Top Tips for Weatherproofing Your Garage Door

Making sure your garage door is appropriately sealed and insulated will also exclude water, dust, pests and drafts, making it more comfortable and energy efficient. If the door is not sealed properly it is easy for rain (or snow) to enter the garage, freeze, and damage. Warm weather can also attract bugs. Weatherproofing minimizes dirt, leaves, and even rodents from slipping in the bottom of the door. The following tips will help to seal up all the gaps, add insulation, maintain the weatherstripping, protect the metal parts, and keep your garage dry and warm all year long.

Inspect and Replace Weatherstripping

• Inspect current seals. Check the rubber or vinyl gasket (the door sweep) on the bottom of the door. If you can see light under the closed door, or feel airflow, the seal is worn and should be replaced. Similarly, check the vinyl doorstop weatherstrip on the frame's top and sides; it too should be free of damage and pliable.

• Replace worn seals. Remove the old weatherstripping if it is cracked or worn. For the bottom of the door, pull the old door sweep out of the metal track. Clean and lubricate the metal track (a bit of dish soap works well) so you can easily slide in the new rubber sweep. Find a cold weather sweep (often silicone) that maintains flexibility in low temperatures. When you have a wooden door, take out the nails that hold the old door sweep in place, apply a bead of caulk to the wood, then clamp and nail the new aluminum track before sliding in the new sweep.

• Install perimeter weatherstrip.First, take off the existing doorstop molding (often wood) and nail up the replacement, which is vinyl weatherstripping, along the top and sides of the frame. Cut it to size, and press it in a manner such that the angled flange is pressed against the door when the door is closed. Tack down the weatherstipping with nails, every couple of feet; then, momentarily, press the door against it and tighten the nails if gaps appear. When the weatherstrip is snugly pressed, hammer the nails fully in.

• SealPanel Gaps. If your door has sectional panels, you'll want to add weatherstrip between them. V-shaped strips or foam tape apply to the joints, these will compress as the panels move. That compressing helps close small gaps which allow wind chill to penetrate. (Gas charged insulated steel walls should interlock, but older wood panels may be installed with V-strip or foam tape at these joints, which helps even more).

By getting all the door seals fresh and tight, you are blocking most of the drafts, dust, and unwanted moisture at the door jam and floor.

Seal Gaps and Cracks Around the Door

• Caulk the frame. Caulk is good for filling gaps and cracks between the garage door frame and the wall. To ensure good adhesion, remove any old caulking first, and prime bare wood plans or concrete. Use a smooth finger or caulking gun to apply the caulking, keep it off the moving door surface. Press a foam backer rod into deep or wide joints (anything over about ¼ inch), then put a bead of caulk on top of that backer rod. This is especially useful along the top and side joints, to help seal section imbrication against wind and rain.

• Cover utility penetrations.Check for gaps where cables, pipes or switches pass into the garage next to the door. Any opening, even small, can let in cold air. Use thin foam gaskets behind wall plates on wall switches or seal around them with caulk. There are many small gaps where drafts can get in, so seal them up well.

• Use a door threshold. A rubber threshold strip secured to the garage floor can prevent water or wind getting blown under the door. Especially if there is a slope down toward the garage from the driveway, a threshold is a great benefit. Adhere the vinyl threshold with its glue strips so it actually forms a dam under the door. This way you kept rain, melted snow or new debris outside. A note of caution: thresholds can also trap water inside the garage too, so keep them clean and sloped slightly toward the garage door.

• Use a bottom door sweep. Adding, in addition to a threshold, a quality door sweep or bottom seal on your garage door if you haven’t already. A door sweep or bottom seal is the rubber or vinyl strip slides into a track at the bottom of the garage door. It compresses against the concrete, to seal out rain, dirt, cold air, and bugs. Rubber or vinyl can harden and crack over time, so replace it if it's flat or brittle; following the procedure above. For wintertime, replace it with a sweep made of silicone or another cold-rated material.

Sealing around the door and putting on a threshold will greatly minimize the amount of water leaks and air leaks.After a heavy rain or wind, check the floor by the door: Water pooling? Either adjust the threshold or caulk any newly discovered leaks.

Insulate the Garage Door

• Install insulation panels. Most garage doors (especially metal or vinyl doors that are single-layer) are very thermally conducive; adding an insulation kit can make a big difference. An insulation kit will typically consist of rigid foam panels that are cut to fit each section of the door. You simply measure the inside of each panel, cut your rigid polystyrene or polyurethane foam (usually found in two inch thick sheets), and then stick it in place with a foam-safe adhesive. Make sure to use an adhesive appropriate for foam board or expanded polystyrene; if an inadequate adhesive is used, it will melt the insulation. Or you can buy pre-cut insulation kits made specifically for the model of your door.

