Vinyl plank flooring and bumpy concrete

[pcooper114]

So we're in the final stages of building a poolhouse and planning on laying vinyl plank flooring in the kitchen area. Problem is that the guy who did my concrete did an awful job finishing the concrete. It's quite bumpy and rocky at the surface, so I'm considering my options to even it out.

Originally my thought was to use hardie backer board glued or mortared to the concrete. That feels overkill, but seems to be a perfect solution. I've also considered the self leveling stuff, but my cabinets are already installed, so I don't know if that's an issue. I wouldn't think so.

One thing I've read is that some people have had success with is using sand. I wouldn't use sand to necessarily try to bring one side of the room up and inch or so, because surely it would shift over time. But with all the bumps and ridges, I can see how that might smooth things out enough. Also, I have 10 tons of sand left over from the brick part of the job, so there's that.

Does anyone have any insight?

 

[highup]

The sand trick can probably work underneath a wood plank type flooring because it's so rigid but no way what I think of using it underneath the vinyl plank flooring.
By rocky, do you mean 'gritty', where the aggregate actually showing?
How large is the area and what shape is it? It sounds like a job for a self-leveler but you'd probably want to take down any obvious high spots first.

 

[JPfloor]

I agree, Grind what you can on the high spots. Self leveler would be you best and easiest bet. If you have any experience with a screed and a trowel a slightly less expensive option would be regular Portland based underlayment compound. Sand is definitely not an option.

If that floor in the picture is brand new your mason might owe you a few bucks for the repair…

 

[rugaddict]

Arden feather finish—- on to the next job

 

[C.J.]

First thing is to check your floor for flatness. Mark out any high and low spots and what’s going on with the ridges n such. This will let you know what kind of prep you’re looking at. You can use a level, straight edge or even a piece of base to check your floor to see how close it is to flat right now. Longer is better within reason. 8’ piece of base would work perfect to lay on the floor and see what exactly is going on. What’s it look like when you check the floor?

If your entire kitchen is one big bowl and there is a couple inch gap under your straight edge then who cares about the ridges cus you’re gonna cover them up with self leveler to get a flat floor.

On the other hand if your floor is relatively flat overall but definitely not smooth you could get away with grinding down any high ridges and floating the entire floor a couple or three times to fill in the grooves and low spots.

 

[pcooper114]

Thanks for the insight. I ended up grinding down a few high spots, but then laying Hardie Backer Board under the vinyl plank since it's a small space. Mortared down the areas that were not perfect and it worked out pretty well.