Advice on leveling concrete basement floor.

[nbarbieri]

Hello,

I am building(re-doing) a bathroom in my basement and am looking for advice/opinions on the best way to level the floor before we tile. Unfortunately there is a pretty significant downward slope in the concrete slab from the foundation wall(back wall of the bathroom) to the front. The lowest point is 2.75" over 7' from the rear. We need to bring the front of the bathroom up to the level of the rear. There is a drain tile around the perimeter of the basement and the rough-in plumbing has already been installed and concreted over. The house is 84 years old.

From my own research, some people recommend using a drypack floor mud bonded with a some type of thinset to the slab to bring the floor up to level. Some have suggested drilling into the current slab and pounding in rebar to prevent the new concrete from shifting. Quikrete makes a product called "FastSet Non-Shrink Grout" that may work as well.

All opinions and suggestions welcome. Thanks in advance!
~Nick

 

[kd3pc]

for a small area like this, I would use the chemical bonding product and their crete product. I have used quickcrete stuff in the past, with good results. I would not use the grout of theirs, as it may not work as well as the concrete. Just form it up, and go. In the pic, it looks as if you have already framed the room, and that would result in pouring concrete up against the framing and over it..?? I would not do that.

No mention of what your plans for the rest of the basement, as this process will only address the bath area, and leave the space next to it - 3" out of level at the 7' mark.

bests.

 

[vettex2]

Ardex makes products for this

 

[SunsetsAndFriends]

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[nbarbieri]

for a small area like this, I would use the chemical bonding product and their crete product. I have used quickcrete stuff in the past, with good results. I would not use the grout of theirs, as it may not work as well as the concrete. Just form it up, and go. In the pic, it looks as if you have already framed the room, and that would result in pouring concrete up against the framing and over it..?? I would not do that.

No mention of what your plans for the rest of the basement, as this process will only address the bath area, and leave the space next to it - 3" out of level at the 7' mark.

bests.

Thanks for the advice. As far as the Quikrete mix, would you use the "Floor Mud" product(used for shower pans) or something more like their Crack Resistant concrete mix and the bonding product? https://www.quikrete.com/productlines/crackresistantconcrete.asp

I was actually planning on cutting out the bottom stud(floor plate) that frames around the door and use a piece of wood on the outside of the framing to form a dam to contain the concrete. The concrete will go against the floor plates, but not over them. I'm thinking something to seal that wood from moisture may be a good idea.

As far as the rest of the basement, the plan is to leave the floor alone. The bathroom area has the most drastic slope in the basement but the rest is not bad. It would cost a fortune to level the rest of the area, which is in total around 1000 sq. ft.

 

[nbarbieri]

I recommend using a SLC (self-leveling compound) such as this product from Custom Building Products.

I would use a SLC if I did not have so much slope to level. Using the product in your link would require a lot of bags and would be very pricy. Plus, it says it only levels up to 1.5". I need to level up to 2.75".

 

[SunsetsAndFriends]

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[kd3pc]

.....or something more like their Crack Resistant concrete mix and the bonding product? https://www.quikrete.com/productlines/crackresistantconcrete.asp

I was actually planning on cutting out the bottom stud(floor plate) that frames around the door and use a piece of wood on the outside of the framing to form a dam to contain the concrete. The concrete will go against the floor plates, but not over them. I'm thinking something to seal that wood from moisture may be a good idea.

I would use the crack resistant mix and their bonding agent. Have in the past, and your need will best be answered by this.

The plan for the "form" is good, I would add a plastic vapor barrier piece to the "dam" as a moisture barrier.

bests

 

[mobiledynamics]

Nabarbieri -

You got 2 options....you want cheap and more work, then you're going to have to level it out with regular crete yourself.

Ardex, Mapei, tons others make SLC that will support the height you want and finish to a nice feathered edge. If you're not planning to do the entire basement, but just the bathroom, then at $50 per bag, it's not alot of $$......

SLC is great BUT you must work quick, prep the edges and perimeters beforehand, etc.
It's semi rapid-set, so you need to work quick and this stuff is runny like water ! Awesome stuff though. I redid 1500sq basement with this stuff.

 

[nbarbieri]

Thanks for all the tips guys. Appreciate it. I'll update this thread after I get the concrete poured.

Best,
Nick

 

[DC73]

I've been researching self leveling compounds recently. Many of them can be poured much deeper than standard by mixing with an aggregate. The aggregate also keeps you from needing as much SLC.

DC

 

[nbarbieri]

Yeah, I got the same advice from a tile guy the other day. Apparently that is how he always does it. It just makes me a little nervous not knowing exactly how much SLC I will need before I start the job.

 

[SunsetsAndFriends]

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[nbarbieri]

One option would be to see whether this tile guy you know would give you a hand for an hour to two during the mix/pour. The prep work is the what takes the most time, which you would have all done in advance.

I actually do have a guy that is going to help with the pour, thankfully.

 

[SunsetsAndFriends]

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