There just wasn’t room for all of the things that can go bad with a deck in one article so here’s part two. Let’s see if we can squeeze the rest of it into this article, if not then part 3 may be forthcoming. Everyone has been to someone’s home for a BBQ and walked out onto a deck that seemed a little less than solid. I was at a cookout one summer evening and the fellow I was speaking with suddenly fell through the floor as if a trap door had been opened!! Fortunately for him it was only four feet to the ground so he sustained no injuries. Once he realized he was okay everyone including him laughed hysterically!! This fellow got off easy but these and other much worse scenarios happen every day due to neglected or ignored issues with decks. They can be quite serious if the deck is high off the ground, which is very common. So here are some more tips to make sure your deck isn’t a time bomb.
In part one I covered footings, support posts and deck/house attachment. Another very important thing to keep an eye on is how the floor joists are framed and attached to the front and back ledgers or bands, which are usually either 2×8 or 2×10. Many builder decks are framed in what is now a very outdated method. The joists meet the ledger board and sit on a 2×2 that is nailed across the width of the deck acting as the support point for the floor system(see photo). Some decks utilized the same 2×2 but the joists were notched out to sit on the 2×2. This method was known as bond timber and was also used quite a bit in home framing. The last method, and weakest is to just have the joist terminate into the ledger fastened with a couple nails on each side. This is referred to as a butt joint. What will happen over time is that the deck wood will move and shift as the weather changes. Treated pine lumber is yellow pine. Yellow pine is a fairly hard wood and as this hard wood dries from its treatment the grain will torque and twist the board out of shape, sometimes pulling joints apart.
The worst case scenario from this issue is when the front(outside) band twists so much that it will separate itself from the joists. As this front band is carrying the front half of the floor system load, which is quite a bit of weight, the joists can actually free themselves from sitting on the 2×2. This is not good and if the band continues to twist more joists will pull away and essentially be “floating” unsupported. You can easily check this out yourself, if the joists are not tight to that 2×10(picture a T) then you may have a problem. We just did a repair like this a couple months ago where the front band had twisted so badly that the joists in the middle of the span were a ½’’ off the 2×2 and the deck railing was leaning in toward the house about a foot because it was attached to the band. We had to build a temporary wall under the outside of the deck and replace the outer double 2×10 band. We refastened the joists to the new double band or beam with steel joist hangers. I will talk more about joist hangers in part 3.
To be continued……………..