How do I stop a pergola from being blown over?
My husband built a pergola for our patio. But when the grape vines I planted for shade grew in, a strong wind blew it down. What should we do differently for the next one?
–Pat DiVesta, Roxbury, Conn.
Norm Abram replies: Grape vines or not, your structure needs to be extra strong in a location that gets a lot of wind. I'd build the next one like a timber frame, with mortise-and-tenon joinery and angle braces at the corners, and secure them with carriage bolts and exterior-grade construction adhesive. Everything else should be fastened with screws; nails can't be trusted for anything in windy areas.
Also, make sure the support posts are solid 6x6s, at least, and that they rest on concrete footings poured deep enough to stop frost heaving, probably 4 feet where you live. If you set the posts on the footing and fill and tamp around it all the way up to ground level, no wind could ever tip them over.