self leveling concrete tips

Hi all! I am putting in a new bathroom and will be using vinyl planks that look like wood as flooring (Mannington Adura). I know the subfloor needs to be as flat as possible but in this new bathroom, the concrete was busted up and patched up for the plumbing and it's only kind of flat.

So I've been looking for options and it sounds like self leveling concrete is the way to go and relatively simple to do DIY. Any tips or experience with using this?

My biggest concerns is that the floor currently slopes a bit in one spot towards a floor drain that's just on the other side of the bathroom wall. I don't want any of the leveling compound to get underneath the bathroom wall frame/drywall. And of course definitely don't want to end up with it in the floor drain! What's the best way to ensure it goes only where I want it?

 

Self leveling Compound (SLC) is not fool proof. I does tend to seek its own level but it also will clump and bulge as it sets up relatively fast. You need to prime the concrete first with a SLC primer, let it dry for at least 2 hours before you attempt your pour. Plan on working and massaging the compound to ge best results.

You vinyl planks are fine, other members have used them. However, if you use them in the area of a floor drain and the floor slopes, they will not work.

 

You're right that the SLC will find any little hole or gap and happily flow into it. If there is any doubt that a bottom plate is tight to the floor, I put a small bead of caulk along the plate/floor seam. If there are any holes in the slab, even small ones, fill them with caulk or foam. If there's a doorway and you think the finished height of the floor is such that SLC may flow out the doorway, it's best to build a temporary curb that can be removed after the pour (although that may mean using a threshold under the door). Have some masking tape on hand in case compound starts leaking under a bottom plate or leaking down a hole you missed.

If you need more than a bag or two, have help on hand to mix while you are pouring and spreading. You will need a sturdy corded drill and a big mixing paddle to mix. Have enough buckets on hand so you don't have to stop in the middle and clean one. Premeasure the water for each bag.

Although they call it self leveling, you will have to help it...you can't just dump it in the center and expect it to flow out from there. You have to spread it out to rough depth and level and then it will flatten out and find level from there. Mortar hoe works well.

As Chris said, using the recommended primer is crucial.

 

Thanks everyone! I got the materials and plan on doing this tomorrow (working on prep today). Question - how messy is the preparation of the mix? The bag says to pour the powder into water and I'm wondering if I can do this inside without making a huge mess? It would be nice to not have to carry it through the upstairs and down into the basement but I don't want it everywhere. And do I need a mask to avoid breathing in powder?

 

Well......you get a pretty big cloud of dust when you dump in the bag, although you can minimize it by pouring a little slower. The powder is very fine. Just put down a drop cloth and be prepared to do a little vacuuming afterward to pick up stray dust. Turn off your furnace/AC during the mixing part of it at least.

Definitely wear a mask; not good to breath the dust.

 

I know it's been over a year, but curious as to how this went???