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

 

[RSKY]

Patrick I like your idea of removing the slab and pouring it at a lower level. My wife wants tile for the new floor but we are concerned with it being cold in the winter. If I cut out the old slab, repoured, at a lower level than I actually needed, then put it joists and a subfloor?????? I can see problems with this but it still may be my best bet. I will be 60 years old in a couple weeks but I think I can handle the labor, don't have to work twelve hours a day if I don't want to. Thanks for the ideas.

RSKY

 

[DFB]

Ok I'm under the assumption this is a shed style roof with the door on the face wall correct? If that be the case you could always frame a gable dormer in the roof over the door so you had more room to raise the header and thus the door. That has been done a lot to make standard height garage door opening in a building eave wall and/or add length... Patrick_g has got me thinking lol!

 

[patrick_g]

Patrick I like your idea of removing the slab and pouring it at a lower level. My wife wants tile for the new floor but we are concerned with it being cold in the winter. If I cut out the old slab, repoured, at a lower level than I actually needed, then put it joists and a subfloor?????? I can see problems with this but it still may be my best bet. I will be 60 years old in a couple weeks but I think I can handle the labor, don't have to work twelve hours a day if I don't want to. Thanks for the ideas.

RSKY

If you are going to pour at a lower level and end up with tile then skip the tapered joists and use the cement type materials and end up with the floor where the wood version would end up and yoiu are ready for tile. After the concrete or concrete like materials are very well cured AND AS DRY AS THEY WILL GET then tape a piece of heavy plastic like visqueen or similar about 3x3 ft with duct tape all the way around the edges. Let it go for a dday or so and pull off the plastic. Judge by the color of the surface of the concrete how much moisture is coming up from the ground. If their is significant darkening or actual dewlike condensation then you have to use tile that will breathe or else it will be popped off of the thinset by vapor pressure of the water vapor coming up through the slab. Porcelain tile is essentially glass and passes no moisture so is at the one end of the spectlrum. You may need to be toward the other end of the spectrum and have better vapor permeability.

Patrick

 

[farmer2009]

Patrick I like your idea of removing the slab and pouring it at a lower level. My wife wants tile for the new floor but we are concerned with it being cold in the winter. If I cut out the old slab, repoured, at a lower level than I actually needed, then put it joists and a subfloor?????? I can see problems with this but it still may be my best bet. I will be 60 years old in a couple weeks but I think I can handle the labor, don't have to work twelve hours a day if I don't want to. Thanks for the ideas.

RSKY

If you really want to do a complete demo of the old pad then I would recommend only digging deep enough to add a layer of gravel then a vapor barrier and a layer of 2" ridgid(sp) foam. Then tile right to the top of the new concrete or have the concrete stamped and stained and sealed. No need to tile over that. If there is a large moisture issue then add some weaping tile under the gravel or in the gravel. Run the weapers outside if possible to avoid a sump box.

 

[ultrarunner]

I had 3" and decided the best way was to float a new motar floor which was just the ticket for my new ceramic tiles... 17 years and nothing has moved.

Slab was really well made and it would have been a job to demo it in the back yard.

 

[Egon]

Remove the old floor. It will be easier than you think. Use a saw to score the concrete into manageable pieces.

At this point you may want to evaluate the ground moisture situation and make arrangements for drainage. You may also have to evaluate the bearing wall footings??

Remove enough of the base to be able to spread in some levelling sand or gravel, vapour barrier, foam and then concrete with embedded heating of your choice.

Finish off using the schluter ?? The orange stuff for the tile laying.

Seems like a lot of work but may be best for long run.

Notice: no mention of permits or codes.

 

[ultrarunner]

When I help by brother put in his patio... we did full footings with extra rebar.

He wanted it flat and I told him it should be sloped away from the house.

He reminded me of that when it came time to make the room a family room.

At least I put in a big header across the back where the kitchen was during the previous remodel... so that part went slick with the header and kitchen vent from the sink already routed out of the way.