basement floor question

[mikejurasw]

(Hoping this is the best forum for this question):

• I am planning a basement re-model (old knotty pine and drop ceiling gone...new drywall, can lights, etc.)
• but it's an older home with a concrete floor sloping gradually to a quasi-central drain
• I only intend to finish 2/3 of the space, so some will remain for "laundry room"
• I want to use liquid floor leveler, but
• the aforementioned drain is within the space I want to level and cover in vinyl/laminate/carpet
• also, can I lay down my treated 2x4 wall plates and just pour that space level?
• How will the rest of the room drain if it ever floods?

Thanks for any advice. Will upload photos/soon
M.Miller

 

[bud16415]

Well if it is dead level it can't hold much water. If there is any chance of water plan your materials around what you wouldn't mind getting wet.

 

[Guzzle]

Can you elevate the floor, maybe 1" at the perimeter & higher at the drain to maintain level? You'd need waterproof standoffs pretty often to prevent floor bounce.

I'd have an inspection port above the drain.
A water level sensor underneath this flooring wouldn't be a bad idea as an early warning. Some may be actuated by 1/16" of water.

IIRC, concrete is somewhat porous so if the ground water touches the bottom surface of the concrete you might have moisture in the air space below the finished floor. In this case a sump pump would have to run continuously.

 

[Steve123]

You might want to look at something like Dricore on the floor, and use a flooring material that is tolerant of the slope.
If you really want to level the floor, I know they make levelling shims for dricore, but you would have to look into whether they can be used for changing a slope, or are more for local levelling.

 

[mikejurasw]

Thanks all. Very helpful. I'm contemplating moving the floor drain to keep it at the bottom of the portion of basement which will remain sloped (and un-renovated), then leveling as close to flat the portion that I'll renovate. This way I think I can put down vinyl or something interlocking without shims. If the slope is substantial enough, should I rough in bagged concrete mix, then do floor leveler over that once it has dried?

 

[Sparky617]

You're going to be hard pressed to feather out bagged concrete thinner than a 1/2". So if you have a deep slope, you could probably use bagged concrete for the deepest part. You'd need to use a primer to get the concrete to bond to the existing concrete.

 

[Guzzle]

I recommend you thrash out at least one plan all the way to the last detail.
You don't want to start this & then get painted into a corner.
In the end you may have to choose between the least offensive plans.

 

[mikejurasw]

Fair point, Guzzle! I'm going to let this one marinate awhile before I do anything.
Cheers!

 

[Fireguy5674]

I saw a remodel of a basement apartment once where they had a similar problem. A drain with slope to it from all directions. They leveled a 2 x 4 that was sitting on the floor at the high side and shimmed at the low end to make it level. They then used a compass to mark the 2 x 4 following the floor taper. The 2 x 4's were ripped along the line transferred by the compass. They did that to multiple boards until they had enough to create a level area the size they wanted. They secured the ripped 2 bys to the floor and used them as a guide to pore floor leveler and screeded along the tops of them. Once you set your compass, lock it and leave it.
I agree with Sparky. Do lots of prep to clean the area and use primer so everything will bond. I have used floor leveler in many situations. Good stuff but not cheap. What do you think the total thickness will be one end to the other? I have used small aggregate concrete in areas deep enough then finished with leveler.

 

[mikejurasw]

Thank you Fireguy! This is exactly what I had envisioned but I didn't know how to get there. This will work in my situation once I get past the carpentry. I still need to lay a few levels on 2x4's to see just how much deflection we're dealing with. Could be 2+ inches, although I don't think I'll need to go all the way to the margins; the slope is mostly in a circle out from the drain in a +/- 6-ft. range. Since the original concrete has been painted, do I need to remove or scratch that up before pouring leveler, or just clean and prime?
Thanks again.
MM

 

[Fireguy5674]

I would say probably need to scratch up paint before priming. I would consult bag and maybe even manufacturer before trying to remove paint from floor. Depending on the paint and amount of area, that can be a real pain. Liquid stripper might be the way to go if required.