How to Keep Cold Air from Coming Through Windows

Older windows, even some newer windows, can let cold air right into your home. It happens because of cracks, failed seals, and poor insulation. If you’re trying to fix this problem by putting bubble wrap on windows, you can do better. Read on for how to keep cold air from coming through windows.

Adding bubble wrap or saran wrap to your windows does help insulate them, but not very well. And these fixes look sloppy, especially when they have to be done over each year, leaving adhesive marks or chipped paint.

What bubble wrap can’t do, is create dead air space between it and your window. That’s a big reason why double-pane windows insulate better than single-pane, the space between the panes. When trying to keep cold from coming through your windows, you want to add layers – of material AND air.

The way your house feels depends on the make-up of your house: wall and attic insulation, double or single-pane windows. All of these have an R value and a U value that together make the mean radiant room temperature. 

R value measures heat resistance and U value measures heat transference. A low U value (transfer of heat) and high R value (resistance to heat transfer) is ideal for high surface temperature. Together, these give us the combined effectiveness of the materials in insulating a room and our perceived temperature.

Mean radiant room temperature expresses the influence of all surface temperatures on comfort. That’s why someone sitting next to a window can be cold while someone across the room is fine. No matter what the thermostat says, if your windows aren’t insulated, you will have a low perceived temperature and comfort level.

Give up the bubble wrap. To really keep cold air from coming through your windows and increase the perceived temperature, you need to increase insulation. You can add another layer of insulating material and air with window inserts.

Indow window inserts are made with acrylic, which insulates better than glass. They use compression tubing to create a seal around the window frame. This adds an air pocket between the insert and the window for more insulation. Because the insert is on the inside of the house, it raises the surface temperature. 

Just one insert can have a huge impact on the mean radiant room temperature. Start with the coldest window and see what a difference it makes.