Looking for imput on in floor heating???

[Paul-ish]

I just got my permit for my 30x30 Garage. Guys will be coming to dig up my yard next week. I am required by the city code to have 5 inches of gravel and at least a 4' pad with 16'x16' thick ends on all four walls.

Something like this pic.


Is there a way to do the infloor heating right in the original foundation???Or do I have to do my pad, then insulate it and do the rebar/wire mesh/ pex and then do another layer of concrete?

 

[motorcycle79]

Um I think that is all one concrete pour. U do all dirt work put foam down and staple tube to foam then mesh or rebar. That the way we do it in northern wi anyway

 

[Nowater]

I think mc 79 is correct. The warm floors might be nice in a garage. My Mom had hot water heat in the floor of her house and it was not comfortable, but a garage is different, in that I suspect you will not be keeping it as warm as a house.

 

[Paul-ish]

Well I've been making good use of the search function.

From what I've been reading I'll need to do my gravel / then a thick vapor barrier / then at least 2 inch thick foam insulation under and on the outside. Then put some supports for the wire mesh and re-bar so it's off the foam, lay all that out and connect the pex tubbing to the mesh.

Well I think i'm on the right track anyway...I'll keep reading.

 

[motorcycle79]

I would staple pex to foam way faster then to mesh but I wouldn't use mesh I would put bar in. Sounds like u are in the right track tho

 

[Paul-ish]

I would staple pex to foam way faster then to mesh but I wouldn't use mesh I would put bar in. Sounds like u are in the right track tho

Yeah that seems to be a fairly common way of doing it but I also read it heats much more efficiently if the pex is in the middle of the concrete instead of the bottom. I'm still trying to figure it out though.

Also i'm planning on using bar and mesh...So far anyway.

 

[911mike]

Level the gravel bases then lay down 2" of 250 psi foam. Tuck tape all seams then use mesh and wire all the mesh together. Zip tie the pex to the mesh. They make plastic triangles that lift the mesh off of the foam 2". It is better to get the tubing centered in your slab.

Keep in mind a lot of your cracking happens from temp changes. Now that your heating the slab you may only see 40-80 temps so cracking is way less. I have a 44 x 80 slab with heat and do not have a single crack in 4 years.

 

[StupidSheet]

Level the gravel bases then lay down 2" of 250 psi foam. Tuck tape all seams then use mesh and wire all the mesh together. Zip tie the pex to the mesh. They make plastic triangles that lift the mesh off of the foam 2". It is better to get the tubing centered in your slab.

Keep in mind a lot of your cracking happens from temp changes. Now that your heating the slab you may only see 40-80 temps so cracking is way less. I have a 44 x 80 slab with heat and do not have a single crack in 4 years.

Did you put in any expansion joints?

 

[911mike]

Did you put in any expansion joints?

Yes but just 2. I broke up the 80 ft into 3 zones. The saw cuts run between the zones the 44 ft long direction. One zone is walled off into a work shop.