[wattsroy]

I have done lots of tiling on good sub-flooring, but for my next home project I am tiling over a concrete floor in my basement that abuts a stone foundation. The problem is there used to be walls with studs and lathing that we have removed and now have about a 4" gap between the concrete and the stone foundation. My gut is telling me not to tile over the empty space but how do I fill it? There is a 4" trench at the edge of an entire room... all 4 sides. Should I fill the trench with concrete or tile over this space with the idea that no one will ever walk along the wall?

 

[67IreneRoad]

Ciuld be the trench is to collect water during melts, heavy rains etc. Stone foundations are usuallly pourous. Do you have any history there in all seasons?

 

[wattsroy]

It has always been dry. It's where the old plate was and someone did a concrete floor later that aborted the wall (lathed wall) that is now gone. Question is, how do I fill that in (if at all) before tiling the floor?

 

[Nealtw]

I would make sure it was 3 inches deep make sure the stone and floor edge a clean
Put a foam strip on both the side of the floor and the side of the wall. Some where in that 3 inches and then fill it with concrete. The foam tape will help seal it fom moisture and gasses from below.

https://www.homedepot.ca/product/m-...VhsVkCh3e7gkLEAQYAiABEgJLCPD_BwE&gclsrc=aw.ds

 

[huesmann]

Gonna assume you mean "abutted" here...

 

[wattsroy]

Neal, thank you for a solution. When you brought up a vapor barrier are you saying I should put something like a tyvek in the trench?

Huesmann, voice to text is great. Lol

 

[Nealtw]

Neal, thank you for a solution. When you brought up a vapor barrier are you saying I should put something like a tyvek in the trench?

Huesmann, voice to text is great. Lol

It is common to put sheet poly under the slab but if you don't have under the rest of the floor it would be pointless for this strip .
If you had a water problem with the wall you would drape the wall with poly down under the floor but that doesn't seem to be needed.

 

[wattsroy]

Couple more pics with better lighting.

 

[Nealtw]

Couple more pics with better lighting.

What is the wood holding up, we would like to get that out of the way

 

[wattsroy]

Pic 2

 

[wattsroy]

That wood is the only stud left from the old wall that have the lathing, but it is attached to some stairs so I might change it out with a decorative stud. After planing these old pieces they are old growth spruce and look really good.

 

[Nealtw]

That wood is the only stud left from the old wall that have the lathing, but it is attached to some stairs so I might change it out with a decorative stud. After planing these old pieces they are old growth spruce and look really good.

So the wall was holding up the landing?

can you take a picture of the framing under there? Looking up?

 

[wattsroy]

Looks like stairs supported by a major floor joist. The stud is just tacked. Stud is very loose and rotten at he bottom.

 

[Nealtw]

Looks like stairs supported by a major floor joist. The stud is just tacked. Stud is very loose and rotten at he bottom.

You don't want anything like that in you new concrete. :wink2:

 

[wattsroy]

Looks like stairs supported by a major floor joist. The stud is just tacked. Stud is very loose and rotten at he bottom.

 

[wattsroy]

So when I foam and fill this trench, how should the tile (a ceramic fake slate pattern) address the stone wall? Or obscure that edge with baseboard? Ideas?

 

[Nealtw]

So when I foam and fill this trench, how should the tile (a ceramic fake slate pattern) address the stone wall? Or obscure that edge with baseboard? Ideas?

I think i would just leave it until after you have done the floor.

maybe just tile up close and fill to the stone with mortar or grout or draw a straight line and finish the edge with some small tile or stone.