Leveling a bathroom floor...

[Triplegreen500]

So, I'm making progress on my rental renovation. Bathroom time. Question for builders/plumbers in the group (I'm "handy", but don't do this for a living or anything).

Toilet is about 16" from exterior wall. Cast iron pipe, not moving it. Floor drops 7/8" within 22" of the exterior wall, then levels out. It's the joists - they sag in the first 12-18" from the foundation, and level out. Old house (1952).

Subfloor is old-school diagonal 1x6 plank. Over that, is 3/4" thick hardwood. Over that is 1/8" linoleum tile. Over that, was 1/2" plywood and ceramic tile on top of that. I plan to use actual 1/2" backerboard, then ceramic tile. That should get me back to flange height so I can install a stable toilet.

Question is - the hardwood was rotten around the flange (73 years old...no surprise there). I have already cut it out as needed and exposed the subfloor. Subfloor is...decent enough. The sewer pipe comes up immediately next to a joist - as in, touching it. I could either:

1. replace the hardwood with some modern OSB for strength (on top of existing subfloor), stopping it where the floor starts to slope upwards (just behind the flange), and fill the remaining space with self-leveling filler

2. simply lay down some plastic (to cover gaps in the subfloor), and fill it all with self-leveler.

I would use the self-leveler only to the height of the existing/remaining hardwood and linoleum, so I could put my new layer of backerboard and tile on top and have it be a level surface for the toilet.

I'm not concerned about lots of weight bearing behind or next to the toilet - it's a 44-inch wide area and the toilet backs to an exterior wall. Nobody will be walking there. And again, there is a joist immediately next to the drain pipe - and I could frame in a second one on the other side of the pipe, by bridging joist-to-joist underneath, and then boxing that in next to the pipe. I think I'm good on support...I just need to level it properly. The levelers say they want to be used on concrete substrate...but again, it won't be a trafficked area as far as weight goes, so I think this won't be as much of a concern? I can shore up underneath the subfloor as needed, to help stabilize it without changing its height...but I can't see there being enough traffic in the area to ever crack the leveling sealant.

I won't be able to use physical fasteners through the backerboard into the leveling stuff...but a) the toilet will hold it down, b) there will be base moulding all around, at the bottoms of the walls, and c) I can use adhesive to help secure the backerboard to the leveling.

Crazy? Stupid? Or...just might work?

 

[RR Fan Dan]

Strap the drain pipe to the joist. Fill the gap wit 3/4 hardwood, not osb. This will also help

 

[Triplegreen500]

Any thoughts on the self leveler stuff? If I just lay ply on the subfloor, it'll be nearly an inch out over a 22 inch run.

I need to go from like 3/4 to 1/2 to 1/4 as it gets closer to the wall...should I fill those voids with the self leveler?

On top of either the voids, or the leveler, will be 3/4" of backer board plus the actual tile and adhesive....

 

[68-500]

Is the toilet flange level or does it follow the floor? I think id be tempted to fix all rotten flooring with layer of plywood then concrete board then finish the entire floor. If you try to level 1 portion and not the other you will have an unsightly bump or recession somewhere. Can you jack up the floor under the bathroom?

 

[Triplegreen500]

The bathroom itself is level (as is the flange). The floor drops that inch in the first 22 inches from the wall, and levels out. More like a flat floor that ramps up at the exterior wall end, if you will. It isn't the floor that's out of level, it's the joists - and no, I'm not going to shave the tops down to level them. That's too sketchy, even for me!

Floor joists are 2x12, from 1952. I ain't jacking anything up and getting a level result. Best I could do is put a post under joists in the basement to prevent further sag...but not gonna lift anything. It would just raise the "bent" part is all, it won't straighten out.

Level is...level. subfloor on the left, hardwood and linoleum on the right (you can see cut ends at top)

Old but solid cast iron pipe (yes, I'll install a repair flange)

Subfloor is passable...orange stripe is the joist. I think with 3/4 ply plus 1/2” cement board plus the tile it'll be plenty strong, I just need to level underneath the cement board.

