Should you a use self leveling product over the slope towards a drain in the concrete floor in basement bathroom? We are wanting to install luxury vinyl plank in the bathroom and most sites say to have a perfectly level floor for it. The problem is, the concrete was purposefully made to have a slope towards the drain (built in 2015). Should we level it first or is that a mistake? I’d say the lowest spot is about 1” difference. The bathtub was installed with shims to compensate. I don’t want it to be obvious that the flooring isn’t level. Can someone please help me on what I should do for this? enter image description here

  • it'd be problematic if the drain was in the centre of the floor, but as it's to the side you may get away with it.
    – Jasen
    Dec 4, 2018 at 7:49
  • 3
    It's probably more important that the surface be flat without bumps and ridges or a change in slope. A constant slope in one direction shouldn't be a problem.
    – brhans
    Dec 4, 2018 at 15:13
  • I agree. It's not the degree to which the floor is level, but rather the flatness of the floor that is crucial here. There may be some issues if the slope gets more bowl-like right near the drain, (hard to tell from the picture) but if the whole floor gently slopes, you should be fine I think.
    – gnicko
    Dec 4, 2018 at 20:17
  • I would go with tile , if you want a warmer floor install a heat mat under the tile. Plank flooring won't drain well and with the slope eliminated the drain is useless in my opinion and I would plug it and level / flat the floor so your planking system would work. Note make sure to get a product made for wet use. My daughter covered a kitchen and a water pitcher was dumped she got it cleaned up but the laminate started falling apart.
    – Ed Beal
    Dec 4, 2018 at 23:25
  • It would look weird, and be weird, to have a floor drain and no slope toward it. Jan 17, 2020 at 14:52

2 Answers 2


Old question but to give a correct answer... You don't level basement floors - PERIOD.

You have two options:

  1. Add a subfloor and shim that to flat - dricore squares are an example. The problem with this is not the bathroom, it is the bathroom floor will be 2" higher that the rest of your basement.
  2. Buy flooring that you can install over this. I have installed many many basement bathrooms that had slanted floors (they all do). I have used pure vinyl (waterproof not water resistant) planks and they for sure bend enough as long as the floor is pretty flat. The planks are very high end and can look however you want.

This is a very typical basement bathroom. The water in your basement must be able to drain. It isn't just for the bathroom but it could be sloped for a good part of the basement to here. You don't get to just "level" it.


The problem isn't level, it's flat. Your flooring simply won't accommodate the compound bends that a dish in the concrete presents. You'll get open gaps at the joints and the tile may lift, creating voids underneath.

You'll want to investigate whether you can heat and bend your flooring to make it conform to the shape needed, or whether you can make extra cuts to allow it to fit the floor.

If you decide to level the floor, cut a disk of material the same thickness as the repair and slightly larger than the drain. Tape it down securely to seal the opening. Make your patch, then install a cleanout cover over the drain. You could also extend the drain with the right parts.

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