I’m a handy homeowner. What is the best way to level a floor? I have a 20 by 10 laundry that is rough and not level. I need to raise the deepest part by about an inch. The shallowest part tapers to almost nothing. I could do it all with self leveling concrete. The $30/bag adds up quick. Filling in some of the difference with screw down Hardi backer boards adds up also. I want to do it right. If that means several hundred dollars of self leveling concrete, that’s fine. What is the right approach?
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What are you going to install as finish flooring?
Ceramic tile. This area is about a quarter of the total ceramic tile coverage.
Also, I have two adjacent areas to level, both about the same size. Should I do both at the same time or separately?
Is the floor not level because it slopes to a drain?
No drain, just cheap/shoddy workmanship on the part of the previous owner.
It's some time since I've used the Mapei self-leveller but I think I'm correct in saying that you can add pea-gravel to it for filling greater thicknesses. That might save quite a bit of material.
I'd do the whole thing with self-levelling compound as it's much simpler when the fill tapers to nothing.
IanDG
Thanks.
Custom also makes a good self-leveling cement called Levelquick that's about $25/bag. It's available at HD. You can read about it at http://www.custombuildingproducts.com/ProductCatalog/SurfacePrep/SelfLevelingUnderlayments/?user=pro&lang=en Check the date codes and get the freshest product. Make sure you overbuy -- you can return the unused bags but it's bad news if you run out of the cement during the pour. You have to have everything ready for mixing because the working time is less than 15 minutes -- more like 5 minutes. Make sure you use SLC primer on the floor, and put expansion strips around the perimeter of the room. I uses sill seal or foam wetherstripping for expansion strips.
Yes, you can use pea gravel in the deep end but don't overdo it because you don't want the gravel to stick up over the top...
Read here for more info:http://johnbridge.com/vbulletin/showthread.php?t=1807
Billy
Edited 1/27/2005 10:50 am ET by Billy
Edited 1/27/2005 10:50 am ET by Billy
Edited 1/27/2005 10:52 am ET by Billy
You guys are great. Thanks for the help.
Since you are doing 3 rooms which are about 10 x 20, do yourself a favor and get a 4' and a 6' level. If you can borrow a site level or are willing to spring for a laser level ($250.US) all the better.
Self-Leveling Concrete is one way to go, however it is $$$ and requires some experience and prep work. Regardless of your experience, it will end up smooth but level is determined by how you work it (experience). It also requires about $200 of tools you won't be able to use for anything else. If you don't spring for the tools you will end up with a disaster. BTW, p-stone will help decrease the cost but then you'll have another step, supplier, and variable when applying the SLC. You will also need 3 people who can work VERY well together. As for prep work - you will need to remove the top layer of existing concrete to provide a proper bonding surface for the SLC. Ever use a shot blaster before?
Another method would be to use 1/2" and 3/4" CDX plywood or /4" and 1/2" cement board or Hardibacker as fill. This is relatively inexpensive and covers a large area at one time. The nice thing about cement board is the you don't have to screw it down if the existing floor is concrete.. Just apply it with thinset. The plywood will have to be shot into the floor if it is concrete. As for the Hardibacker I have only used it once and will let others tell you how to apply it to concrete.
You can then skimcoat the floor with thinset. From there, you apply your tile. DO NOT use the thinset as a build up material. It should not be applied greater than 1/4" thickness.
This is a big area for a DIY'er so be sure to have a laborer with you. He/ She can keep the tiles nearby, mix up the batches of thinset, help strike lines and determine level.
F
Thanks for the help. I'm not doing the tiling, just leveling.
I just did this last week, using LevelQuick. I was pretty meticulous about reading and following directions, and didn't find it to be all that difficult (I'm a DIYer, not a pro). I recall the bag said you can add another layer within a few hours - if you miss the window, you have to wait 12 hrs and prime between layers. I used their primer over the plywood subfloor - a little goes a long way - I bought a quart, diluted a cup per their instructions, and easily covered a 30sf area.
I didn't buy any special tools at all. I used caulking rod stapled around the perimeter (and around openings like the toilet hole and heat duct) - this worked pretty well, but the stuff will find ANY gap and run through, so make sure you fill all cracks and holes in the floor. If I had it to do again, i would use the metal lath, and i would run a trowel over it to help it find level - it gets pretty level, but I think surface tension keeps the fluid from running to a 'feather' edge, so it isn't perfectly level. Imagine a drop of water on the counter, with a meniscus (I think that's what it's called). Or you could just try to be less obsessive about these things than I am.
Definitely get the paddle for your drill - don't try to do this by hand - I put the water in a 5 gal bucket, add the whole bag of cement - no need to add it gradually - immerse paddle and mix - watch out for dry clumps stuck to the inside of the bucket. In my case, I discovered I needed a second bag, and easily got to HD & back, mixed it and added it while still in the allowed window of time per the label.
The biggest problem I had was that the low spot was at the door, with the high spot in the far corner, so it took some gymnastics to do it - I threw a couple blocks of wood on the floor as stepping stones, and pulled them out behind me as I worked.
Good luck! Bill.
It helps if you damp down the sub-base first before pouring the self-leveller -- just enough to kill the suction a bit -- otherwise the water is absorbed from the levelling compound before it has a chance to fully level, especially where it gets really thin.
If you wait until the water has gone from the top surface of the levelling compound then feather the edges you'll do away with the meniscus.
IanDG
Thanks for that info - it makes sense, although I thought the primer would prevent the water from wicking into the plywood.
My job was still quite level - i was able to use the thinset to 'fix' the edge where it didn't feather out - everything came out great.
Thanks, Bill.
If you are going to tile then I would pour SLC, Self Leveling Compound. Custom makes a good one called LevelQuick. There are others which are just as good. It is expensive at about $30 a bag. You will need some help to install it, as all of it has to hit the floor at the same time, so if you have 6 bags, then all have to be mixed up at the exact same time, and they can not sit in a bucket. They set up in about 5 minutes, and it takes 2 minutes to mix it up. That leaves you with 3 minutes to dump it on the floor and smoosh it around a tad.
I mix up 2 bags per bucket. If I have 6 bags, then I get 3 helpers, 3 buckets, 3 drills, and count down and mix and dump. No cold joints allowed.
If the thickness is over a half inch, I would install diamond lathe on the wooden subfloor.
Oh, and use their primer and follow the instructions to a "T".
Good Luck.
Regards,
Boris
"Sir, I may be drunk, but you're crazy, and I'll be sober tomorrow" -- WC Fields, "Its a Gift" 1934
I don't think I would use the SLC as it is very $$ and you have a big area to fill and I am not sure how strong it is.
Drill holes in a grid pattern every two feet or so and install tapcon screws adjusting their height with a level. Pour a sand mix concrete with a bonding agent and trowel smoooth so that the concrete just covers the tapcons. Haven't tried it myself just read about it here. Sounded like a good idea.