How can I stop PVC decking from squeaking?

Question

We recently installed a TimberTech deck using all-PVC flooring. They use a clip fastening system (non-nail and non-screw)that recommends the floor joists be spaced for 12 inches on center, if diagonal. We built the structure on the diagonal but at 16 inches on center and fastened the floor boards.

We now experience a spring to the boards when we walk on them and a squeeking of the boards when we walk on the deck. The deck is 20 ft. by 35 feet.

We attempted to resolve the problem by placing 2x4 braces diagonally every 10 inches between each of the joists with the edge of the board nailed and glued to the joist and just "kissing" the floorboard so that the floorboard just rests on the support piece. This doesn't appear to be working -- less spring but still squeaking.

Any suggetsions? Desperate to find a solution.

Answer 1

Take up the flooring and install proper joists to be 8" on center.

At 12" on center your diagonal distance would have been just under 17". Now with 16" on center your diagonal distance is 22.6". That's way too long, and of course it's going to pull and squeak. I'd be worried about long term safety as well. Manufacturers do give recommended maximum spacings for a reason, after all...

Bracing it with 2x4"s which themselves are going to flex under the weight can't fix the problem. You need to properly reinforce the structure with properly sized joists.

Basically you went cheap on the foundation - now you're paying for it.