I bought 2 of these 7 years ago & again today. I live in the Pacific NW & they cover my chairs year round. They are on my top deck & not under trees. Mostly they worked great but in the last year the fabric on the top section just crumbled away. Verticals sides are all still in pretty good shape. I also have this cover on table & chairs set on lower deck that gets more shade. The fabric there did not crumble but in the last year as the fabric weakened the squirrels found it was easier to pull apart & began extracting pieces. All told, 7 years in rain & lots of wind ... worked great, no mildew, no wet.