Questionable contractor install of ditra heat duo mats on concrete

Ask your bathroom related questions here
Post Reply
Markw
Posts: 2
Joined: Sat Nov 09, 2019 6:17 pm

Questionable contractor install of ditra heat duo mats on concrete

Post by Markw » Sat Nov 09, 2019 6:21 pm

My contractor is installing radiant heat with the ditra heat duo mats on concrete slab. The mats went in today but there are two things that make me think he didn't do it right.

First in some areas the mats seem properly adhered to the floor but in others there is noticeable give when I press down on it.

Second, in most places the mats go snugly up to the wall. In others it's a good inch away from the wall. I asked him about it and he said he could just put float under the part missing the mat. In my mind that would lead to potential cracking since it defeats the purpose of having the mats in the first place.

Am I worrying to much or will I end up being disappointed if I don't have him start over?


User avatar
Shannon
Posts: 13533
Joined: Fri Nov 25, 2011 11:58 pm
Location: Canada
Contact:

Re: Questionable contractor install of ditra heat duo mats on concrete

Post by Shannon » Sun Nov 10, 2019 9:57 am

The space against the wall I would not be too concerned about as long as you are not using small tiles but the mat should not be spongy when you walk on it. If the concrete had dips in it they should have be levelled out better before the mat was installed. I would say that anything more then 1/8" is too much. If there were dips the mat may have lifted before the membrane was cully adhered and dried? I would point out these spots and see if the contractor even noticed them?
If you've found our videos or website information helpful, please considering making a donation using PayPal or pledging us on Patreon

Markw
Posts: 2
Joined: Sat Nov 09, 2019 6:17 pm

Re: Questionable contractor install of ditra heat duo mats on concrete

Post by Markw » Sun Nov 10, 2019 11:47 am

The floors were leveled and didn't look like there were any dips more than 1/8". I think the sponginess is from the rigidity of the mat in those unadheared spots rather than any dips in the slab that weren't properly addressed.

User avatar
Shannon
Posts: 13533
Joined: Fri Nov 25, 2011 11:58 pm
Location: Canada
Contact:

Re: Questionable contractor install of ditra heat duo mats on concrete

Post by Shannon » Sun Nov 10, 2019 12:13 pm

The mat fleece must be adhered to the floor
If you've found our videos or website information helpful, please considering making a donation using PayPal or pledging us on Patreon

Post Reply