Energy Audit Basics For Your Home
In 2007, I did a major remodel on 2/3 of my rambling, 1960s ranch house. I replaced single-pane windows, added extra ceiling insulation, built an attached solar greenhouse and installed solar hot water. I also changed the floor plan for better air circulation and easier heating.
When the work was complete, I did an energy audit. When I was a real estate agent, I suggested to sellers to conduct an audit to understand their home’s energy usage and how it can be improved. By doing my own audit, I’d be able to back up my suggestions with personal experience and show clients the entire process.
What is an energy audit?
An energy audit:
• determines your energy use
• gives recommendations on making the home more energy efficient
• shows which improvements have a quicker return on investment (ROI)
You can do an audit yourself or your utility may do one for free or a discounted fee. You can also hire a professional energy rater, who will give you a thorough report.
The benefit of hiring an energy rater is that, once your home’s details are in the software, the information about upgrades is input, and you get new results and recommendations. It’s an ongoing process to upgrade and audit for the best efficiency.
Preparing for my energy audit
I chose to hire a professional, my friend, Alva Morrison who is a Certified Energy Rater. Alva knows energy efficiency. He has been in the weatherization industry for many years. Here is what he needed to start my audit:
• my gas and electric bills for a year
• an estimate of how much wood I burn
• age of the house
• volume of the house
• approximate wall area
• numbers and square footage of windows and doors
• type of construction
Once he had my data input into the software, we closed the windows and exterior doors, and left the interior doors open for airflow. He ran a blower door test. He installed a high-power fan in an air-tight panel in an exterior door and plugged it into his laptop. When he turned it on, air was moved out of the house, and we could find leaks of air coming in through cracks and other small openings. I was surprised to find air infiltration where I didn’t expect it!
My energy audit analysis
The report Alva prepared gave me new information about my house. Some I knew and expected, but some of the recommendations and ROI were a surprise.
My insulation is old and sagging, and I was prepared to open some walls and replace the insulation and sheetrock. The report said this was not cost-effective. It suggested I insulate around my foundation, two feet deep, 4’ thick for less airflow through the building envelope and a higher ROI.
It also said replacing the fairly new woodstove with a gas stove would have a greater ROI as well. I hadn’t considered this, either, but to me, burning wood, which is renewable, is more efficient than using fossil fuels.
The few old windows that were left should be replaced with low-e windows.
When I make these improvements, I will give the information to Alva to input into my file in his software. He will generate a new report each time I do this, and it becomes a living document. All in all, the house got a good report. I opted to get a HERS (Home Energy Rating System) score in addition to the audit. My house received an 88, which means it is 12% more efficient than the model home, which is the reference point of 100. Alva said this was great, considering the incomplete remodel and age of the home.
An energy audit as a selling strategy
An energy audit is a good tool for homeowners when they decide to sell. As you saw, it will show which improvements bring the highest and quickest ROI. It will also show potential buyers exactly how efficient the home is. Improvements can be done by the homeowner or negotiated with a buyer.
If there is no audit on a home, a buyer can pay to have one done. This way, s/he will know how efficient the home is as well as the cost of improvements to upgrade. Those costs can be rolled into an energy efficient mortgage (EEM), but that is another topic entirely.