Does anyone have any experience with Mapei Self Leveler? If so, I'd appreciate your thoughts on my project and any lessons learned or tips.


I'm converting a 2 car garage (19' 2" x 16' 6") to living space. After removing the garage doors/frame and pouring a brick ledge in their place, I'm pouring 13.5 cubic feet (finished mixed volume) of Mapei Self Leveler to level the garage floor.

The Self Lever instructions are to mix one 50 lbs bag at a time with 5 gallons of water for 2 minutes before pouring it onto the floor. It says that for best results you want to work with a continuous flow of wet material to avoid trapping air or creating a cold joint between batches. Since I'll be pouring 27 batches, even with a team of people mixing more than one batch at a time, I'm worried about how continuous I can realistically keep the pour.

The specs list the flow time at 10-15 minutes. Does that mean it's completely workable for only that long? The set time 4 hours.

I'm renovating most of the house I just bought and doing the work myself (which is no problem). I had a bid from a local company to do the brick ledge and floor for me (in the interest of time) but when I called to execute the quote they decided to double the bid, so that's not an option anymore and I'll take this part on of the project as well.

Look for and Ardex k-15 product. You will be happier with the result. It's what the pros use. If you can read, you can install k-15.

I will say it you use the mapei materials, follow those instructions or when it fails they will inform you, that it was not installed properly, so tough luck.

Any self leveling products will need to be installed exactly as the bag says or you will be on your own. If you would like to pm me, I would be happy to give you some options for what might work best in your situation.

I used about 11 bags of this in a bathroom and closet renovation. My only suggestion is to add slightly more water than the recommended. I believe the bag says like 5 qts, I put in 6-7 qts. It helps it flow alot easier.

Be careful adding more water than the directions say. The material will not meet its designed compressive strength. Think of it the same as concrete. Over watered concrete with "flake".

Mapei makes good products that win a lot of professional jobs thanks to more competitive pricing than Ardex. K15 is the tits, but Mapei is no slouch.

-What is your pour depth? What mixing container will you use? Deeper pours are harder to keep up with when barrel mixing. If 1" pour, 2 teams of 2 (mixing and pouring if using 15 gal mixing barrels) plus 1 person finishing shouldn't have a problem keeping up. A powerful drill like a Milwaukee Hole Hawg would be beneficial; standard drills will get bogged down and burned up quickly.

-Water demand for a 50lb bag is 5 QTS, not gallons.

-You don't mention surface prep, but mechanical profiling of the substrate and proper priming is of vital importance.

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Mapei makes good products that win a lot of professional jobs thanks to more competitive pricing than Ardex. K15 is the tits, but Mapei is no slouch.

-What is your pour depth? What mixing container will you use? Deeper pours are harder to keep up with when barrel mixing. If 1" pour, 2 teams of 2 (mixing and pouring if using 15 gal mixing barrels) plus 1 person finishing shouldn't have a problem keeping up. A powerful drill like a Milwaukee Hole Hawg would be beneficial; standard drills will get bogged down and burned up quickly.

-Water demand for a 50lb bag is 5 QTS, not gallons.

-You don't mention surface prep, but mechanical profiling of the substrate and proper priming is of vital importance.

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Yep. This is VERY accurate. This Ag has done it before.

Pay close attention to the tech data in regards to floor prep. Also, most of these overlays require the addition of aggregate if your depth is going to exceed 2".

Thank you vey much to everyone for the feedback. The Ardex looks like a great product too but I think I'll end up using the Mapei since it fits into the budget a little better.

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-What is your pour depth? What mixing container will you use? Deeper pours are harder to keep up with when barrel mixing. If 1" pour, 2 teams of 2 (mixing and pouring if using 15 gal mixing barrels) plus 1 person finishing shouldn't have a problem keeping up. A powerful drill like a Milwaukee Hole Hawg would be beneficial; standard drills will get bogged down and burned up quickly.

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On the low end of the garage the pour will be just over 1" deep and on the shallow end it will be just over 1/8" deep. The 27 bags will give me enough volume for the area. The old garage is just a step lower than the rest of the house. I'm want to maintain a step down into the new room so I'm not looking to hit a particular height with the new floor... just level, and thick enough on both ends to ensure the integrity of the finished product.

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-Water demand for a 50lb bag is 5 QTS, not gallons.

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No idea why I typed gallons. I definitely read quarts off the instruction sheet but thanks for making sure I caught that.

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-You don't mention surface prep, but mechanical profiling of the substrate and proper priming is of vital importance.

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Yes, I didn't mention profiling but I did see it in the instructions. Good ot know that it is vital and not a step to be skipped or rushed. Fortunately, the existing surface is very clean and crack-free (really in remarkable shape for a 55 year old garage floor). The 'Primer T' that is used to prepare the profiled floor to receive the leveler calls for diluting it with water when applying it to profiled concrete. The 'Primer T' specs say that 1 quart covers 50 to 100 sq ft of surface (i'll estimate conservatively and say it covers 50). Am I correct in understanding that is undiluted, and that if I mix the primer and water at a 1:1 ratio that I should use 3.5 quarts of primer and 3.5 quarts of water (so that 7 quarts of finished solution overs 350 sq ft)?




I think the only outstanding question I haven't found an answer for is about expansion joints. The Mapei instructions say to "provide for expansion and control joints where specified, including the perimeter of the room, columns, supports, and other pedestals" and to "cut joints in the Self-Leveler Plus at least 1/4" wide within 24 hours of application." There aren't any expansion joints on the current garage floor... it was all poured with the slab foundation of the house. Does that mean I won't need any expansion joints through the middle of the newly poured surface. I do not have any columns/supports to pour around... the new floor will go to a new brick ledge on the ~1" deep edge, an interior wall (sole plate) on the ~1/8" deep edge, the existing brick ledge on one side, and the existing foundation (elevated higher than the current garage floor) on the opposite side. Is leaving a 1/4" gap between those boundaries and the poured leveler for expansion control an acceptable approach? I'm installing click-and-lock engineered hardwood (with a pad and moisture barrier) over the new surface if that makes a difference.

As for the control/expansion joints, Mapei just wants you to honor any existing joints through the topping, so you are correct in assuming none in the field of the pour. As for the perimeter, it sounds like you shouldn't need any there either, so long as you are pouring over 1 continuous slab. The instructions are more for commercial applications where columns are often isolated from the foundation and there are more control joints and separations to be cognizant of. Just prime your boundaries with the rest of your floor and pour to them.

As for the primer, I would suggest running at least 1 coat of 2:1 first, to really soak in to the concrete. Then run your 1:1 bonding coat(s). You can't overdo the primer, and the more the better. I usually run a minimum of 3 coats on profiled concrete because the concrete WILL outgas through your wet topping and create little volcano holes in the finished product and more primer will minimize this. Also, spend the most time prepping/priming the thin area, as it is much more sensitive and prone to failure than the deep area.

I'd probably go with a 2-gal primer kit, if I were you. Make sure you have enough to not be stingy with it.