 

[RR Fan Dan]

Floor joists are 2x12, from 1952. I ain't jacking anything up and getting a level result. Best I could do is put a post under joists in the basement to prevent further sag...but not gonna lift anything. It would just raise the "bent" part is all, it won't straighten out.

Plenty of old houses here in my little historic area of Virginia. Way older than 1952. We jack them all the time to fix unlevel and sagging floors, including mine. It’s a common practice.

I don’t have an experience with the self leveling stuff. Adding more weight to the floor is just going to exasperate your problem in the long run.

 

[1STMP]

In agreement with @RR Fan Dan.
Fix the root of the problem. Anything
else is just a bandaid.
@Kern Dog could offer some
insight. He's probably seen more
of this than he cares to admit.

 

[demonram]

Why not sister 2x8’s next to all the sagged joist. Make them at least 6’ long. It will do two things, straighten out the joists and strengthen them. As far as the leveling compound, don’t do it! It will crack out, especially over plastic. It has to bond to the surface. Take out the original subfloor, sister in the 2x8’s and be done with it. Kill two birds with one stone. I’ve done it many times and that is the best way to go.

 

[Moms68]

I had a very similar situation in my own house (built in 1954). The cast iron drain pipe in the basement was supported by metal strapping to the floor joist next to the toilet and it pulled the joist down due to the weight over all those years. I jacked up the pipe in the basement and supported it with a 4x4 post going down to the concrete floor.

Leveling compound will work great when you've got things within a 1/2" or so.

 

[Hey-O]

Why not sister 2x8’s next to all the sagged joist. Make them at least 6’ long. It will do two things, straighten out the joists and strengthen them. As far as the leveling compound, don’t do it! It will crack out, especially over plastic. It has to bond to the surface. Take out the original subfloor, sister in the 2x8’s and be done with it. Kill two birds with one stone. I’ve done it many times and that is the best way to go.

I agree. I've used two part pour epoxy on concrete, that would take fork truck traffic, could be poured as thick as you wanted and was stupid expensive. Floor leveling products require a solid base to work well. It's not about foot traffic, it's about any movement. I work with wood and it can be cut, shaved, shaped, but in the end, a sag in the board is a sag.

 

[PROSTOCKTOM]

Our family has been renting commercial and residential units since 1913, so I've grown up dealing with issues like this my entire life.

If it were one of ours we would tear it out and make it right. I am not in the business of having to deal with an issue 5 to 10 years later.

You can cut that iron pipe off down a few feet and use a fernco fitting to go from iron to plastic PVC pipe to replumb the toilet.

Yes, it's going to cost you some time and a few more dollars, but then it will done and you won't have to start all over again in a few more years.

Tom

 

[Triplegreen500]

I could try a screw jack post under the joist but I seriously doubt it will remove the curve. If it raises the low section, it's gonna raise the high section as well and my floor will still be uneven, just X inches further from the basement slab. And if it did un-curve, I'd be afraid of splitting/splintering from the process.

The floor is shaped like a skateboard deck - flat overall, with a kick up at the exterior wall end, which happens to be where the toilet is. A jack isn't going to un-bend that kick-up, not after 70-plus years of settlement.

The iron drain pipe is rock solid. If anything, it'll do 90% of the toilet support work. I just need a level floor around it so the toilet doesn't rock any and compromise the seal ring. And, I don't want the floor tile to crack either.

 

[zyzzyx]

 

[1967coronet]

View attachment 1801335View attachment 1801336

Crawl spaces, got to love em !
Looks good.

 

[1967coronet]

Been reading through this thread. Crazy but true we have the same venture ahead of us.
Guy in our rental house passed away .
Heart problem, 2 days in the hospital then gone. He was a good guy RIP,
Anyway he came with the place when we bought it 14yrs ago. Single guy , heavy smoker the damage was done in the house smoke wise so we just let it ride.
Always paid his rent early and didn't ask for anything.
But now here we go, pretty much a full redo , killz , paint , carpet, clean duct work, barrow a ozone machine, scrub and wash everything, new vinyl in the kitchen and bath. Same deal on the bath floor, it's all coming out to the joices. That's my advice as far as a fix on leveling things up.
His son emptied it out last week, I plugged in two glade air fresh things and ck the furnace. Just had my do over on the prostate surgery so I'm on a leash for a bit.
Scared to start on the house Lol.

