How to Caulk Around Windows

Caulking can seal gaps between window frames and the window opening.

The windows of your home are one important component of overall energy efficiency. While many modern windows are built to prevent energy from passing through the glass and frames, if they aren't properly caulked after installation, energy loss can still occur. Applying a bead of caulking along the seams where the window is installed will reduce this energy loss and save you money on heating and cooling.

Things You'll Need

• Nylon bristle brush
• Sponge
• Caulking gun
• Utility knife
• Polyurethane caulking
• Popsicle sticks
• Rags

Instructions

1. Clean the area to be caulked. If you are caulking over an old installation, use your utility knife to scrape away old caulking. Use a nylon bristle brush to remove cobwebs or debris, then a damp sponge to take care of dust. Finally, wipe the area with a dry rag to ensure a clean, debris free surface.

2. Select an exterior grade caulking. Load the rube into your caulking gun. Then use your utility knife to slice the top 1/4 inch of the tube's nozzle off at about a 45 degree angle.

3. Start at the top of the window frame and run a bead of caulking along the seam where it joins the window opening. Hold the caulking gun at about a 45 degree angle and apply steady pressure to the trigger. Move relatively quickly, leaving a bead about 1/8-inch wide. Try to fill each seam with one continuous bead; avoid starts and stops whenever possible. Fill any seams or gaps you see, including small gaps along the window opening itself.

4. Smooth the bead with the end of a popsicle stick. Clean the stick with a rag when too much material builds up on it.

Tips & Warnings

• Specialized caulking spreaders are available. These inexpensive tools are sold in the paint section of most hardware or home improvement centers. On the other end of the spectrum, many builders simply use a finger to spread the caulking, If you choose the time-tested finger spreading method consider wearing a latex glove. Chemicals in caulking can be harmful.

• Some caulking is tintable, meaning the paint store can match it to the color of your existing house paint. This tinted caulking can create a seamless, classy finished appearance.

References

• Energy Savers: Caulking
• House Painting Info: Exterior Caulking Tips