mnRemodeler
Member
I'm building a shower. I had to remove sections of sub-floor to add the roughed in plumbing.
The original sub-floor had 3/4" OSB with a 1/2" OSB on top of it. Glued and Screwed. Sitting on over-sized TJ trusses.
I added another 1/2 layer of OSB over the above sub-floor in the area of the shower. So my shower has 1 3/4 inches of OSB. Plenty rigid. Also, adding that extra 1/2 inch gave me a solid sheet of OSB that spanned all the joints on the bottom layers of OSB that were there after the rough-in plumbing.
I then put down tar paper and floated a pre-pan using floormix made for that purpose and at a 1" depth at the perimeter and a 1/4" depth at the drain. That gave me a 1/4" per foot slope to the drain.
After doing the above, I'm now seeing videos where they recommended putting down wire mesh over the tar paper before floating the pre-pan. I didn't use any mesh because the tile shop's video, which I was using as a guide, didn't suggest wire mesh.
But based on my experiencing doing concrete floors, I know that mesh laying flat on the ground doesn't do anything. This would be the case of the shower pan since no mortar would be under the mesh.
So my question is...how critical is this wire mesh? I assume it helps prevent cracking, but again, without it being embedded in the mortar I'm skeptical that it would provide any value at all.
I'm not inclined to rip it out and add the mesh. I'm just curios how many people use the mesh and if anyone has seen a problem not using the mesh.
The original sub-floor had 3/4" OSB with a 1/2" OSB on top of it. Glued and Screwed. Sitting on over-sized TJ trusses.
I added another 1/2 layer of OSB over the above sub-floor in the area of the shower. So my shower has 1 3/4 inches of OSB. Plenty rigid. Also, adding that extra 1/2 inch gave me a solid sheet of OSB that spanned all the joints on the bottom layers of OSB that were there after the rough-in plumbing.
I then put down tar paper and floated a pre-pan using floormix made for that purpose and at a 1" depth at the perimeter and a 1/4" depth at the drain. That gave me a 1/4" per foot slope to the drain.
After doing the above, I'm now seeing videos where they recommended putting down wire mesh over the tar paper before floating the pre-pan. I didn't use any mesh because the tile shop's video, which I was using as a guide, didn't suggest wire mesh.
But based on my experiencing doing concrete floors, I know that mesh laying flat on the ground doesn't do anything. This would be the case of the shower pan since no mortar would be under the mesh.
So my question is...how critical is this wire mesh? I assume it helps prevent cracking, but again, without it being embedded in the mortar I'm skeptical that it would provide any value at all.
I'm not inclined to rip it out and add the mesh. I'm just curios how many people use the mesh and if anyone has seen a problem not using the mesh.
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