DIY Home Improvement Forum banner

1 - 2 of 2 Posts

·
Registered
Joined
·
7 Posts
Discussion Starter #1
Greetings all,

Long time lurker first time poster. I have this dilemma.

We have screen room addition in the back that we are trying to convert into usable living space. The Addition sits on a very solid, stable concrete pad that has 4 feet of footing around it, and i can image is only about 5" of concrete in the middle. The Room itself is about 12 x 16. and the Finished concrete floor (mostly level) and "MOSTLY LEVEL " is another problem that i will need to address but for scope of my question lets assume that the concrete is level.

The concrete pad sits about 10" lower than the finished hardwood floor. Goal of our project is to rework existing floor (which is a drafty and cold carper on 3/4 plywood) and convert it to a solidly build sub floor that can be finished in oak hardwood.

This is Chicago, which has been super cold recently.

I am trying to address Vapor/moisture Flow (from the cold damp concrete) and insulate it at the same time. Whatever I do I will need to work around and still provide 4" ducts to 4 locations within the room. (yes ,that will be a challenge) --- also trying to have a stable enough (SEALED) structure that can successfully hold a hardwood floor.

I ran across this post by highly respectable Steve Baczek on Journal of Light Construction:

https://www.jlconline.com/how-to/insulation/insulating-a-sunroom-floor_o

He recommends a floating floor solution, which was my original idea as well. With the exception that I have plenty of questions…. on my pressure treated 2x4 sleepers. Wouldn't I want to mechanically drill in holes and attach the sleepers to the existing concrete? -- Or as he said, don’t puncture the vapor barrier.
The Location of the Pad in the back of the structure is very prone to sitting in water about 9 months of the year… so addressing the vapor barrier is key.
Also he mentions EPS foam , however I think XPS foam (the FOAMULAR 250) is much more easily accessible for our location) 1” and 2” XPS foam can be ordered via the Green Big Box store.
Also another source mentioned using liquid applied polyurethane sealer to be applied to the concrete itself. Seems to be very high quality material, but also pricey:
https://www.wakol.com/en/Products/Preparing/WAKOL-PU-280

Would I apply the sealer AND also lay down 6mil poly right on the concrete. Cost of poly is very minimal, I guess my question is whether the Wakol sealer is still necessary (at $280.)

To actually build the sub-floor, I was hoping to lay down the 2x4 sleepers, and put down XPS 1.5 “ RIDGID FOAM on the 24” on center or 16” . and them lay down another 2” XPS to break the thermal barrier , as the JLC suggests. . Then I was going to run my mechanicals (ducts, electrical and speaker wire, etc) once that is done, I would continue with placing Joists , around any of the ducts.
Was planning on finishing with a 3/4 “ AdvanTech Flooring .. and then regular ¾” oak flooring strips to match the level from the kitchen.

Thank you for any tips on this! Sorry for the long post -mark
 

·
Registered
Joined
·
28 Posts
I’m in true same situation haha. I tore down an existing structure and started scrims scratch. I haven’t even tackled the interrupt yet being the outside leads to a whole new makeover off siding soffit fascia gutters and the works. I was thinking off using liquidam. It is expensive but sounds about the same as yours product. Then I have Elevated treated 2x6 I was going to space either 12-16” on Center. 4” foam in between joists. Tongue and groove 3/4” ply. I haven’t got any specific answers either. I see this post is older. Have you went through with anything?
 
1 - 2 of 2 Posts
Top