• Advantages of insulation. When insulated, the door will act as a thermal barrier that prevents cold air from entering into the garage and warm air from escaping from the garage. (One study found that an insulated door would keep the garage about 12°F warmer than an uninsulated door when outside temperatures were 20°F.) This benefits energy bills if your garage is heated, and stops cold air from entering the home if the garage is attached. Insulation will also help diffuse noise and can help to stop condensation from forming on the inside of the door.

• Think about a new door. If the door is dated or damaged, it may be worth selecting a new insulated door. The thermal performance of new insulated doors (filled with polystyrene or polyurethane foam) will outperform the thermal performance of adding insulation panels to an old door. Newer insulated doors have insulation built in during manufacturing, creating consistent insulation properties and seals.Most homeowners realize that a door with insulation is worth the investment because of energy savings and comfort.

When considering how to insulate your door, don't forget the windows in the door. If you can install a double pane window or insulated window kits, great! If not, consider covering the windows in clear plastic film to limit heat loss.

Maintain Hardware & Avoid Rust

• Clean regularly. Dirt, road salt, dirt, and pollen can cause moisture to get trapped against metal parts of a garage door and the paint, which can increase the chances of corrosion. At least twice a year, rinse the garage door and all hardware with a garden hose and wash the door with mild soapy water. Try not to use a pressure washer as it is possible to strip the paint. After cleaning, dry thoroughly including edges, tracks, and weather stripping. Make sure you wipe off all water.

• Touch up paint. Any chips and scratches in the door paint expose bare metal to moisture. When this happens, it is best to repair immediately with a metal primer and paint that matches. A good coat of paint is a good barrier from rust! If you are in a humid climate such as coastal, you could put a corrosion-resistant paint or a clear sealant over vulnerable places (like bottom panels where salt collects).

• Lubricate moving parts. When you apply oil or silicone spray to rollers, hinges, springs, and tracks you will limit the chances of binding and rust. Every few months use a garage door lubricant, or light machine oil, to clean parts.Silicone-based lubricants are especially effective at displacing moisture and preventing rust. This maintenance step minimises wear and prevents corrosion.

• Remove the rust that you already have. If you have any little rust spots, scrub them while they are small. If it is a light amount of rust, a vinegar-water solution and a soft brush is typically adequate; if there is heavier corrosion, use a mixture of water and baking soda, or use a fine wire brush. Clean the area, let it dry, and then put paint or primer back on. If left alone, rust can spread and eventually eat through the door panels or tracks.

• Use rust inhibitors. In coastal or highly humid conditions, you should treat the exposed metal hardware with a rust-inhibitor spray or oil. There are products on the market that produce an invisible film of protective coating that keeps moisture from making contact with the exposed metal. Furthermore, you should also keep your door's track painted or galvanized, and other exposed fasteners, like screws and bolts should also be painted or galvanized if possible, as they withstand rust longer. If you have a professional check-up, they will discover corrosion sooner and also re-tighten any fasteners that have loosened.

If you ensure that the garage door is clean, painted, and lubricated, and the mechanical moving parts remain in the same condition, it will reduce the chances of rust damaging the hardware and also stick the door in the close position when it gets really cold outside.

Final checks and seasonal maintenance After sealing and insulating, you should verify how effective your door will be at weatherproofing. On a day when it is windy outside, hold a candle or stick of toilet paper near the outer edges of the closed door, looking for air leaks. Any light or moving flame will indicate a draft - seal that area with additional weatherstrip, or caulk.

Quick checks on the bottom seal and outer weatherstrip on a change of season for cracks, replacing if needed, makes sure they don’t go unnoticed. Also be sure to clean debri and leaves from the track and threshold so that water cannot build up.

Lastly, if you ever see pooled water in your garage after it rains, trace it; you may have to re-seat your threshold, add an additional width of sweep, or re-calk all of the corners. If you want long term protection, you may want to seal the surface of your garage floor with an epoxy or concrete floor sealer to block moisture infiltration from below.

Key takeway: You should be able to conveniently seal every small gap (with sweeps, thresholds, and caulk), add insulation, and have clean metal parts that are lubricated. This locks out weather, helping to ensure your garage will remain dry and be maintained at a good temperature. With regular upkeep (seal checks every year, re-calk with new caulk, and refreshing paint and lubricants) your garage door will perform well in the heat, cold, and when faced with storms.