Securing Closet Flange

[rms]

I am replacing an existing toilet flange was not secured. There was a coffee can filled with dirt surrounding the soil pipe, so there is nothing to secure the new closet flange to. I am installing wood laminate over a concrete slab. The only solution I can come up with is to dig out the dirt and slap some concrete patch in, then secure it with tap cons. Any other suggestions?

 

[Plumber1]

Cast iron or PVC?

 

[Sponsor]

 

[Mikey]

I think you're going to want to do the concrete thing anyway, to prevent (or at least inhibit) moisture from the earth below working its way up to the floor. Even with the patch, be sure the moisture barrier required under the laminate is well-sealed around the flange.

 

[rms]

It's PVC. I forgot to add that my wife, "the plumber wanabe", dug out some of the dirt and filled it with foam insulation. so I have to remove that first. Also, thanks for the moisture clue. That probably explains why the existing vinyl flooring discolored under parts of the bathroom (concrete slab).

I know i'm going to get flack for this but since no one in the house is over 160 lbs., could i put 4 toggle bolts under the laminate to hold the flange and between that, the soil pipe connection and the caulking around the base, would it be enough to hold?

 

[Prashster]

I wouldn't use toggle bolts. The laminate can still shift over time which can compromise the toilet seal. If yr gonna do that, then you should first tapcon those pieces of laminate to the concrete; i.e., don't let that section 'float'.

As far as the vapor barrier goes, concrete doesn't stop moisture or vapor. Polyethylene does. You need a moisture barrier UNDER yr slab. I'd first excavate all the insulation and dirt from around the pipe, then cut a 3" hole in 9mm or better pe and thread the toilet flange with it. Then 'crete on top of that - for stability and support, not for vapor prevention.

You also want to know whether the rest of yr slab has a vb under it. If yes, then don't put another one on top of the slab. Moisture has to have a place to go - trapping's a nono.

If yr having staining probs, you might consider putting in Subflor or Dricore. They're fairly cheap T&G OSB panels that ride on corrugated plastic channels. The channels protect the floor from moisture and even minor flooding. It's perfect for laminate, since the panels are floating also. However, around yr toilet, you should tapcon the panels into the 'crete and then screw yr flange to the panels. I Subflor'd my basement bathroom and I love it. Really warm.

 

[Kordts]

I would fill it with with quikkrete and then tapcon it.

Normally 1-1/4" on these.

 

[Gary Swart]

Another way to anchor into the Quickcrete is with lead ferrels and stainless steel screws. Ferrels are my personal preference for anchoring anything into concrete, and of course stainless steel around the toilet flange just makes good sense.

 

[rms]

thanks for all the tips. this is a great site.