Tying a House Together against the Wind

On September 22, 1938, after one of the worst hurricanes in American history, a newspaper reporter in Horseneck, Massachusetts, wrote of the “wasteland of sand and stone” that 48 hours earlier had been a town. He described “miles of summer places—from small cottages to large residences—smashed from their foundations.” The destruction of the resort area was all but total—yet, if only they had been properly reinforced or anchored, many of the summer homes there might have withstood the 100- to 130-mph winds of that terrible storm.

A cabin is most vulnerable to wind damage—and, in an area that's subject to high winds, should be reinforced—at the joints between the foundation, floor and wall, and at the joints between the wall and roof. Some of the reinforcing techniques that are described on the following be used as you build a frame structure; the other techniques can be used if you must strengthen an existing structure.

To reinforce the vulnerable points of a structure as you build, strengthen the joints with 1” 24-gauge galvanized- steel strapping, which is available at most hardware stores. The strapping comes with pre-punched holes for nails or bolts, and can be cut with a pair of metal shears. Check with local building officials before you install it: many codes permit strapping at every other stud or joist, but in some high-wind areas codes may re quire you to strap every joint.

Your local code may also require you to install diagonal reinforcements to protect stud walls against winds that can rack a wall out of square. Traditionally, these reinforcements have consisted of “let-in” bracing—1-by-4s or 1-by-6s recessed, or let in, to notches cut in the studs. Many codes now permit the use of metal braces, available from building suppliers, which serve the same function but are nailed directly to the studs, eliminating the tedious job of notching each stud by hand.

On existing structures, strapping can not be conveniently applied to exposed studs, joists or rafters, but there is a variety of steel connectors and plates, in stalled over the siding, that can be used to strengthen some vulnerable joints. Another method for keeping a roof on a cabin and a cabin on its foundation is, literally, to tie the structure to the ground with steel cables that are anchored to deadmen: 5-foot timbers buried permanently in the ground. As an emergency measure before a storm hits, you can also secure a roof with sandbags.

Regardless of how you reinforce your cabin in a high-wind area, always board up the windows when a bad storm threatens, leaving one or two windows slightly open on the lee side of the house to equalize the air pressure inside and out. During a hurricane the air outside the house is a low-pressure area, and higher air pressure indoors can burst doors and windows out of their frames.

1. Anchoring foundation, floor and walls. Slip 30” lengths of strapping between the foundation and the loosely bolted sills at every other stud location, pushing through just enough strap ping to fold over the inside edge of a sill. Tighten the sill bolts firmly and nail the strapping to the inner edge of the sill.

When you have installed framing for the floors and walls, nail each length of strapping to the outer faces of the sills, header joists, sole plates and the edges of the studs. If the sills are set slightly back on the foundation wall to allow space for sheathing flush with the wall, nail the, strapping over the sheathing.

2. Bracing the wall. From each upper corner of the framed wall, run a metal brace downward at a 45° angle from the top plate to the sole plate; nail the brace to the top plate and sole plate and to each stud that it crosses.

3. Strapping the roof to the wall. Shape 36” lengths of strapping over the top of every other rafter and over the edges of the top plates and studs below, and nail the strapping to all three members. Follow the same procedure to strengthen the trusses of a truss roof. If rafters or trusses end in an overhang, anchor them with steel-plate connectors.

Reinforcing an Existing Structure

88 Anchoring floors and walls. At the location of every other stud, set a 24” steel plate directly against flat siding, such as plywood, and nail it to the sill, header joist, sole plate and stud. In clapboard or other angled siding, cut through the siding to make a recess for the steel plate, so that the plate lies directly against the sheathing.

Linking a wall and a roof. Inside the house, remove sections of wall and ceiling covering to ex pose every other joint of a stud, top plate and rafter. Nail the end of a 24” length of strap ping to the face of each exposed rafter, twist the strapping to lie flat against the inside edge of the top plate, twist it again to lie flat against the side of the stud and nail it in place.

89 Temporary Ties to Anchor a Cabin

In areas of occasional high winds, you can quickly tie down an unreinforced cabin, employing steel cables and a method used by professional riggers. The only permanent installation is four deadmen—5-foot sections of telephone pole, buried 4 feet deep in trenches parallel to the roof ridge. Each deadman has a 12-foot ¼-inch cable looped and clamped around it and each cable has a turnbuckle on its free end. Where soil is loose or shifting, deadmen must be buried at least 6 feet deep, a job for professionals. If telephone poles are not available for dead men, you can use rail road ties or pressure-treated 8-by-8s.

You also need to keep ready two steel cables, each long enough to go over the roof from turnbuckle to turnbuckle. The ends of the dead man cables rest on the ground until the Weather Bureau issues a storm warning. Then you run the unattached cables over the roof and attach them to the turnbuckles on the dead- man cables. Old tires at the eaves and half-tires placed over the ridge protect the roof when you tighten the turn- buckles. Adjust the turnbuckles only enough to take up slack; too much tension can damage the ridge beam.