Replies

1. 
   Matt | Dec 21, 2005 03:17pm | #1

   I guess you could do it but I bet the warranty would be void.   Trex will absorb water when installed too close to grade, etc.  Would you still be able to have equal height risers?

2. 
   VAVince | Dec 21, 2005 11:04pm | #2

   I saw Tom Silva do it on TOH. It looked great he attached right to the concrete with special expanding nails that you pre drill.

3. 
   davidmeiland | Dec 21, 2005 11:46pm | #3

   Trex has significant wood fiber content and I would not use it like that. It will rot, as far as everything I've read. I suppose for grins you could call their tech reps and see if this is a recommended application.

   There may be some composite decking that is entirely plastic, no wood. I'd look for something like that.

1. 
   VAVince | Dec 22, 2005 12:01am | #4

   The material Tom Silva used may have been plastic. I do not recall. I have seen that stuff used for a lot of things. One I really liked was a deck on a pontoon boat. Great idea but maybe a little heavy.

   Now that I think about it didn't FHB do a spread on the different brands and types a while back. That may have some useful info about direct contact with concrete.

   Edited 12/21/2005 4:09 pm ET by VAVince

4. 
   Mac_Built | Dec 22, 2005 02:19am | #5

   How about building out one step so each TREX tread is screwed to pt wood substructure that is screwed to the concrete? Your first concrete step down would become TREX at the same height as the deck, then drop steps after that. Your staircase will extend one step longer at the bottom. Do you have to build a handrail too or is that already in place?

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1. 
   Huck | Dec 26, 2005 06:15am | #11

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5. 
   DanH | Dec 22, 2005 03:52am | #6

   Keep in mind that anything you do will throw off the rise of the first and last steps. At the very least you need to use the thinnest material possible.

   If ignorance is bliss why aren't more people

   happy?

1. 
   reinvent | Dec 23, 2005 04:24am | #7

   The maroon who poured the cement steps made your concern irelivant, what I wan't to do can't make it any worse. I had thought of that though.

6. 
   EricGu | Dec 23, 2005 07:18am | #8

   My guess is that it will actually be less hassle to demo out the steps and build a proper set of wood/Trex steps.

7. 
   Renoun | Dec 24, 2005 11:09am | #9

   Somebody did this to my aunts patio in Seattle, a bit more moderate of a climate than Boston. As far as I can tell they used power actuated fastners directly into the concrete with some sort of small spacer/shim to allow drainage and air circulation below the Trex. I think it has been there around 5 years and there haven't been any problems so far.

   You will have variation in the rise of the steps which is a problem to consider.

8. 
   MGMaxwell | Dec 24, 2005 05:27pm | #10

   I don't think Trex absorbs enough water to be of any concern. It will outlast any wood you could use in that situation. If you want, you could route shallow grooves on the backside to permit drainage and promote drying.