I am leveling a concrete floor in my sunporch that rest on a crawl that is not accesible. It needs to be leveled by about an 1 1/2″. The plan is to rip 2×4’s down from 1/4″ to 1 3/4″ and cover with subfloor. This room has HVAC and will now be open to the rest of the house through a new 10′ opening. How would one lay or affix the the 2×4’s to the existing concret floor? Liquid nails and screws where possible? Also, can pressure treated 2×4’s be used and should a vapor barrier be put over the concrete first? The floor is currently covered with marble tiles(that will be removed) and they don’t sweat when the temperature drops. We live in Kentucky. Please let me know your thoughts.
Thanks
Replies
How about concrete?
You don't say how large a room, but why not use concrete?
Either a sand mix or a peastone mix for the bulk of it, then feather that into the thinning edges with a grout or floor leveling compound.
Terry
Thanks for your reply. The room is 17x10 and we are not using concrete for a couple of reasons. The room has a 7 foot ceiling (We are going to raise the ceiling to 8 1/2') and a 5" step down. The room has 9 casement windows that are about one foot off the ground and 56" tall. We really need to limit how much we raise the floor because if we raise it too much, people will be looking at the top of the window when standing. If we used concrete to level and then add 2x4 on the flat as floor joist and plywood, we would lose floor height. What are your thoughts?
I think he means that you would use the concrete alone, without any plywood.
Forget the sleeepers and just do SLC, gypcrete or concrete to level it to almost finished level
BUT - I would want to know WHY it is off level that much first. If it is still sinking, you will have nothing but troubles down the road
I would guess that it's an old patio that was (properly) sloped about 1/8" to the foot.
If I were guesing, that would also be my guess, but making some assumptions leads to some drastic errors, so I try not to do it.
So you are suggesting this was an open slab patio that somebody built a room over. If true, that means that a lot of laod was already added to a slab that was not designed to handle the weight unless it was done with thickened edge, steel reinforcement and on compacted soils
Well, re-reading the original post, it sounds like it's an old porch ("over a crawl"). So there would be something resembling a footing around the edge.
But regardless, that's water under the dam (or is it "over the bridge"?) at this stage, since it sounds like the area is already enclosed.
(But it is a good point that full-weight concrete might not be the best idea on a self-supporting slab -- probably lightweight concrete should be used.)
I'd have a sub come in and pour Gypcrete to make the floor level. 2 hours tops start to finish and you' re done. Your way is going to make the floor higher and will be tough to do well.
Thanks for all the replys. Yes, its an old sunroom on a foundation, in a 1950's house. We want to install carpet, should we be concerned about mold growth?
mold
Mold requires food, warmth. and humidity.
Test your slab ( thgat one stil puzzles me with a crawl under it)for humidity by taping plastic 2'x2' over it for a few days. See oif there is sign of moisture under the plastic
Hi Andrew,
I've done what you're proposing (in my case, it was for basements, exterior decks that needed to go over a slab, etc) and have had success with pressure-treated sleepers. I've used a combination of construction adhesive and powder-actuated fasteners (Ramset is one brand). I know lots of people like concrete screws, but for the amount you'll need to install, I'd be groaning at the thought of that many pilot holes with the hammer drill.
As for the vapor barrier, I don't see how it could hurt. The glue would no longer make sense, obviously, as gluing wood to plastic isn't helping much.
On a side note, I've tried PVC (Azek, etc) as sleepers (to eliminate chance of rot), but when ripped down to a narrow width or 1x2, they tend to split very easily.
Justin from FHB
PVC or composites as sleepers is insane
LEVELING FLOOR
I WOULD GO TO BOLAND MALONEY AND GET THEIR ADVICE/ MANY YEARS OF QUALIFIED PEOPLE TO HELP YOU.
THEY COULD ALSO HOOK YOU UP ON A CONTRACTOR IF NEEDED. HAVE A GREAT DAY