Mesh on pex in concrete question

[MScott]

I just finished laying out the pex for my garage floor and have stapled it down on top of the foam and placed the mesh on the pex. My question is whether I need to tie the mesh down to the pex is it ok just laying there.

 

[gatchel]

I just finished laying out the pex for my garage floor and have stapled it down on top of the foam and placed the mesh on the pex. My question is whether I need to tie the mesh down to the pex is it ok just laying there.

Typically the mesh is not at the bottom of the slab. Some people say the middle, some people say the bottom third of the pour.

 

[stingry]

I just finished laying out the pex for my garage floor and have stapled it down on top of the foam and placed the mesh on the pex. My question is whether I need to tie the mesh down to the pex is it ok just laying there.

It is fine just laying on top of the PEX. The weight of the concrete and the finishers walking on it will keep it in place.

Cheers
Steve

 

[MScott]

Typically the mesh is not at the bottom of the slab. Some people say the middle, some people say the bottom third of the pour.

The mesh will not actually be at the bottom of the slab (which would make it completely useless,) it will be on top of the pex which places it in the bottom third of the slab. I have searched this and the consensus seems to be that placing it on top of the pex is the best compromise. I considered suspending the mesh on stands, but I know that when the workers walk on it during the pour it just gets pushed down anyway and counting on them to lift it up is not likely to happen. I just have not seen anyone mention whether the mesh should be tied down or not.

 

[Highbeam]

It won't float up. So long as the concrete guys don't trip on it and lift it somehow screw up by blasting concrete under it, the mesh will stay down. Use the big flat sheets that lay nice and flat and tie them together at the edges to minimize the chance of the above accidents.

 

[MScott]

Thanks. I couldn't see any reason it would have to be tied down, but it isn't something that can be changed after the pour. I appreciate the thoughts.

 

[maxspeed96ct]

The mesh is fine on top of the tubing . I've heard debates before reguarding the mesh being in contact with the tubing causing issues if there's expansion and contraction, but working in the industry we always have done it this way and haven't had any issues. Personally I think the tubing movement is so minimal and the tubing is pretty rugged .

 

[rburke65]

Where would the tubing go?......it is encased in concrete! Or amI missing something?

 

[maxspeed96ct]

Where would the tubing go?......it is encased in concrete! Or amI missing something?

That's what I said , but some of these engineers fresh out of college just like to pretend they really know what they are doing ..

 

[jloram]

A couple of things to consider: If the PEX is under the mesh it's going to difficult to make repairs if the concrete guys rupture a tube. I tied my PEX to the re-bar in my six inch slab, pressurized the tubing and then stood by when the slab was poured to make fixes. (You'll know instantly if they bust a tube!) (see http://www.loram.org/Mt House Shop Construction.htm)

 

[powerhound]

Where would the tubing go?......it is encased in concrete! Or amI missing something?

I was told that the pex tends to "float" because of how it comes coiled. For that reason, I put mesh (suspended 1" off of the foam board) zip tyed my pex to the top of that and then put rebar on top of that so that when I saw cut my slab, I would have the rebar as a warning "barrier" if I got to close to the tubing.

 

[Highbeam]

The mesh can be cut in a flash with a cutting tool like snips or bolt cutters depending on gauge. Depending on your method of repair, you can easily work through the 6" grid.