 

[Triplegreen500]

Been reading through this thread. Crazy but true we have the same venture ahead of us.
Guy in our rental house passed away .
Heart problem, 2 days in the hospital then gone. He was a good guy RIP,
Anyway he came with the place when we bought it 14yrs ago. Single guy , heavy smoker the damage was done in the house smoke wise so we just let it ride.
Always paid his rent early and didn't ask for anything.
But now here we go, pretty much a full redo , killz , paint , carpet, clean duct work, barrow a ozone machine, scrub and wash everything, new vinyl in the kitchen and bath. Same deal on the bath floor, it's all coming out to the joices. That's my advice as far as a fix on leveling things up.
His son emptied it out last week, I plugged in two glade air fresh things and ck the furnace. Just had my do over on the prostate surgery so I'm on a leash for a bit.
Scared to start on the house Lol.

I wish you the best on the odors. I cut out the original hardwood floors and tossed it in the woods for kindling. That was....June? July? I could still smell the piss coming out of those boards in OCTOBER. Now that the hardwood is out; the drywall is out; the insulation is replaced and drywall is replaced (and I sprayed about a case of lysol into the HVAC ducting); it finally smells like a construction site and not dog and mouse piss. Just take it a step at a time, and give yourself reasonable goals so you don't get frustrated. If I'd paid a crew to do the drywall, it would have been done, mudded, and sanded in 2 days...but by doing it myself I save a ton of cash and I'm giving myself 2 weeks total. I'm a week in, and it's all hung except the bathroom (getting greenboard), which is waiting for me to figure out this flooring crap.

If you're adventurous, you can improve while you clean up. Since I had to strip it ALL anyway, I moved the kitchen from the back to the front (by the road) and moved a bedroom from the front to the back (nice and quiet). I also removed a center wall from the front so you walk in (center entrance) and the kitchen is to the right and living room to the left, nice and open and bright with lots of windows (two 4' windows in front and a 5' double window on each side). It's a great first impression as you walk in, if I do say so myself - and the bedroom is moved away from the noisy road. It also centralizes all the plumbing in one wall - the kitchen sink backs to the bathroom, and the tub and vanity are side by side on the bathroom side of the wall.

 

[RJ Squirrel]

You could use varying thicknesses of plywood strips about 4 inches wide, start at the deep end with 3/4, work your way back with 1/2, 3/8, 1/4, etc, then level it with fixall and glue down the new subfloor. I am with Tom on moving the toilet flange back, you can rent a cast pipe snapper to make short work of it.

 

[Triplegreen500]

moving the toilet flange back

Don't really need to move the flange. Can't move it too far back towards the wall as it is - it's 14" to the studs, which puts it close to a 12" rough in already. The flange looks like crap, but oatey makes a repair flange

so I can get my flange mount back.

Once I level the bad area to match the existing linoleum tile height in the rest of the bathroom, if I stack a 1/4" backerboard, a 1/2" backerboard, and a layer of ceramic tile with glue, it puts me just about dead-on the height of the flange. The flange may be 1/8 to 1/4" above the floor, but that should be just fine.

You could use varying thicknesses of plywood strips about 4 inches wide, start at the deep end with 3/4, work your way back with 1/2, 3/8, 1/4, etc, then level it with fixall and glue down the new subfloor.

That's the plan today, to set the level across the gap again and start figuring how wide a strip I need for each thickness of plywood. The net effect is a "thinner" floor at that end because the bottom is higher, but again, it's a zero-traffic area as far as walking goes, and between the cast iron and the immediate joist next to it, the toilet will have plenty of support.

The pipe isn't going anywhere, and it's level and at a proper height.