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rnhayden
Composite over Concrete

I have a concrete patio that is 16X16. I want to replace it with a composite deck. That is a lot of concrete to move and dispose of, is there a way I can cover the deck with the composite material (Trex, TimberTech etc)? I only have 2 inches to work with between the top of the concrete and the bottom of the door.

peterbouchard
Re: Composite over Concrete

Just throwing out some thoughts....

I would try to go over it for sure.

Nailing/adhering some 1x PT strapping to the concrete, then fastening the trex to that might work. You would want to do something to hide things from the sides of the cement patio. Frame it in.

I haven't used the clips, but maybe these clips would help in this situation. My concern is the 1x still doesn't give you a lot to bite to, but I think it would be fine.

Another thought is that you frame the patio with in some PT (anchored) and then just screw or nail the trex to the perimeter (full 16 ft boards). Not sure that would be good. YOu might get some slapping when walking on the deck...unless you put something down first to soften that. I'm not sure if you could use some splines to have the boards act as one (tongue and groove)..

Another idea is to tile the patio vs. going over it with trex. Tile might be brick, look like stone, or something along those lines.

Is there something wrong with the patio where you feel you need to cover it?

Any other ideas?

calcats
Re: Composite over Concrete

I'll repeat the question already asked, what is wrong with the patio that makes you want to cover it? If it is just showing signs of wear you might consider just a topcoat. If you have cracks and movement you will just compound the problem by trying to cover it because it won't stop the movement and cracking. Covering it with composite decking will be a waste of money if the latter exists, in which case I would tear it out and do it right. I'm afraid the only solution is yours do to the fact you are the only one who knows the conditions.

Calcats ;)

rnhayden
Re: Composite over Concrete

The current patio has pebbles in it so you cannot walk on it without shoes or some type of foot covering. We recently put in a hot tub and the rough surface makes it difficult to use the tub easily (yes we could use flip-flops etc but when company comes over it does not seem right). Also, out upper deck is Trex and trying to get the two to seem like one is another goal.

thanks for the help

calcats
Re: Composite over Concrete

The pebbles you see is called "exposed aggregate" and people pay extra to have that finish put on the concrete. How about some rubber runners to make pathways to walk on. Then you keep the aesthetics of the exposed aggregate but can walk without shoes and no slipping?

Calcats ;)

peterbouchard
Re: Composite over Concrete

Is there a sealer you might be able to use to soften up the edges somewhat and also give it a nice sheen?

calcats
Re: Composite over Concrete

You can buy a sealer but chances are it was sealed when it was poured. Plus, it might give a slight sheen to the stone but it won't make it any easier to walk on. If you don't like the rubber runner idea how about indoor/outdoor carpet runners? They look good, can be cleaned and thrown away when they get worn. Hope this helps.

Calcats ;)

peterbouchard
Re: Composite over Concrete

I never used a sealer. Sounds like the sealers are pretty thin then and even multiple coats wouldn't help.

calcats
Re: Composite over Concrete

You are correct, they are water-like and are designed to prevent a condition called "dusting" where the cement constantly seems as if it needs swept to get rid of the "dust". It also helps protect against erosion of the finish.

Calcats ;)

Re: Composite over Concrete
peterbouchard wrote:

Just throwing out some thoughts....

I would try to go over it for sure.

Nailing/adhering some 1x PT strapping to the concrete, then fastening the trex to that might work. You would want to do something to hide things from the sides of the cement patio. Frame it in.

I haven't used the clips, but maybe these clips would help in this situation. My concern is the 1x still doesn't give you a lot to bite to, but I think it would be fine.

Another thought is that you frame the patio with in some PT (anchored) and then just screw or nail the trex to the perimeter (full 16 ft boards). Not sure that would be good. YOu might get some slapping when walking on the deck...unless you put something down first to soften that. I'm not sure if you could use some splines to have the boards act as one (tongue and groove)..

Another idea is to tile the patio vs. going over it with trex. Tile might be brick, look like stone, or something along those lines.

Is there something wrong with the patio where you feel you need to cover it?

Any other ideas?

The best response here. Make life easier and just go over it. Also wrap the patio with pine or something to cover the patio edges.

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