There is nothing better than standing by your window looking at a winter storm raging outside and feeling warm and snug in your comfortable home... except when your windows are leaky and drafty and when you stand or sit next to them you feel cold drafts in winter or hot moist air in summer.
Why Are Windows Drafty and Cold in Winter?
Cold air finds its way through small and large gaps and cracks in the window frame and window surround and infiltrates directly into your warm space.
Even double or triple-paned glass windows insulate less well than the average wall…so the interior surface of your window tends to be cold, and heat from your body radiates towards that cold area.
The colder interior glass surface of the window cools down the air in your room adjacent to the window, and as a result that body of air tends to fall to the ground and create a draft.
Top 3 reasons to seal leaky windows:
- You will be more comfortable in your home no matter what the season!
- You can save money on your heating and cooling bills
- There are a lot of steps you can take which are highly cost effective – including simple fixes which any homeowner can take on themselves or find a friend or local handyman who can help
The Economics of Window Sealing
We’ve all seen the ads for replacement windows, which say you can save 40% or even 50% of your heating costs if you buy new windows--Guaranteed.
But take care: the small print says you will save 50% of the heating losses you are currently experiencing through your windows – not 50% of your total heating costs. Typical homes with older single pane windows lose about 10% of their heat through the windows: so there is money to be saved, but it takes a long, long time for new windows to pay for themselves in energy saving.
However, sealing leaky windows using one of the techniques outlined below can be highly cost effective.
6 Options for Window Sealing
There are many different approaches to reducing leaks and loss of heated or cooled air around windows. Here are some of our favorites, running from the cheapest to the more expensive:
- Caulking gaps and cracks in the window frame and surround
- Applying plastic film to the interior of the window with double sided tape
- Installing interior window treatments: blinds and curtains
- Installing exterior or interior storm windows
- Removing the window framing to upgrade insulation around the window
Which Option or Options Are Right for YOU?
Here are 3 ways to figure out how to improve your windows:
1. Do your own diagnosis:
- Make sure the basics are good: take out window air conditioning units for the winter and systematically make sure all the windows are closed and locked and, if you have storm windows, make sure they are also down and locked.
- Use an incense stick or just a wet finger and move it around the window frame on a cold windy day to find out where the leaks are: identify where there are gaps you can caulk and get to work.
- Check whether your windows are single-pane or double pane: if they are single pane, and there are no storm windows, you need to take action to increase the low insulation effectiveness of single pane glass: plastic film at a minimum, storm windows and window treatments, if you can afford it.
- If your windows open, check whether there is weather stripping or an integrated design to minimize air movement between the window and the window frame; if not, check out our guide to weather stripping and get to work or get a friend to help out. Unless you live in a house of glass, this is an easy weekend project.
2. Get Advice:
- Find a local home energy efficiency club and see if they can recommend a local expert on windows who can take a look and give you advice; there may be someone who is prepared to help you at no cost because they are so committed to helping people save energy.
- Don’t get advice from a salesman for a window company! Their agenda is to sell you windows, not to tell you how to make your current windows more efficient. Besides, we can guarantee that you’ll be horrified at the cost—that is, assuming you can get an estimate from the salesman.
3. Take a Picture and Let Us Take a Look:
- Submit your pictures and our window expert, Dan, will take a look and tell you what he thinks! Use the upload form on the left hand side of this page.
Caulking Gaps and Cracks in the Window Frame and Surround
One of the best methods for sealing your windows against chilly winter drafts is to apply silicone or latex caulking, which can be purchased at most home improvement stores or right here at 360Chestnut. Place a tube of caulk in a caulking gun, run a bead of caulking wherever you detect a gap that is allowing air to flow and smooth the caulking with a wet rag, your finger or a smoothing tool. This option is inexpensive; quality caulking can last for several years and generally pays for itself in energy saving within one year.
More on Caulking
Applying Plastic Film to the Interior of the Window with Double Sided Tape
3M and others manufacture inexpensive window insulation kits. You use double-sided tape to position a sheet of plastic film to the inside of your window and then shrink the plastic and eliminate any wrinkles with the hot air from a regular hair dryer. This has the advantage of being one of the least expensive and simplest options, but it can be visible on the indoor frame of your window and will only last for one season, or until you choose to open your windows again. Even if it only lasts one season, you will more than make back your money!
Weather Stripping the Window
Most modern windows have overlapping strips and connectors to automatically seal gaps between sections of the window and between the window sections and the frame. For older windows there are many types of weather stripping that you can apply which will reduce leaks substantially. The process to install weather stripping depends on the type of product you choose, but most weather stripping can be easily applied by pressing pre-measured, adhesive strips against the inner and outer sashes of clean, dry windows. Like caulking, high quality weather stripping can last for many years.
See more on weather stripping options here.
And watch this "how to" video:
You can also submit a picture of your window to our experts for advice on which weather stripping option to pursue: use the form on the left side of this page.
Installing interior window treatments: blinds and curtains
Curtains and blinds are the old-fashioned way to cut down drafts and warm up a room. And today there are high performance insulated shutters and shades that really make a difference. For instance there are Hunter Douglas shades, which qualify for the recent federal energy efficiency tax break.
Installing Exterior or Interior Storm Windows
If you are able to spend a little more on your project to increase energy efficiency in your home, you may want to install storm windows. The cost is higher than the other fixes we have discussed so far, but if you install a quality storm window on an existing single pane window, you can expect to get your money back in energy savings in 4 to 6 years. Storm windows are available for most types of windows and they can be installed on the interior or the exterior.
Submit a picture of your window (or windows, if you have more than one type) to our experts for advice on which type of storm window is right for you: use the form on the left side of this page to upload your photos!
Removing the Window Framing to Upgrade Insulation around the Window
The performance of your windows depends not just on the quality of the windows themselves, but also on how well they were installed. In particular, if your installer did not really understand the importance of insulation or had not been fully trained in how to ensure that the areas around the window are well-insulated, then you may have windows where there are highways for cold air to travel and find cracks and gaps to enter your home. A qualified local energy enthusiast or professional with access to a thermal camera can use it to examine your windows and diagnose if this is an issue you need to address.