Do air leaks really cost me money?
A recent home that we tested showed a mediocre ACH50 number of 7.1. For a 1965 rancher with no updates, this isn't a bad result; it's not a great one either as new home construction in Maryland requires 3ACH50 or less. But for the existing building, it's not as bad as some of the others we've tested with similar construction.
The ACH50 number is nice to know in a general sense how many times your home exchanges air in a standardized test setting. It stands for Air Changes per Hour @ 50 Pascals. It doesn't tell you, though, what that costs you. Two separate homes with the same ACH number can have dramatically different infiltration costs, while two homes with different ACH numbers could have the same infiltration costs. While the ACH number is good to know, knowing what that means to you in your home is even better. These infiltration costs are derived based on the additional data of your climate information, home volume in cubic feet, and HVAC equipment type and efficiency.
Back to the home, the customer heats their home with an older oil fired boiler and has a central air conditioning system for the summer. The oil-fired boiler was old and could benefit from a replacement to a higher efficiency version as it is original to the home. The air conditioning system was updated back in 2015. The customer explained that the home's oil costs seemed relatively high when they talked to other neighbors and co-workers with oil heat. Now, this home has plaster walls with brick veneer, insulating the walls would be quite an undertaking for the customer from a DIY scale or a write large check to a contractor to spray foam in between each stud in all the walls. The customer thought that was the only option until the blower test showed something that created a faster payback and would enable the customer to decide later to insulate the walls if they wanted to later down the road.
After a blower door test and a walk through it was starting to make sense to the customer; during the blower door test, we also calculated infiltration costs. By using climate information and home information, it was found that $438 was spent on reheating infiltrating cold air into the home. At the price of $3/gal, that is almost 150 gallons of fuel oil, 3360lbs of CO2 emissions, wasted to reheat air that got cold not from the walls, windows, or ceiling insulation, but from the air leaks in the home itself. The majority of the air leaks we found came from door and window seals, attic access seals, and wood paneling walls that were never sealed. A much easier avenue for the customer to begin saving on their heating bill was to start tackling the small leaks and using that saved money that was already set aside to pay bills, to reinvest it into the home.
This customer saved money and reduced their direct carbon emissions from their oil burner by correcting air leaks in their home. Is this something you'd like SIY to consult you and your home about? Feel free to drop an email to info@siy.biz or fill out the form in our Contact Us section and schedule a consultation with blower door test. We will provide you with the information and guidance to tackle your project in a cost-effective manner for both your wallet and your energy savings.
