Creating an airtight home
During the cold, dark days of winter, we often want a warm spot where we can curl up and relax at home. A cozy couch where we can sit with a warm drink and dive into your favorite book, watch the ballgame, or catch up on the news or social media.
But after a few minutes, something’s not right. One side of your body feels cold. So you shift your position, but soon the back of your neck has goosebumps or your feet are frozen. You can’t escape the chill. Is it a draft? A cold spot? An uncovered window? An uninsulated floor or wall?
In some homes, even those built recently, this can be a common experience. The cold finds a way in, often in mysterious ways. But how? And how can the cold be sealed out to make the home comfortable? As an energy assessor and building scientist, I’ve spent the better part of the last five years trying to answer these questions for hundreds of homeowners in the Yampa Valley.
It turns out the solutions to fixing drafty, leaky, cold homes are often simple. Some can easily be addressed as a DIY project: replace weatherstripping on doors, seal and insulate the attic hatch and by all means get out your caulk gun – because you’re going to need it! Other solutions are more complex and require tools to diagnose, and professionals to address.
The most common sources of drafts and air-leakage are from penetrations, gaps or cracks in what is known as the interior air-barrier, which is usually drywall or wood paneling. The air-barrier is supposed to be continuous, so any unsealed hole – an electrical outlet or switch, a light can in the ceiling, windows, ducts, wiring, plumbing, or structural beams to name a few – can leak air into or out of the building. In our climate, this often results in discomfort, heat loss, increased energy bills, and if you’re unlucky – ice dams.
However, to do this, one must find the holes first. Some leaks can be easy to spot if you know where to look, but finding those that are less obvious or hidden can be tricky and requires the right tools – a blower door, an infrared camera and a smoke generator. These tools help to confirm leakage in areas we expect, but also to discover leaks in areas we don’t – and we always find something unexpected. Using these tools also ensures we are finding and sealing the biggest leaks first.
Some leaks can be sealed from the interior with caulk and/or foam. Some require a more forceful approach, like the application of spray-foam insulation to entire assemblies, such as crawlspaces, rim joists or the underside of a floor or roof. Others, like tongue and groove ceilings without drywall behind them are nearly impossible to seal without a major remodel. When considering these and other costly improvements, it’s a good idea to get the help of professionals to prioritize which upgrades will maximize comfort and efficiency for the least cost.
Fortunately, as of 2019, new construction within Steamboat Springs has been required to meet a standard air-leakage rate. Most of Routt County is following suit in 2021. This has the benefit of decreasing drafts and air-leakage while improving energy efficiency, durability and occupant comfort. Some leading builders have prioritized building air-tight homes for years, and others are just catching on. It makes sense to ask about it when building or buying a home.
Indications that a home could benefit from air-sealing are high energy bills, persistent discomfort in winter and summer, a reliance on space heaters as temperatures drop and/or significant ice dams. If your home has these issues, do your best to address the common air-leaks listed above. If the issues persist, call in a pro to help diagnose and solve the problem, because winters here are too long to go without a cozy, comfortable spot to stay warm.
DIY air-sealing measures
Here’s a list of air-sealing measures that most homeowners can tackle.
- Seal the attic hatch with peel and stick weatherstripping. Also, insulate the attic hatch with rigid insulation to match the amount of insulation in the attic, R-50 = 10 inches of rigid insulation.
- Repair or replace weatherstrip on leaky doors.
- Install gaskets under the plate of any outlets and switches on the exterior wall.
- Caulk/seal baseboard trim to flooring, window and door trim and any gaps or cracks where drywall transitions to another material.
- Seal leaky light cans in ceilings with exterior penetrations (into an attic or cathedral ceiling) with integrated LED trim kits. Be sure to caulk the trim to the drywall when installing.
If the home is still drafty after these measures, it might be time to call in a professional.
Dan LeBlanc has been an energy efficiency and green building expert for more than 20 years on projects ranging from tiny homes to high-rise residential, and everything in between.