Sonicrafter F80 Oscillating Tool

Fast Fixes for Drafty Windows

By Joseph Truini

Don’t let cold, windblown air drive up your heating bills this winter. Now’s the time to take action and seal up drafty windows using a two-prong approach: First, caulk around the outside of the window, and then weather-strip the inside.

Begin by removing any old caulk or peeling paint from around the exterior of the window. You could use a stiff-blade putty knife or wire brush, but an oscillating multi-tool is much faster and easier. Use both the scraping blade and sanding pad. After scraping and sanding the surfaces smooth, clean away all dirt and dust with a dry scrub brush.

Oscillating Tool Sonicrafter F80
Use an oscillating multi-tool fitted with a sanding pad
to quickly remove dirt, grime and peeling paint.

Next, apply a fresh bed of caulk around the outside perimeter of the window, creating a continuous airtight seal between the window frame and siding or trim boards. And be sure to use an exterior-grade caulk, such as 100-percent silicone sealant, or “siliconized” acrylic caulk. Both types adhere well and will remain flexible for years.

Apply Caulking Sealant
Fill all gaps and cracks around the exterior of
windows with high-quality sealant.

After caulking the outside of the window, move inside and use weather-stripping to seal around the sash, which are the moveable parts of the window that open and close. There are many different kinds of weather-stripping available; here’s a detailed look at the top five types:

Adhesive-backed Foam

Adhesive-backed foam is a compression-type of weather-stripping, meaning that when the window closes against it, the foam compresses to seal gaps and block out drafts. It features easy peel-and-stick application, and cuts easily with scissors. Just be sure to thoroughly clean the area around the inside of the window; the adhesive won’t stick to dusty, dirty surfaces.

On double-hung windows, apply adhesive-backed foam weather-stripping to bottom edge of the lower sash, and to the top edge of the upper sash. If you don’t want to apply the weather-stripping directly to the sash, stick it to the sill below the lower sash, and to the head jamb above the upper sash. Either way, once the sash are locked closed, the foam will seal out drafts.

On sliding or casement windows, apply the adhesive-backed foam to the vertical edge of the sash or vertically along the side jamb.

TIP: Most double-hung windows have a single sash lock. However, adding a second lock will make the window much more energy efficient. Start by unscrewing the existing sash lock and reinstalling it one-third of the way from the side jamb. For example, if the window is 24 inches wide, move the sash lock in about 8 inches. Next, install a second sash lock 8 inches from the opposite side jamb. Now, when you engage both locks, the sash will form an airtight seal.

Tubular Rubber Gasket

Tubular rubber gasket weather-stripping is similar to adhesive-backed foam, except that it’s formed into a hollow rubber tube instead of dense foam. When compressed by the sash, the tubular weather-stripping conforms to the space, effectively sealing out the wind. Some tubular gaskets have peel-and-stick adhesive backing, while others have an attached metal or wood flange that must be secured with nails or screws. If nailing, don’t forget to bore pilot hole first or you’ll risk splitting the wood flange. Also, look for foam-filled tubular gaskets that have a spongy-foam core, which holds its shape better than hollow-core gaskets.

Spring V-Seal

Spring V-Seal is a resilient polypropylene plastic or metal strip that’s folded into a V-shape. It’s known as tension-seal weather-stripping because the V-shape springs open, creating tension—and blocking drafts—between the sash and window frame. Plastic V-seal can be cut with scissors, but you’ll need aviation snips to cut metal V-seal, which comes in copper, aluminum, bronze and stainless steel. Also, the plastic type often has a peel-and-stick backing, while metal V-seal must be nailed in place.

V-seal can be installed vertically along the sides of double-hung windows, and at the horizontal meeting rail where the two sashes meet when closed. On casement or sliding windows, V-seal is installed along the vertical side jamb where the sash closes.


Felt is one of the oldest types of weather-stripping. It’s commonly sold in rolls with or without an adhesive backing. And is also available with an attached metal mounting flange. Felt is used as a compression weather-stripping around the inside of double-hung, casement and sliding windows. Felt is affordable and easy to install, but it doesn’t last as long as other types of weather-stripping.

Window Insulation Kits

Window insulation kits block drafts by sealing the entire window behind a large sheet of shrink-wrap plastic. The plastic is adhered to the interior window casing with double-sided tape, and then shrunk drum tight with a blow dryer. Window insulation kits are very effective at sealing out drafts, but keep in mind that you won’t be able to open the window until spring when you peel off the plastic wrap.

So there you have it. With a little careful caulking and some perfectly placed weather-stripping, you’ll use less energy, save some money, and your home and family will be much more comfortable this winter.

Learn more about tools that can assist with similar tasks here

Category : How To, Uncategorized