SUBSCRIBE to This Old House: http://bit.ly/SubscribeThisOldHouse.
With winter rolling in, plumbing and heating expert Richard Trethewey and home technology expert Ross Trethewey explain cost-effective ways to save money on heating to Kevin O’Connor. After presenting the tendencies and physics of heated air, Richard and Ross discuss the importance of insulating the roof of a home.
Heated Air is Predictable
Specific physics applies to heated air. First, it wants to move upward, often finding its way through the roof. Also, heated air will always move toward cold air, and the colder the air, the more it wants to move. For instance, if it’s 70 degrees in the home but only 15 degrees outside, heated air will work even harder to escape through the top of the building. It can also try to escape through the walls.
Insulate from the Top Down
Since warm air rises, you need to trap it in the home. Putting a warm hat on the building by insulating the attic is key. Fiberglass, rigid foam, and bubble pack insulation are great for the job. Just be sure that all the insulation is correctly in place, especially after any retrofit work might’ve occurred.
While many folks are satisfied with insulating between the floor joists in the attic, it’s not the best place. This is often where the heating and cooling mechanicals are, and leaving the attic space itself uninsulated makes it harder for them to work efficiently. Instead, consider insulating the roof itself.
Air Sealing is Just as Important as Insulation
There is a difference between insulating and air sealing, and when it comes to trapping heated air in, air sealing is critical. Issues like gaps between window panes, gaps under exterior doors, and even the space around an outlet in an exterior wall can allow cold air to penetrate the home while warm air pours out. A ¼-inch gap between window panes can equal as much as a hole the size of a baseball in an exterior wall. For ½-inch gaps under doors, that area can equal as much as a hole the size of a softball.
For leaky windows, installing new sash locks can help pull things tighter, but installing a shrink wrap kit around the window can help trap air and create a lot of insulation. Consider installing weather stripping around the side for doors with gaps and a door sweep at the bottom. For outlet or switch boxes in exterior walls, caulk around the gap between the box and the drywall to keep heated or cold air from passing through.
A Few Words of Caution
Many folks choose to shut heating zones off to save money during the winter. While this can be effective, pay attention to things that freeze within the space. Insulate any pipes in the unheated room or drain the pipes in completely unused areas to prevent freezing and splitting. Also, don’t forget to keep any radiators or heating vents clear from furniture to allow the mechanicals to heat the space efficiently.
Looking for more step by step guidance on how to complete projects around the house? Join This Old House Insider to stream over 1,000 episodes commercial-free: https://bit.ly/2GPiYbH
Plus, download our FREE app for full-episode streaming to your connected TV, phone or tablet: https://www.thisoldhouse.com/pages/streaming-app
About Ask This Old House TV:
From the makers of This Old House, America’s first and most trusted home improvement show, Ask This Old House answers the steady stream of home improvement questions asked by viewers across the United States. Covering topics from landscaping to electrical to HVAC and plumbing to painting and more. Ask This Old House features the experts from This Old House, including general contractor Tom Silva, plumbing and heating expert Richard Trethewey, landscape contractor Jenn Nawada, master carpenter Norm Abram, and host Kevin O’Connor. Ask This Old House helps you protect and preserve your greatest investment—your home.
Follow This Old House and Ask This Old House:
How to Save Money on Heating Bills | Ask This Old House