Latest Frequently Asked Questions
Can you place roofing paper (tar paper) under the shower pan liner instead of concrete?
You cannot use any tar paper when installing the shower pan liner because the
petroleum in the tar paper will dry the liner, and the liner will become brittle and crack if there is prolonged exposure.
Can you install the pan liner when the floor has radiant heat?
Yes. Only CPE liner is approved for this application because of its ability to withstand
high heat.
Can I use pipe solvent cement to solvent weld shower pan liner together?
No. The formulas are very different and cannot be interchanged.
What type of concrete do I use when I install the shower pan liner?
The approved products for this application are bagged Portland Sand mix, or cement
mix for the base and top coatings. If you are going to mix and match, you must use Portland sand mix under the liner.
What is an approved caulk to use between the liner and shower drain flange?
Oatey 100% silicone caulk. If Oatey product is not available at your retailer, any brand of 100% silicone caulk.
How do I install the outside corners (dam corners)?
The outside corners are PVC material, and you will cement them to PVC and CPE liners
with X-15 cement only.
How do I fold the inside corners when installing the liner?
Once the liner is pushed tightly into an inside corner, there will be a triangular section
left over. The first step will be to cement the inside of this triangular piece to itself creating a flap. The second step is to then choose a direction right or left and cement the flap to the liner on the straight wall, then nail / staple top of flap to a stud.
Can I glue the liner to the wood sub-floor?
No.
How high above the drain should I end the liner?
The drain is not the determining factor for finished pan height. The curb (threshold) is the determining factor of this application since it always above the finished height of the drain. The pan liner should finish a minimum of 6 inches above the framed or (roughed-in) curb height. This height allows for the application of concrete base and finishes to be applied.
How do I seam two pieces of liner together?
Once you have the two pieces of liner cut square and laid flat on a warm hard surface (above 50°F), you must overlap one of the pieces over the other at least 2”. If you are seaming PVC liner use Oatey X-15, if the liner is CPE you will use Oateyweld. Fold back the top piece of liner and wipe any debris or foreign substance off both surfaces with a damp cloth and then dry thoroughly. Apply the proper cement for the application to both surfaces allow 1 to 3 minutes in hot weather and 6 to 8 minutes in cold weather, then join then together. Immediately apply pressure on the seam for 15 to 30 seconds with a 2x4 or equivalent. Leave this seam cure for 12 hours before installing, but after one hour there is good handling strength and you can move the liner.
Can I install tile on top of liner without concrete?
No. Thinset or tile glue (adhesive) should never be applied directly to the shower pan liner.
How thick should I pour concrete on top of liner?
The recommended thickness for this pour is between 2” to 3”. This is the minimal thickness starting at the drain, then sloping up and away from the drain at a ¼” per foot. This is not always possible due to curb heights. If this is true, pour as thick as possible and consider a higher quality cement which will allow for a thinner pour while maintaining strength.