I hadn’t noticed any absorption, but it’s not really that big of a concern for me as we’ll be roofing over the whole thing. The hollow core stuff needs closer centers, supposedly, but 12″ should be really solid. I largely left the details of spacing and such up to the contractor- we talked about it, and I agreed with his decisions, but I didn’t fuss around with it much. Like I say, though, the flex isn’t significant, but I noticed it. I guess I could fantasize that this is a form of earthquake proofing 🙂 The edging planks on ours are screwed down as well- since the clips require contact at both edges to work, there really isn’t much choice I guess?

Regardless, the deck and spa are a huge improvement over what we had. I’m happy with the composite decking so far, although the real measure of how happy I am will be a decade from now. If it is still in good shape, then it will have achieved what I wanted from it in this climate. The spa is sunk quite nicely into the deck: you can climb in pretty easily from any side.

I’m not perfectly happy with the way the lifter bar for the cover is situated, but the top mount type that would have worked well with our deck doesn’t work with the unusual shape of the cover we have. End result: there has to be a gap in the deck on that side to allow space for the lifter bar. One nice feature is the way we covered the service hatch for the spa: the contractor built a lift out step there, which given the mass of the composite board is rock solid. If we need access to the spa motors, the step lifts and can be shifted out of the way: nice and slick.