I was on an inspection Tuesday in Crestwood looking over a very nice home. The home had a nice wrap around porch/deck that went across the front and side of the home. On first glance all appeared well, however; the deck was not properly attached to the home. It has been an all to a familiar tale of a deck collapsing due to an increased load and improper supports. This deck has several issues, but the one causing the most concern is lag bolt spacing. A deck attached to a home is generally attached using a ledger board. It is this board that all of the joists are anchored to, and this is the board that holds the deck to the home.
The ledger board should have lag bolts installed every 16″ to 24″, or as determined by the length of the joists. Some of these were 36″ or more aprart. The longer the floor joist the closer the together the lag bolts should be placed. You can look up lag bolt spacing and see if your lag bolts supporting your deck are sufficient.
Another issue with this deck was the post holding the deck up were only supported by two nails in each at the top. Due to the height of this deck, the posts had already begun to bow significantly. The load factor and the attachment of the posts could lead to failure over time. Fortunately both of these are relatively easy fixes and once completed the home owner will have years of enjoyment out of this large inviting deck.