Straight Talk Articles

Those Drafty Old Windows: Alternatives to Replacement
June, 2017

Dear Pat: Our home is older than we are and the windows look like they are original. They let in cold drafts in winter and some of the rooms overheat in summer. We’re frustrated, but new windows are so expensive. Do you have any solutions? – Ken and Judy

Dear Ken and Judy:

 Yes, windows are an important contributor to the efficiency and comfort of your home. We talked about replacing windows  last month, but doing that is a big-ticket item and it could take twenty years of energy savings to recover that investment.  


Fortunately  you can make significant improvements without investing a huge amount of time or money. Let’s look at how we can address heat loss in winter and heat gain in summer at the same time.


We’ll start with the window itself.


Energy loss and draft often happen in the cracks between the components of the window. Weather-stripping can be used for areas where a window’s movable parts meet the window frame.  There are a variety of types of weather-stripping for different types of windows and parts of the window.  These materials are low-cost,  you can apply them yourself, and they can pay for themselves in energy savings in as little as one year.  Ask your local retailer for guidance.


The seam  between the window frame and the wall is another common source of air leakage. For anything less than ¼ inch wide, fill it with caulk; for anything larger, use expanding foam and paint over it, following the manufacturer’s instructions.


If the window pane is loose, or the glass is cracked or missing it’s probably costing you money.  If you’re handy, it is possible to re-glaze a window yourself, or there may be a shop in your area that will do it.   


Installing exterior or interior storm windows can sometimes produce as much savings as a full replacement.    It’s possible to order these windows  to the exact size of your window opening. Recent testing by a national laboratory showed that storm windows could cut heating costs by 7% to 12%.


Another strategy to consider is window coverings.  There are many types, including interior roller shades, cellular shades or draperies.  Recent laboratory tests showed that cellular shades could cut heating or cooling expense by 10 to 16%.  They can be purchased   

with a lighter reflective side and a darker heat-absorbing side that can be reversed with the seasons.


Draperies are usually less efficient but can also provide a level of comfort in winter and summer. For maximum effect, make sure they overlap in the middle, are as tight to the window and wall as possible, and run all the way to the floor.


A good solution specific to overheating problems is to keep the sun’s rays from reaching the window by installing awnings or overhangs above windows that receive a lot of direct sunlight.  Window films that adhere to the window surface can reflect unwanted summer sun.  Solar screens designed to block the summer sun can also be effective. 


If you’re on a really tight budget or there are windows to vacant rooms or the basement that you don’t need to be seeing out of, you can fasten plywood onto the frame on the outside of the house and cover the inside with rigid foam insulation.  Another very low cost measure for these areas that can produce as much savings as storm windows is to fashion a plastic weather barrier that adheres to the frame.  Building supply retailers sell a clear plastic and framing material that can be shrunk into place using a hair dryer.


Check with your electric co-op for rebates or incentives to help make your home more comfortable and energy efficient.

This column was co-written by Pat Keegan and Brad Thiessen of Collaborative Efficiency.


For more ideas on making your windows more energy efficient, visit the June 2017 More Information page.

Caulking seals air leaks around existing windows as well as new windows. Photo Credit: