If you live in an older, historic home, chances are your double hung windows have less than airtight window seals. You could spend the money to replace your older windows with new-style, energy-efficient windows, although many owners of historic homes may prefer to keep the original windows to preserve the historic nature of the home. The dilemma you are faced with is a how to create airtight window seals without replacing the windows themselves. With a simple router and a little elbow grease, you can eliminate the draft found on older double hung windows.
8 Easy Steps for Installing Airtight Window Seals
Remove the Window Sash Stop: Use a utility knife to score the paint where the inside stop meets the window frame. Using a putty knife, you can pry off the inside stop. Place a small pry bar adjacent to the putty knife and work the two tools together to free the stop. Be sure to remove any screws before you pry on the stop.
Remove the Lower Sash: With the stop removed you will be able to remove the lower sash. Raise the sash a few inches so you can place your hand under the bottom rail as you rotate the sash out of the frame. You will need to remove the cords or chains. Be careful not to let the cords fall down inside the weight pocket. The best way to avoid this is to tie a knot in the cord or in the case of chains, you can hook a clasp into the end link of the chain.
Remove the Parting Beads: Once again, use a utility knife to score the paint so the parting beads can be easily removed. Using wide jaw, sheet metal vise grips to prevent damage to the parting bead; clamp the pliers onto the parting bead and wiggle it out of the dado groove. It shouldn’t be necessary to remove the upper sash, as the new seals will be installed on the parting beads and the inside of the midrail of the lower sash.
Router a Groove in the Midrail: Use a router to cut a groove in the midrail on the inside of the midrail of the lower sash. The groove should be sized to accept the new seal which should fit snuggly into the groove.
Router a Groove in the Lower Rail: Use a router to cut a groove in the underside of the bottom rail of the lower sash. Again, the groove should be sized to accept the new seal which must fit snuggly into the groove.
Install the New Seals: Cut the new brush seals to length. To ensure you have airtight window seals, the brush seals should span the full width of the window sash.
Replace the Parting Bead Seals: Pry out the old parting bead seals being careful not to damage the wood. Clean out the grooves and install new bead seals. The new bead seals must span the full width of the window to ensure you have airtight window seals.
Reassemble the Window: Replace the parting beads, reinsert the lower sash and attach the cords or chains, and reinstall the lower sash stop. Repaint the window frame and enjoy your new airtight window seals.