Prevent Damage to Your Home from Windstorms and Hail
Updated: June 2015
In some areas of the country, wind gusts over 50 mph aren't uncommon. Add in the possibility of hailstones up to 1.5 inches in diameter and you need to be sure your house or rental property can withstand a pounding in the form of hail storms or windstorms.
Whether you're building a new house or doing periodic maintenance, upfront planning is key to your home's ability to dig in its heels against hail damage and windstorms. In particular, your roof, windows, and doors need to withstand the toughest weather that Mother Nature unleashes where you live.
Roofs: Strength from the Inside Out
During a windstorm, a primary goal is routing the wind's force from the roof down the walls, then to the ground. If your sheathing and gables aren't up to the challenge, your roof might end up in the neighbor's yard.
Sheathing is the wood, plywood, or wafer board nailed to the rafters or trusses of the roof. You can think of it as the part of your house your shingles rest upon. Some sheathing fails simply because nails haven't been properly affixed to rafters — during installation, the contractor may simply miss hitting the truss with the nail or may inadvertently use nails that are too short to "anchor" the sheathing.
You can get a good idea of how your sheathing's holding up by trekking up to the attic for a thorough visual inspection.
If your attic's prone to condensation, be sure to check for sheathing that's delaminating (plywood) or swollen (wafer board). Ask your contractor about secondary moisture barriers that can limit the delaminating and swelling that affect roof sheathing.
Take advantage of your contractor's expertise — find out what sheathing material offers the best wind protection in your area. Paying more now make may sense when weighed against the possible costs of windstorm damage later.
Gables are the side walls of the roof. If your gables aren't properly braced, strong winds can cause them to collapse. The most common method of bracing entails placing 2x4" wood pieces in an X pattern from the top center of the end gable to the bottom of the brace of the fourth truss and from the bottom center of the end gable to the peak of the roof.
Sheathing's an important component of a wind-resistant roof, but during hail storms, it's your home's shingles that may end up damaged. Impact-resistant asphalt shingles are a popular option against hail damage claims, owing to their ability to weather a hailstorm unharmed. Studies show that impact-resistant shingles can remain undamaged through 1.5-inch diameter hail, even though metal vents exposed to the same hail sustain large dents.
Windows and Doors: Precautions Help Keep Rain and Wind Out
Windows and doors can often be the most direct route for high winds to enter your house, causing severe damage to your walls and roof—and potentially ruining your family's personal possessions.
One of the most effective ways to protect windows — and keep you and your family safe from breaking and flying glass — is installing wind shutters (sometimes called hurricane shutters), protective coverings specifically designed to completely cover window and door glass openings during high winds. While some homeowners build their own wind shutters (typically using 5/8"-thick exterior grade plywood), information about custom-built options is widely available online.
Another option is purchasing pressure- or impact-rated windows. Besides protecting your home's interior from water and wind damage, they also increase its overall structural stability, reducing the risk of destructive structural failure from hurricane winds.
For doors in high-wind areas, at least one double door should be secured with heavy-duty bolts both at the top of the frame and at the floor. Be aware, though, that the bolts included with most doors aren't strong enough to withstand high winds. Check with a hardware store for heavier-duty bolts. The door's manufacturer may also sell a reinforcing bolt kit specifically made for your door. The manufacturer may also make pressure- or impact-rated doors that are designed to offer increased wind protection.
Doors installed to open outwards reduce the chance of the door blowing open in high wind. Inward rushing wind can cause pressure changes in your house, changes that can actually cause wall and roof structural failures.
Taking Action When Wildfire Threatens
If you are warned that a wildfire is threatening your area, listen to your battery-operated radio for reports and evacuation information. Follow the instructions of local officials. Remember, personal safety should always come first!
Back your car into the garage or park it in an open space facing the direction of escape. Shut doors and roll up windows. Leave the key in the ignition. Close garage windows and doors, but leave them unlocked. Disconnect automatic garage door openers.
Confine pets to one room. Make plans to care for your pets in case you must evacuate. Arrange temporary housing at a friend's or relative's home outside the threatened area.
Know at least two exit routes from your neighborhood in case of emergency evacuation.
Wear protective clothing; sturdy shoes, cotton or woolen clothing, long pants, a long-sleeved shirt, gloves and a handkerchief to protect your face. Take your emergency supplies kit.
Tell someone when you are leaving and where you are going. Choose a route away from fire hazards. Watch for changes in the speed and direction of fire and smoke.
If you're sure you have time, take steps to protect your home.
Close windows, vents, doors, Venetian blinds or non-combustible window coverings and heavy drapes. Lock your door and always remember if you are advised to evacuate, do so immediately.
Assembling Emergency Supplies
When wildfire threatens, you won't have time to shop or search for supplies. Assemble a disaster supply kit with items you may need if advised to evacuate. Store these supplies in sturdy, easy-to-carry containers such as backpacks, duffel bags or trash containers.
Include in the kit:
- A three-day supply of water (one gallon per person per day).
- Food that won't spoil
- One change of clothing and footwear per person
- A first aid kit that includes your family's prescription medications.
- Emergency tools, including battery-powered radio, flashlight and plenty of batteries
- An extra set of car keys and a credit card, cash or traveler's checks
- Sanitation supplies
- Special items for infant, elderly or disabled family members
- An extra pair of eyeglasses
- Important family documents stored in a waterproof container
Special thanks to the California Department of Forestry and Federal Emergency Management Association (FEMA) for contributions in the development of this material.