Leveling a concrete floor

[RSKY]

Have a sunroom we built on what was a concrete patio. The floor slopes 4" across the 12' width of the room. The floor is two steps down from the main house but even with the added on utility room.

How can I level the floor?

As an added problem the roof slopes to only about 4" above the outside door.

Any ideas.

RSKY

 

[amaxwell]

Have a sunroom we built on what was a concrete patio. The floor slopes 4" across the 12' width of the room. The floor is two steps down from the main house but even with the added on utility room.

How can I level the floor?

As an added problem the roof slopes to only about 4" above the outside door.

Any ideas.

RSKY

We made a sunroom out of our screened in porch, and had the same problem. The guy that layed the tile floor used a mixture that looked like brick morter ,but he said it was for leveling floors. Call someone in your area that does tile work and inquire about this mixture. It started out about 1/2 " next to the house and got thicker as the floor sloped, but my floor only sloped a couple of inches. This also fixed the small dips and rises in the concrete. You would probably not notice a small slope across that distance if they can't get the door to work with the build-up of 4". The floor turned out great hope yours does too!

 

[dave1949]

If the roof is 4" above the door, there is probably a 2x4 header there. I don't see raising the door as a good possibility without building a roof dormer over it.

I suppose you could take 4 inches off the bottom of the door and raise the threshold by that amount. That would give you your 4" of slope back and still have 6'-4" door.

You would need to do something at the base of the walls if you added 0"-4" of concrete across the floor. Might be spendy, but you could cut slate to stand on edge against the wall and glue it, then pour concrete to those like a form. Needs some sort of expansion relief between the stone and concrete.

Slate can be sawn easily with a wet tile saw. You can file and sand it too, to knock off the sharp edges. The angle cut along the floor would be hidden in the concrete, so it wouldn't have to be a real close match.

 

[RDrancher]

You could bring the low side up 2". In 12', the difference wouldn't be too noticeable.

On this former patio floor, I used a product from Mapei Products to bring up the low side 2" in 10'. It's a non self-leveling polymer modified cement product. You can start from featheredge and build up to 3" thick. I think you'd be OK at 4" by adding aggregate to the mix.

I also cut, rebar stitched and repaired a section that used to be a wooden expansion joint using epoxy injection. I removed the baseboard, and used Deck-o-Foam DECK-O-FOAM Expansion Joint Filler - W. R. Meadows to separated the pour from the wall. I used a diamond cup grinding wheel to antique the smooth finish, then acid stained and sealed it. When it was all finished, I put the baseboard back in place and added a piece of quarter round to hide the foam.

Here's the before and after pics.

 

[jfh28]

4" is asking a lot from leveling products........I know it's more work but have you considered cutting the existing slab out and re-pouring it level. This eliminates the door problem. The other alternative would be to cut pressure treated wood tapered joists and install pressure treated plywood on top.

 

[byronlj]

I cut pressure treated 2x6's down to 4" and then ripped them diagonally to created wedged floor joists. Glued them to the concrete and then installed 3/4" T&G plywood subfloor. Turned out solid as a rock.
Dave

 

[DFB]

Yup I would go with PT sleepers shimmed and leveled over the concrete. That's what I did down at the orchard when we had to meet the new food grade standards for food processing. Also fit rigid insulation under the plywood floor so it hopefully wouldnt be as cold as it was standing on the old concrete for the people working there all day. The old barn floor was formed with a pitch better than 2 inches over 20 feet run...it that led out towards a big overhead exterior door. And was so rough it looked like it hadn't even been troweled off when it was poured. I had similar problems with existing gigantic insulated walk cooler doors. They couldn't be raised or cutoff either. What PITA. The doors dictated just what I could do. Originally we discussed using concrete levelers but this is what we ended up with. Overall it came out good and held up well in a commercial setting. No sag or movement and they load up to around 3 ton live load/dead load sometimes. One day I walked in there was like 100 40 lb crates of apples, 8 people and the machinery. I was shocked :shocked: They're rough on that stuff!



Can you consider relocating the door from its present location that would make leveling a straight forward job and eliminate having to cut or order a custom sized exterior entry door

 

[RSKY]

Lots of good ideas here, but none that would work in my situation. I may have to cut out the existing slab and re-pour. I hate the thought of doing that. It will be a huge amount of work.

Thanks to all for your input. Keep the ideas coming.

RSKY

 

[dave1949]

If you remove the existing concrete, you could use patio pavers rather than re-pour.

My guess is you will be happier in the long run taking out the concrete and re-doing.

Are the walls resting on the concrete now? Or is the slab inside the walls?

 

[patrick_g]

You shouldn't have to demo the entire floor, just enough to get down to a level you are willing to accept at the door. There are self leveling cement-like products used for such projects as retrofitting hydronic heat in an existing slab floor situation. This would give you a level floor with a height intermediate to what you have and what you would have had if there were no "fall" when first poured. Someone suggested doing a partial slope remediation to a pitch that would not be noticed. Combine the 1/2 floor removal and lesser slope ideas and get, depending on how you did it only 1/4 of the original slope, Demo part of the floor, pour a cap with half or less fall and the slope will be too small to be very noticeable. If you took out half of the old slab and corrected the fall by one half you would have 1/4 of the current slope. Unless you are playing shuffleboard or holding marbles tournaments that should be good enough. If none of the ideas prior to this post or in this post appeal to you then maybe there isn't a satisfactory answer from your point of view. You may have to accept a compromise and settle for close enough when perfection is unavailable.

Take a little off the bottom of the door, reduce the slope and only have to demo part of the floor. Not a bad compromise.

I personally like warmer floors and like the tapered floor joists with subflooor underlayment idea (1 1/4 inch (I think) T&G OSB. Stout stuff. It is used for floors above crawl spaces and can take a little moisture. Putting down a vapor barrier like products available from Stego Industries, LLC | Concrete Vapor Barrier, Stego Wrap or similar would stop all moisture migration from the bottom side which you will have without the vapor barrier. If you demo part of the existing floor re-pour to the new height (compromise) and leave in a little slope (cut the bottom of the door some too) and you end up with a very stable well supported wooden floor which adds considerable R-value and with the vapor barrier excludes moisture you will end up with a space that is a little less expensive to heat and cool to your desired comfort level. It is altogether unlikely that there is an acceptable solution available via just pouring something like a self leveling product and cutting the door a bit.

If you list what attributes are negotiable and to what extent as well as which are non-negotiable then some of the folks here just might be able to hit on something you'll accept as good enough. Make sure you don't have mutually exclusive mandatory requirements.

Patrick