Rebar, not mesh, in basement slab
We are wrestling with the heating plan for a small spec house we’ll start this spring. At issue is whether to heat the ICF walkout basement space with in-slab radiant, or heat rooms with steel panel radiators.
But that’s neither here nor there. We think that we will reinforce the slab with rebar and not mesh. Using chairs, #3 bar, and 18″ centers, we might end up looking like what you see in the attached pic.
I think mesh is OK in slabs, but its effectiveness in mitigating cracking relies heavily on the pour guys doing a really good job of hooking it up so it’s not just laying at the bottom. After all, if it is just laying down low, you wasted money and labor to put it in.
What have you been doing for your slab work?
Replies
Gene,
Not sure this is relevant for you but the last heated slab I worked on the specs called for mesh then the heating tubing then 3/8 bar at 16" o.c.
Mesh was simply to tie the tubing to , it never was intended for reinforcement. One nice thing about this is that the bar helps protect the tubing from being cut when the slab gets "soft cut" after the pour.
The way dovetail described is the way we have been doing it. We use a 6x6 mesh. then #4 bar, but I think #3 would be adequate.The bad news is you've done exactly the right things to be exactly where you are today. "IdahoDon 1/31/07"
Gene,
The company that I work for does quite a few daylight basement homes. On non-radiant floors, we use #4 bar 24" oc. Radiant floors get 6 x 6 mesh for the tubing installers to tie to. Our radiant contractors will not use the "staples" into the rigid foam to hold the tubing. If the Client will pay, and the archi agrees, we'll use the bar with the mesh wired to it.
Harry
I use wire unless the substrate is in question at which time I use both wire and rod. You are right though, I have to keep telling the concrete guy what that "prong" is for on the back of their come-alongs... BTW - If you put rod in there, you may likely have to go with a slab thicker than 4".
BTW - I understand that up there they call it re-rod - which will get a snicker down here... :-)
PS - I've never done radient floor heating. It is very rare around here...