Ouch. In my neck of the woods (expensive Canadian city) I would expect $3-$4/sf. That would be for the labour (grinding) and for most of the leveling. My concern is the AGE of the concrete. Is any of this at or below grade (ground level)? If it is, you could be looking at more because the concrete might be difficult to get new stuff on top. Slabs (at or below grade) of that era were NEVER sealed underneath = moisture issues.

And vinyl really hates underpad. Eco-cork (did you know it is 90% + of foam and only 10% cork??...yah...talk about cashing in on the 'cork' fad without having to pay for it in the product) is not rated for LVP.

And any LVP with existing backing is NOT allowed more. That's the biggest issue with vinyl. It is not laminate. It does not behave like laminate. It is thinner than laminate and the click-edges are more delicate than laminate. Which is why a near-perfect subfloor is needed for vinyl.

If you were to 'guestimate' $5/sf for the subfloor prep, you *should be safe.

It will cost anywhere from $3-$7 psf. Depending on the condition of the subfloor. It can cost more.

Your floors will be around the $5.00 mark. Needs grinding first. If, it is really bad, then you’re looking at the $7.00 or more.

Yes, the floor needs to be leveled before doing lvp. The lvp will not stay clicked in if you do not have a level floor.

LevelQuik works well if the perimeter of the room is consisent height, but remember that it all depends on gravity. You need a full perimeter border around the area you want to level, and the poured concrete will find the true level point in that entire area. You can't make the floor slope in any direction. It has about the consistency of cake batter, or even thinner.

LevelQuik is also quite expensive for a large area, so do your estimate ahead of time. For example, we added about 1" to level a fireplace hearth and IIRC it took 2+ 50 lb bags, at about $28 a bag. If you use RS (rapidset) you do not have very much time before it starts to set up, so you need a good sized crew to keep the process going for a larger floor.. However, it sets up quickly and is a truly level surface.

Bruce

Thank you all, this was very helpful!

Luckily the unit is on the second floor, so it is above grade. We had previously installed the LVP in a bathroom remodel, after chipping up all of the leftover mortar to get an even subfloor. In this case, the contractors doing the kitchen renovation installed the LVP without leveling the subfloor. We aren't living in the condo, so we did not notice until a week or two after the floors were installed when we realized you could feel how uneven it was. After several weeks of insistence that it was just movement associated with a floating floor installation, they had to remove several planks they cut too short, and we were able to confirm the subfloor had not been leveled.

They still tried to say it wasn't necessary to level the subfloor, but when pressed offered the eco-cork as a solution. It seemed like this was counter to BOTH the LVP and Eco-Cork manufacturers' specifications, but I wanted to confirm this wasn't sort of a standard, "off-label" solution.

Looks like we will be finding someone else to prep the subfloors!

I hear ya'. Subfloor prep is long, dusty, tiring and requires multiple visits to the space. If you didn't pay for it (or even discuss it) then the installation company doesn't do it. What *should have happened is: they call you and tell you, "Uh oh. We've got a problem. This concrete needs work. I will come up with a plan and a quote for you in the next day or two."

That's when most homeowners get suspicious that their reno company is trying to jack up the price. And then the questions start to fly.

This is very common. If the quote didn't include subfloor prep, then you got what you paid for (tongue firmly in cheek). What bothers me is they have NO IDEA about vinyl. This tells me they think vinyl is identical to laminate. And THAT'S what upsets me the most!

You are right to move on to find someone who knows about flooring. The reason you are moving on is because these guys are clueless about A: Flooring and B: vinyl flooring.

It isn't the 'lack of subfloor prep" that bothers me. You didn't get a quote for it....so it wasn't done. That bit is 'fine'. The fact they tried to hide their total lack of knowledge about flooring and vinyl flooring especially is the MOST DISTURBING part about this.