Sliding doors allow light and outdoor views into your home, but are also notorious for letting out heat and inviting cold drafts to slip in. This unwanted airflow can wreak havoc on energy bills and leave your family reaching for extra clothing layers on cold winter days. Weatherproof your sliding doors using weatherstripping and a few other tools to maximize indoor comfort and keep utility bills in check.
Start With Weatherstripping
Remove the active (moveable) door by turning the roller assembly screws with a screwdriver to retract the rollers. To remove some doors, you must unscrew a strip of stop molding along the top of the door; with others, you can lift the door panel upward, then pivot the bottom end out of the door track. Note: Glass doors can be very heavy, so have at least one helper for this step, and hold the door at all times if you've removed any stops. Place the door on sawhorses, a table or other flat surface.
Examine the edges of the door. Loosen staples holding weatherstripping in place along the edges of the door with a flat screwdriver. Pull the weatherstripping out by hand and use a putty knife to gently scrape away any remaining adhesive.
Install new brush or fin weatherstripping on the appropriate edges of the fixed and active doors. Position the strips so that the flaps interlock where the two doors meet. Use screws or adhesive to secure the weatherstripping to the edges of the door per the manufacturer's instructions.
Use a flat screwdriver to push weatherstripping out of the groove in the base of the active door. Replace it with new brush or fin weatherstripping by sliding the material into the groove.
Reinstall the active door and stop molding, as applicable. Adjust the roller heights so the door is securely in position, moves freely and is parallel to the latch-side door jamb.
Other Weatherproofing Strategies
Slip a length of rubber, vinyl or foam weatherstripping into the channel where each door hits the door jamb. Make sure the door still closes tightly, and use a smaller diameter material if needed to ensure the door will close correctly.
Caulk around the door casing on both sides of the door opening. Caulk any gaps between the bottom of the threshold and the floor to keep air from flowing under the threshold.
Install a sliding door insulation kit. These kits come with sheets of plastic designed to fit to sliding doors, using special tape. Use a hairdryer to complete the installation and remove wrinkles according to the instructions in the kit. Do not use insulation sheeting on doors that are required for emergency egress, such as main outdoor-entry doors in bedrooms and walkout basements.