If you've ever installed new HVAC equipment, you've probably had your contractor perform a load calculation. You might hear your contractor refer to these estimates as a "Manual J" calculation, and they'll often use specialized software to perform them. While a Manual J can help you size your new HVAC equipment, it doesn't tell you everything about your home's energy needs.

If you want more information, that's where a whole-home energy audit can come into play. This service goes beyond a simple load calculation and can let you take a holistic approach to reduce your home's energy needs. These audits can also be helpful even if you aren't in the market for new HVAC equipment, so they're something worth considering at any time.

What Happens During an Energy Audit?

A whole-home energy audit covers numerous aspects of your home's energy usage, including your appliances, HVAC equipment, and heat loss through doors, windows, and wall insulation. While an energy audit will likely turn up many inefficiencies, the goal is to locate areas where you can perform high-impact improvements to reduce energy usage and utility costs.

Energy audits include some basic steps that you can even perform yourself. These tasks include checking the energy ratings on appliances, finding always-on electronics, or looking for bulbs that you can replace with high-efficiency LEDs. However, these relatively simple checks are only the first steps in a complete energy audit.

Auditors will also investigate your home's shell or envelope. This step involves sealing your house and creating a negative pressure environment, which allows the auditor to look for areas where unconditioned air can enter your home. Your inspector will also use specialized equipment such as infrared cameras to check for energy losses through uninsulated or poorly insulated walls.

Do You Need an Energy Audit If You've Already Performed a Load Calculation?

Most HVAC contractors perform load calculations when installing equipment, so will an energy audit save you money? The simple answer is "yes." A load calculation needs to account for potential energy losses, but it's a less thorough process that can't identify them all. More importantly, the goal of an audit isn't to address these issues but to size your HVAC equipment to account for them.

Performing an audit will allow you to identify problems with your home's energy usage. You can use this information to determine which issues provide the best bang for your buck to address. By fixing these problems, you'll help keep your home more comfortable while improving the efficiency of your existing heating and cooling system.

Ultimately, a home energy audit is a proactive approach to making your home more energy-efficient and reducing your utility costs. These inspections can benefit nearly all homeowners, even those with relatively new and well-sized HVAC equipment.