst leaks
- A thorough examination of the HVAC system to look for safety concerns as well as installation defects that contribute to comfort and efficiency problems
- A check for problems that can affect the indoor air quality
- A thorough report detailing the findings and providing recommendations for improvements, repairs, and replacements
Review of the past year’s utility bills
There are a couple of things in play here. First I just want to know where we’re starting from, so a record of the energy usage before making any improvements will help. Also I want to compare the current energy usage to standard energy usage throughout the area, to get at least a rough estimate on how the house is functioning currently, taking into account its age and its renovation history.
My energy audits start with a tour of the house. I want the homeowner to show me around so that they can point out any problem spots and areas of concern.
Infrared scanning of all the exterior walls, ceilings, and floors (if there’s unconditioned space below) helps to determine if there’s insulation present, if it’s installed properly or if there are gaps or voids, and it can give an approximate idea of how much insulation is present. These are all crucial factors in making recommendations for energy efficiency improvements.
Infrared image shows no insulation at the cathedral ceiling.
Blower door test
A blower door test is a standard test to determine how leaky the house is and where the worst leaks are. We all know that without insulation heat will more easily escape from the house. But cold air leaking in and warm air leaking out is also a big energy efficiency problem – a huge problem sometimes in older houses. Warm air rises in a house and wants to leak out up high in the house, while cold outside air wants to leak in down low in the house. Finding these leak points is essential to improving a house’s energy efficiency.
Blower door set up and ready for testing.
The way a boiler, furnace, or air conditioner is installed in the house can have a big impact on efficiency – and safety also. This is especially true of the ductwork (of course a boiler has pipes, not ductwork). So a thorough inspection of the HVAC system, its installation, and its design efficiency is part of an energy audit. One of the biggest problems with ductwork is that it’s leaky, and this is a problem that’s found as part of the blower door test.
There are many things that can affect the air quality of your house, but an energy audit is focused primarily on problems of ventilation. Poor ventilation can cause all sorts of problems with your house and can make your HVAC system work harder than it should. So now is the time to address these issues. Ventilation of bathrooms, attics, crawlspaces, and other areas are addressed during an energy audit.
Even the best energy audit is incomplete without a thorough report that guides you through the process of making upgrades and repairs to your house. A good report should be clear, comprehensive, and easy to understand.