What fastener to secure 5/4 decking directly to concrete
I'm installing a deck directly over a preexisting concrete patio. The concrete patio has a step right in front of the back door that is exactly the height of a 2x8 (7.25 in) if said 2x8 is used as a floor joist. Therefore, most of the decking will be going on the 2x8's however a 3'x3' area corresponding to the preexisting concrete patio back door step will have decking material lay directly on top of it. I am considering using the following to secure the decking to the surface of the preexsiting concrete patio step:
1.) 2 1/2" Tapcon screws (spray paint heads tan to match deck mate screws),
2.) 2 1/2" tapcon screws with USP Connectors CIA-EA Epoxy Anchoring Adhesive in hole to help hold Tapcon screw,
3.) deckmate mate screws with plastic concrete anchors, or
4.) deckmate mate screws with plastic concrete anchors AND USP Connectors CIA-EA Epoxy Anchoring Adhesive (this I'm not sure can be done since the epoxy might be incompatible with the plastic anchors... perhaps someone could chime in on this).
I'm particularly worried about the durability of any fastener option I chose since these boards will be walked on everyday, thus creating a challenge for any fastener to keep from working loose. What I'm wondering are two things: Besides the options I have listed, are there any other options that I haven't considered that would hold up better. Take in mind that large hex bolt heads would be unsightly if used for this application (even if recessed and spray painted tan), thus the reason for the only two screw options listed above with wood screw heads. Otherwise, if no other options exist, of those options listed, which would think would hold up the best. I'm partial for option 4 since I'm worried about even just one Tapcon screw head shearing off (which I've had happen before) which would be a bear to deal with.
Thanks in advance!
Last edited by howaboutthat; 11-12-2007 at 11:18 AM.