How to Inspect Windows, Doors to Stop Air and Water Leaks
Big picture inspection:
A home air pressure test , available from businesses like Eco-Analysts, Inc (207-386-0450) in Woolwich, Me, sucks air into the house to reveal air leaks that increase your energy bills.
- To inspect windows and other openings:
- Seal the house by locking all doors, windows, skylights, and shutting all vents.
- Close all dampers and vents.
- Turn on all kitchen and bath exhaust fans.
- Pass a burning incense stick along all openings–windows, doors, fireplaces, outlets–to pinpoint air rushing in from the outside.
Windows and the outside world:
Air and water can seep into closed widows from gaps and rot in frames, deteriorating caulking, cracked glass, and closures that don’t fully close.
- To stop air leaks, pinpoint window problems.
- Give a little shake. If they rattle, frames are not secure, so heat and air conditioning can leak out and rain can seep in. Some caulk and a few nails into surrounding framing will fix this.
- Look deep. If you can see the outside from around–not through–the window, you’ve got gaps. Stop air leaks by caulking and weather stripping around frames.
- Inspect window panes for cracks.
- Check locks. Make sure double-hung windows slide smoothly up and down. If not, run a knife around the frame and sash to loosen any dried paint. Tighten cranks on casement windows and check that top locks fully grab latches.
- Check doors for cracks that weaken their ability to stop air leaks and water seeps.
- Inspect weather stripping for peels and gaps.
- Make sure hinges are tight and doors fit securely in their thresholds.
- Inspect skylights
- Brown stains on walls under a skylight are telltale signs that water is invading and air is escaping. Cut a small hole in the stained drywall to check for wetness, which would indicate rot, or gaps in the skylight.
- To investigate skylight leaks, carefully climb on the roof and look for the following:
- Open seams between flashing or shingles.
- Shingle debris that allows water to collect on roofs.
- Failed and/or cracked cement patches put down the last time the skylight leaked.
How to Replace Weather Stripping
Identifying worn weather stripping:
Weather stripping deteriorates due to age, friction, and exposure to the elements. It also can be damaged by people, pets, and pests. At least once each year, inspect your windows and doors to check for air leaks that indicate your weather stripping isn’t doing its job.
- Self-adhesive foam tape loses its grip over time, causing it to pull away from the door or window frame — or fall off completely. Foam also can lose its resilience, no longer springing up to fill the gap.
- Rubber and vinyl weather stripping becomes dry, brittle, and cracked. Over time, it can also lose its shape and effectiveness.
- Spring-metal V-shaped weather stripping bends out of shape, cracks in spots, and comes loose thanks to missing nails.
How to remove old weather stripping:
- For peel-and-stick-type weather stripping, simply pull the foam strips off the door or window by hand. Stripping that is fastened in place with nails or screws requires a more tedious process of locating and removing all the fasteners
Options for new weather stripping:
- There’s no shortage of weather stripping options at hardware stores and home improvement centers. As is often the case, the cheaper and easier the product is to install, the less effective and durable it probably is over time.
- Adhesive-backed foam tape is inexpensive — costing less than a buck a foot — and peel-and-stick types are easy as pie to install. It works best where the bottom of a window sash closes against a sill, or a door closes against a door frame. It’s the compression that produces the seal. Don’t expect this product to survive longer than 3 to 5 years.
- V-shaped weather stripping, sometimes called tension-seal weather stripping, is the best option for the side channels of a double-hung window or a tight-fitting door. This product springs open to close gaps and plug leaky windows and doors.
- Inexpensive peel-and-stick V-shaped vinyl (as little as $0.50 per foot) is easy to install but won’t last much longer than foam tape. More expensive copper or bronze styles cost as much as $2 per foot and must be nailed into place, but they look better and will last decades.
- Tubular rubber or vinyl gaskets prove the most effective for sealing large and irregular gaps, such as around an old door. These hollow tubes are large enough to plug big gaps but soft enough to compress nearly flat. Types that are nailed in place last longer than peel-and-stick varieties. Prices range from less than $1 per foot for peel-and-stick to $1.25 per foot for nail-in-place.Prepare the surface:
- Before installing any new weather stripping, start with a smooth, clean, and dry surface. Remove all old adhesive using an adhesive cleaner and perhaps a light sanding. Fill and sand old nail holes. If old screw holes can’t be reused, fill and sand those as well.Installation tips:
- Some peel-and-stick types should only be applied when the temps are at least 50 degrees. Check the product label.
- Start with one small area to make sure the door or window opens and closes without difficulty before completing the entire job.
- Measure twice before cutting to prevent mistakes and waste.
- Cut rubber and vinyl varieties with shears or a utility knife, and metal types with tin snips. Be careful not to bend the thin metal while cutting it.
- Make sure to face the opening of V-shaped weather stripping out toward the elements to prevent moisture from getting inside.
- Adhesive-style weather stripping: Remove the backing and press firmly in place. Removing the backing as you go helps prevent the sticky part of the strip from accidentally adhering to something it shouldn’t.
- Nail-in weather stripping: Fasten the strips in place by nailing through the pre-punched holes. For double-hung windows, you’ll need to install the lower half, drop the sash, and then install the upper half.