Deck ledger board failure - GIF

[hemmjo]

I count 12 layers of shingles in that stack. 3 bundles per layer. Typically 3 bundles per square(100 sq.ft.)except for some architectural shingles which are 4 bundles per square. Common weight is around 240lbs per square. I am guessing that stack contains 12 Square @ 240 per sq = 2880 lbs total weight. Stacked that close to the house, almost all of that is on the ledger board rather than distributed between the posts and the ledger.

Typical design standards specify 40lb per square foot as the minimum for EVENLY DISTRIBUTED live load. At 2880 pounds, spread over about 9 square feet, that stack represents 320lbs sq ft. Eight times the the design load for a common deck. Even assuming it was built properly to begin with.

I would never pile a stack of roof shingles on a deck, even if I knew it was built properly.