Seal those gaps and drafts

Sealing windows: Your premium guide for success

Don’t let the heat and moisture in! Sealing windows is the easiest way to increase the energy efficiency of a drafty house and protect your home from damage and moisture issues. Get your window sealing tips here.

The essentials of window sealing

Sealing windows isn’t hard with a bit of basic knowledge. A waterproof sealant is very important in order to keep moisture and air from entering your home. It should be applied on all sides of a window and anywhere there is a gap that could allow weather in.

How to seal a window from the inside

You should seal the gap where the window meets the framing or trim and seal the trim prior to painting. Sometimes, you might use two different sealants - for example a completely waterproof sealant, like silicone, should be used against the window, but a paintable sealant is best on the trim (if it is to be painted). Just make sure all gaps and cracks are filled so that there is no air or moisture penetration from the outside.

The procedure is simple:

  1. Wipe down the area to be sealed so it is free of dust, grease, or anything that could inhibit adhesion.
  2. Insert a sealant tube into the gun, cut the dispenser end of the tube so that it will deliver the proper width bead of sealant. Pierce the foil seal inside the dispenser if equipped.
  3. Squeeze the trigger of the gun as you dispense the sealant evenly down the gap between the window and trim.
  4. Wipe the bead of sealant to smooth it out and seal the edges to the surrounding materials. Use a gloved finger, a damp rag, or a sealing tool.

Broken seals or old sealant should be removed as much as possible before applying new sealant as directed above. That’s really all there is to it. Clean up excess sealant right away and you’re ready to enjoy a better protected home.

Sealing window trim—exterior

Sealing the exterior of a window is much the same process. You’ll need to use a waterproof, exterior-grade sealant for this. The sealant should also hold up to UV light so that it doesn't degrade in the sunlight.

It’s best to wear gloves when working with sealants and adhesives, but if you get some silicone on your hands, try to remove it before it dries. Using an oil-based lubricant or even cooking oil on a rag will often work well. If you think a little grit would help, add a bit of baking soda to the oil. If the silicone has dried, try acetone (nail polish remover) or a commercial hand cleaner.

Choosing an excellent window sealant

Make sure the window sealant you choose is waterproof and anti-mould, since moisture is always an issue around windows. It should also stay somewhat flexible to maintain the bond to the window and frame as temperatures change and building materials expand or contract. This makes silicone sealant an excellent choice because it has all these qualities.

A great selection from an industry leader would be Loctite Clear Silicone Waterproof Sealant. This indoor/outdoor multipurpose adhesive is perfect for windows. It creates a protective, waterproof seal that will stick to metal, glass, rubber, wood, and vinyl—practically any material you’ll encounter around a window! It won’t crack, peel, or shrink, even in extreme weather.