Suggestions on what to fill a crack / hole with for waterproofing?

[e9999]

so I have this pipe in the floor of my second story bathroom. This is the drain for the toilet. The double wax gasket leaked and water seeped in under the floor. I am fixing this and I want to fill the holes and gap around the drain pipe going down in the floor. I can't quite see what the condition of the wood is under there but I am not going to rip it open just now. I just want to fill the holes and gaps so that if there is another leak it will not go directly in the floor. I need to identify some material that will readily flow perhaps as much as 2 or 3 inches deep in a narrow crack / gap (say 1/8" or so) or cap it well. The opening is not directly accessible, so I'll have to pour it nearby and have it flow hidden in the gap. I'd rather it not be something very hard like epoxy in case I have to dig in sometime later. Also it would be better if it were not nastily staining stuff since it could well go down to the ceiling below.

Caulk is not flowy enough to fill all the passages and gaps I think.

Possibly I can use a can of this expanding foam stuff if the spout is flexible enough to reach under the flange and if it's waterproof enough. This may not go deep but if fills the top and makes a good seal that might work.

I could also pour paint I guess, that might go deep in.

Polyurethane glue maybe after wetting everything?

Some sort of liquidy mortar or grout?

Ideas?

TIA

 

[hydrogeo]

Not an expert by any means but could you stuff some fiberglass insulation or some other filler material into the hole to help prevent whatever you pour in from ending up on the ceiling below and then use a mortar-type floor leveling compound. I have used this stuff before to level concrete floors before putting down tile and it flows well and sets up water tight as long as it doesn't crack. In then end you are probably better off fixing the floor.

 

[Cookiemonster]

Thing to do is bring the pipe drain ring up flush where you want it then use some "Good Stuff" polyethlene expandable foam (red & yellow cans) and shoot it in. It will not only fill in any voids but it will harden up and give some support to piping or potentially damaged soaked wood.

Don't worry if it expands to much. Let it dry and cut it flush or wipe it down as it is expanding (more like warm taffy when not set yet).

All of this is fairly easy to remove later when your ready to remodel down the road.

 

[e9999]

Thing to do is bring the pipe drain ring up flush where you want it then use some "Good Stuff" polyethlene expandable foam (red & yellow cans) and shoot it in. It will not only fill in any voids but it will harden up and give some support to piping or potentially damaged soaked wood.

Don't worry if it expands to much. Let it dry and cut it flush or wipe it down as it is expanding (more like warm taffy when not set yet).

All of this is fairly easy to remove later when your ready to remodel down the road.

this is waterproof foam when set?

 

[Toyo FJ40]

this is waterproof foam when set?

Great stuff is waterproof

 

[e9999]

I did try a polyurethane foam, don't recall brand. Need to do a test to see if waterproof or not.

 

[webelk6]

I have seen plumbers melt lead(with water nearby) into "gaps" . Once it solidifies you are golden.

 

[e9999]

I have seen plumbers melt lead(with water nearby) into "gaps" . Once it solidifies you are golden.

well, that's what they did on the main flange, apparently. I sure don't want to do that cuz it's a pain to remove anything. Plus dripping molten lead in a crack that goes you don't know where with wood and insulation seems a bit unsafe to me.

 

[webelk6]

How high is your main drain for the toilet? How does the toilet seat when you smash it down on the wax rings? Sometimes floors are added on, and lowers the main drain creating a gap. I would hate to see you have to rip out that floor and start from scratch.

 

[e9999]

How high is your main drain for the toilet? How does the toilet seat when you smash it down on the wax rings? Sometimes floors are added on, and lowers the main drain creating a gap. I would hate to see you have to rip out that floor and start from scratch.

I think it was just put in improperly when new with the current floors on.
It should be fine with the foam I think. A little test suggested it may indeed be reasonably water proof.

 

[Toyo FJ40]

I have seen plumbers melt lead(with water nearby) into "gaps" . Once it solidifies you are golden.

I'm a plumber and I do lead joints all the time but never against wood. If there is any mosture in the area the lead will blow back in your face.
There are repair plates that cover the area under the toilet and screw to the floor. Like this one.

Floor repair plate


Kevin

 

[badmuthatrucka]

I worked in construction for a few years, and have seen a lot of problems like this. Until you are ready to redo the floor, the expansion foam is probably your best bet. See if you can get a smaller diameter, more flexible hose to fit inside the hose it comes with. Push that down as far as you can and start filling. You might need to insert in one area, spray some in, remove hose from floor. Reinsert an inch or so away, and repeat until hole is filled. It sounds like Toyo FJ40 knows his stuff a lot better than I do, so if what I just said makes no sense, follows what he says.