5

I have a concrete basement floor that was constructed about 18 months ago. In the home construction process the workers tracked in a significant amount of dirt (topsoil?) and the entire basement floor now has a thin coating, more or less. It has not been sealed. I'd like to clean the surface, then put down a 6 mil vapor barrier, then a floating LVP floor.

I've tried several different methods to clean the floor. They all seem to just smear the dirt around without fully bringing it up. We've tried power washing, a baking soda mixture with water and mop, vinegar mixture with mop, dish soap and water, and nothing seems to help. Dry rubbing it with fuzzy felt removes quite a bit of dirt, but it still leaves a lot. It seems the dirt is attracted to the concrete and doesn't come up easily. Is a static attraction involved somehow? There's no grease, oil, or other contaminants, other than plain dirt. I was hoping there would be a simple way to just remove the dirt.

I understand sometimes an acid wash is used to clean before sealing, but I was hoping to leave the concrete unsealed under the vapor barrier.

I would appreciate any ideas as to what to do to remove the dirt, or if it is even necessary.

5
  • 1
    IF you're going to put LVP over it, then why is it not sufficient to just vacuum the floor and carry on with the LVP installation? Commented yesterday
  • 1
    Is there any chance the dirt under the vapor barrier could get damp and attract mold? That's really my only concern. If not, I am fine with having a little dirt under the vapor barrier. Commented yesterday
  • 2
    It's not going to get any more damp that the concrete it's resting on. Dirt doesn't attract dampness if it's not already damp there. Commented yesterday
  • 4
    The most puzzling is that you used so many solutions, a mop being one of them, but using a vacuum cleaner (or at least a classic broom) was never an option. Commented yesterday
  • 1
    Have you tried dry mopping it? And by that I mean the mop is barely wet, just enough to pick up dirt and moisture, but not enough to put any real moisture down. The effect is that you pick up stuff from the floor, and then you use the regular mop bucket and water to wash off the stuff you picked up, then squeeze/wring all the water out of the mop before continuing to mop the floor. Commented 10 hours ago

2 Answers 2

9

You're going to bury it under vapor barrier and flooring, so it really does not need anything more than removing large dirt that a vacuum or broom would pick up. What it looks like under there affects nothing going forward.

If you insist on it being clean anyway, pressure washer to loosen it and a wet shop vac to suck it up, unless you have a sump or floor drain to get the water out. However, there may still be staining from organic materials in the soil. A stiff bristle broom/brush is another approach to loosen the dirt. The shop vac (or a floor drain) to remove the dirt and water mixture before it dries is essential.

2
  • 1
    +1 For the wet shop vac. anything else will just spread the dirt around. Commented yesterday
  • IMO if the intent is to remove the dirt, a carpet cleaner (e.g. Rug Doctor) may do the trick—water and bristles to loosen the dirt, vacuum to suck it up. Should leave less water on the floor to deal with. Commented 19 hours ago
8

I agree with others, there is no need or advantage to making the floor perfectly clean before installing your LVP.

Additionally if water was used for cleaning it may be retained in the concrete for a period of time. If that was done it would be prudent to allow a good drying time (a week or 2) prior to adding a vapor barrier and the flooring.

You should also consult the specific installation instructions for the product you plan to use. Some do not recommend a vapor barrier under their product. The product itself acts as the barrier. Best to check first.

Your Answer

By clicking “Post Your Answer”, you agree to our terms of service and acknowledge you have read our privacy policy.

Start asking to get answers

Find the answer to your question by asking.

Ask question

Explore related questions

See similar questions with these tags.