[gizzygone]

In order to conceal plumbing in my basement, I framed a wall about 8" off the foundation slab. Unfortunately on that same wall, we have stairs leading to the outside (covered by a bulkhead). Rather than leave the door recessed 8", I'd like to sit it in the new framing, creating a seamless look.

I figured to close off the bulkhead to behind the wall, I would run plywood from the framing and attach it to the concrete (the last thing I need is water or pests getting behind my new walls).

I was originally going to use construction adhesive to attach the plywood to the slab, but I realized I have to be concerned about water wicking thru the slab into the plywood.

So I'm figuring I could just wrap the backside of the plywood with some 6mil plastic and tapcon it in?

Or would sill-seal be a better option? If I go with sill-seal, can I sandwich the sill seal between construction adhesive and the plywood, or would the adhesive eat away at it?

 

[WhatRnsdownhill]

I think thats a recipe for disaster either way...moisture is going to get trapped either way..an air space with circulation is about the only way if your going to put any kind of wood product against cement..you might get away with it if you use marine grade plywood..

 

[gizzygone]

I think thats a recipe for disaster either way...moisture is going to get trapped either way..an air space with circulation is about the only way if your going to put any kind of wood product against cement..

How would it be any different than the wood-framing they use for the existing in-slab door?

I suppose I could try using PVC trim board, but i figured treated plywood would be far more durable at that thickness.

 

[WhatRnsdownhill]

How would it be any different than the wood-framing they use for the existing in-slab door?

I suppose I could try using PVC trim board, but i figured treated plywood would be far more durable at that thickness.

the slab on the floor usually doesnt have a constant moisture seeping up, the foundation walls are constantly being moistened by rain and if you water any plants around the house...I have seen plenty of rotted raised basement floors done with wood..

 

[gizzygone]

the slab on the floor usually doesnt have a constant moisture seeping up, the foundation walls are constantly being moistened by rain and if you water any plants around the house...I have seen plenty of rotted raised basement floors done with wood..

It's hard to describe for a rookie, so maybe I'm not conveying it correctly?

What I'm saying is that the existing door is framed into the concrete slab itself. They left the form open in that section, and it appears that they added 2x4 framing directly to the slab so they could attach a prehung steel door.

I'm not so much worried about the floor, but I'm trying to prevent water in the slab walls from wicking into the plywood. Seeing as they used 2x4 framing for the existent door, how would plywood be any different?

 

[WhatRnsdownhill]

It's hard to describe for a rookie, so maybe I'm not conveying it correctly?

What I'm saying is that the existing door is framed into the concrete slab itself. They left the form open in that section, and it appears that they added 2x4 framing directly to the slab so they could attach a prehung steel door.

I'm not so much worried about the floor, but I'm trying to prevent water in the slab walls from wicking into the plywood. Seeing as they used 2x4 framing for the existent door, how would plywood be any different?

did they use pressure treated lumber at least? a picture is worth a 1000 words if you can post one..Im sorta not understanding what or where you want to put the plywood..sometimes that wood is removed and a steel framed door is installed and the groove left by the wood taken out of the foundation is filled with cement around the steel door frame to lock it in place..

 

[gizzygone]

did they use pressure treated lumber at least? a picture is worth a 1000 words if you can post one..Im sorta not understanding what or where you want to put the plywood..sometimes that wood is removed and a steel framed door is installed and the groove left by the wood taken out of the foundation is filled with cement around the steel door frame to lock it in place..

I'm not home right now, but I found this picture which is similar to the door I have:

It's hard to tell on mine if it's pressure treated, or just some hardwood. Typically people use pressure treated around here, but the lumber they used in mine appears far too red to be pine.

 

[WhatRnsdownhill]

I'm not home right now, but I found this picture which is similar to the door I have:

It's hard to tell on mine if it's pressure treated, or just some hardwood. Typically people use pressure treated around here, but the lumber they used in mine appears far too red to be pine.

ok and where do you want to put plywood?

 

[gizzygone]

ok and where do you want to put plywood?

Picture 2x4 framing standing about 8" off the wall, in front of the door. I want to re-set the door into the new framing.

But I want to block off the area between the new framing and the existing foundation wall: so I'd run the plywood from the new framing to the concrete foundation.

 

[GottaFixIt]

I'd use pressure treated dimensional lumber.

 

[WhatRnsdownhill]

Picture 2x4 framing standing about 8" off the wall, in front of the door. I want to re-set the door into the new framing.

But I want to block off the area between the new framing and the existing foundation wall: so I'd run the plywood from the new framing to the concrete foundation.

Ah gotcha now..I agree with above, use dimensional lumber...

 

[Mingledtrash]

the presure treated ply wood is fine or dimensional pressure treated. sill seal is the best route it will separate the wood from the concrete and also fill any voids. you could also use construction adhesive. just do not use both as the construction adhesive can denature the sill seal.