How can I anchor composite decking material to the top of an existing concrete deck?
I’m expanding the deck area with a wooden structure, and want the whole thing to be covered in the same stuff. A: TREX is my favourite composite deck material. It’s a 50/50 blend of reclaimed wood fibre and plastic, is solid in cross-section (as opposed to hollow, like some), looks good and machines well. A new wave of all-plastic deck lumber is hitting the market, and these are worth looking at, too. I’d begin by bolting two-by-four strips of composite material to the top of your concrete deck, spaced 24 inches on centre. (Double check maximum allowable support spacing for the composite you’re using.) Orient the support strips on their flat (not on edge), and use expanding masonry anchor bolts every 24 inches to fasten them to the concrete. Choose the size that fits into a half-inch diameter hole, extending two or three inches into the concrete. A rented rotary hammer makes quick work of boring these holes. Next, build your new deck frame so the top of the floor joists are level with
