Subscribe or Renew Membership Subscribe Renew

is Gypcrete under a tub sufficient and what about the toilet flange?

2kathyg's picture


I'm having radiant heat installed on my concrete floor in my previously finished basement (which I am remodling currently and it is down to the studs). I understand that the tubing for the warm water will be covered with some depth of Gypcrete so this leads to three questions that I want to throw out to the crowd.

1) What is the minimun depth above the tubing that I should insist on?

2) I am also replacing the tub and toilet in the bathroom- should I block off the area the tub will sit and use something besides the finished Gypcrete to set the tub on?

3) Am I going to need to add new or raise the toilet flange and waste pipe?

I am having proffessionals do much of the work but I am acting as my own GC so I'm trying to ask all the right questions I can think of.

kathy (post #211574, reply #1 of 4)

The radiant contractor should dictate the margin of thickness necessary for the proper installation and operation of the system.

further, they will layout manifold location etc.

The finished ht. will tell the plumber the approximate ht. they need to rough their drains, supplies etc in order to install your fixtures and complete the job.  You'll need to supply them with finished floor material specs.

the tub drain and overflow area will be blocked out b/4 the pour to allow room to hook up the tub.  This will be both a screed and damn to keep the gypcrete to proper ht.  Set the tub on the gyp. at install.

the toilet likewise sits on the gypcrete.  The plumber can run his waste pipe up high at the toilet and cut down after the pour to install the flange.  When securing the flange its up to him how he likes to do it.  Some use tapcons (I would use length to get into the concrete) or by using anchors and screws.

so on this job, you are the coordinator relying on two others to work together and do it right.

best of luck.

A Great Place for Information, Comraderie, and a Sucker Punch.

Remodeling Contractor just outside the Glass City.


Calvin,  Thank you for your (post #211574, reply #2 of 4)


Thank you for your comments. I am appreciative of your insights!

You're welcome (post #211574, reply #4 of 4)

Would you care to continue with updates on your project?

It could be interesting and perhaps informative to someone else down the road.

you can keep it right here as a continuation if you like.



A Great Place for Information, Comraderie, and a Sucker Punch.

Remodeling Contractor just outside the Glass City.