NJM Safety Center - Residential

Keep Wind and Water Out 

A Guide to High Wind Protection

The first step is to decide what level of protection you want and can afford — especially for doors and windows. Then you can permanently install any hardware that should be in place before storms start brewing. When a storm threatens, you can quickly install the protection and move on to other tasks and actions.

Protecting Windows

The highest level of protection normally available for windows is professionally produced shutters that meet the Dade County standards for opening protection. These standards require that the product be able to resist the impact of a 9-pound 2' x 4' traveling at 34 m.p.h. without penetration of the shutter, and if installed according to the manufacturer's recommendations, not break the glass behind the shutter.

This level of protection can also be achieved for small to medium sized windows by making the shutter of out a 1/4" polycarbonate sheet. This has the added benefit of providing a transparent shutter that will allow light in if the power goes out. The disadvantage is that the cost of polycarbonate material has continued to climb as oil prices have gone up. (A 4' x 8' sheet currently costs just under $200.) If you are making and installing your own shutters, you may want to consider this for your windows that allow the most daylight into living areas.

It takes about a 3/4" thick piece of plywood to provide close to the same protection as the Dade County approved products, and that will make for a very heavy shutter. You can of course use thinner plywood (and IBHS recommends plywood over oriented strand board, or OSB, because it takes 30% thicker OSB to equal the impact resistance of plywood.) Recognize that the resistance to penetration by windborne debris is reduced in direct proportion to the thickness of the plywood. In other words, a 3/8" thick plywood shutter would be only about half as effective in resisting penetration as a 3/4" plywood shutter. IBHS recommends 5/8" thick plywood as a minimum unless you are having problems with handling the weight of the shutter.

Some layer of plywood will always be better than not protecting your window, as long as it remains in place. And even the thinner sheets will help resist the most common wind borne debris such as small branches and shingles.

If you live in a community with tile roofs, IBHS strongly recommends you seriously consider Dade County approved shutter products for your windows. Our 2004 post-hurricane damage assessments noted considerable damage caused by wind-borne debris from roof tiles set with mortar.

Be Wise About Window Myths

  • Do NOT open windows during a storm. This only lets damaging wind and rain into your home.
  • Tape does NOT protect your windows from flying debris. It might keep more of the glass together when impacted, but it will not keep it in place.
  • Window film does NOT provide much gain in protection from impact of anticipated debris. Some thicker "structural" film has passed the small missile test, which applies to things like gravel or similar sized objects. It does help keep glass shards together when the window breaks.

Installing Plywood Shutters

If you are going to make and install your own shutters, take the time to pre-install the anchorage hardware and prepare your shutter materials now, before a storm threatens. Pick out and purchase the material you want to use and cut it to the appropriate size for the type of installation you select. There are a lot of effective ways to install shutters and many more that are not.

While you can nail plywood shutters as a last resort just before a storm strikes, repeatedly putting them up and taking them down will damage the area around your windows and doors, and ultimately affect anchorage quality.

Plywood is stronger in the direction parallel to the grain. So you can take advantage of the panel's inherent strength and place fasteners only on the sides perpendicular to the grain (for example, top and bottom as shown), or along the sides if the grain runs that way.

For installations on wood frame walls, you can order stainless steel studs that have wood threads on one end and machine threads on the other. Search under hanger bolts for the types of hardware you need. Select stainless steel anchor bolts for permanent masonry installations.