Useful Deck Information

     The makers of Azek have developed a hidden fastener system that solves the problem most other products still have.  I’ve said before that I’m an opponent of hidden fastener systems for decks.  Up until now, I’ve never seen one able to create a stable deck structure like face driven fasteners provide.  Most are composed of brackets or guides fastened to the deck joists and fitted into grooves on the decking.  As the deck’s treated understructure dries out, it will push and pull, warp and twist in different directions.  Clips in grooves will not effectively hold the joists and rims in place.  Some others designs which are better, but still not great, are tongue and groove planks fastened through the tongue or groove.  This is stronger than the clip style.  But you’re still only getting one screw through the decking into the structure, and at an angle, versus two perpendicularly with traditional fastening methods.

     Azek’s revolutionary Cortex fastening system accomplishes both of the strength of face driven fasteners and the clean appearance of hidden fasteners.  The kit comes with a special bit which automatically sets the depth of the Cortex screw.  The Cortex screw has a specialized cutting head which bores a clean hole when driven through the decking surface.  Then a precut plug is tapped into the hole concealing the screw.  The plugs even have a matching wood grain pattern if you wish to line it up with the decking grain.  As an experienced Kansas City deck builder, I was very skeptical.  I just knew that with temperature and climate change, expansion and contraction, there’s no way the plugs would stay in place over time.  However, the salesman told me that Azek was confident enough in their system to stand directly behind it.  He assured me that Azek’s warranty even covers these plugs loosening or popping up.  The reason he explained for the plugs staying in place was that they are made from the same PVC material as the decking, and therefore, would expand and contract at the same rate.  I’ve seen and heard a lot of claims so I never believe anything until I try it for myself.

     So we sold our first Azek, about three dollars per square foot higher than Evergrain composite and still cheaper than some Timbertech lines.  My biggest fear was how long it would take to tap in a couple thousand tiny little plugs.  I was astonished at how smooth the process actually was.  The Azek plug system is nearly the same amount of labor if you figure how long it takes to pilot every screw hole and make sure all the heads are set flush when installing composite decking. 

     The Cortex conceal kit does cost a little more, about eighty to ninety dollars per hundred square foot.  From my experience, it’s well worth the extra dollar per square foot if hidden fasteners are a high priority.  If not, Fastenmaster has created a special line of Trap Ease colored screws that match Azek decking perfectly.    

Hope this helps,

Dan Milford (DW Elite Decks - Kansas City deck builder)

Azek "Brownstone"