Hello everyone - this is my first post. I am installing a custom shower and using Hardie Backer Board over a rubber liner. The liner extends over a shower seat - that will be exposed to direct water flow. I have sloped the 3/4 plywood and covered it with rubber shower pan. What is the best way for me to attach the backer board to the rubber pan? I am concerned about using screws, as I don't want any leaks. I plan on putting a piece of granite over the Hardie Backer board.

On 3/19/2014 7:26 AM, Pappy wrote:
Hello everyone - this is my first post. I am installing a custom shower
and using Hardie Backer Board over a rubber liner. The liner extends
over a shower seat - that will be exposed to direct water flow. I have
sloped the 3/4 plywood and covered it with rubber shower pan. What is
the best way for me to attach the backer board to the rubber pan? I am
concerned about using screws, as I don't want any leaks. I plan on
putting a piece of granite over the Hardie Backer board.

Never done this sort of install but...

Were I you, I would first seal the seams/edges of the rubber pan affixed
to the ply with silicone adhesive/sealant. Next, when you fit the
Hardie board, pre-drill the backer board, set in place, and then "prick"
the rubber to mark your holes. Put a quarter dollar sized dollop of
silicone at the prick marks and lay the Hardie in place. Place another
dollop of silicone over the holes and screw it down.

If THAT leaks through... sell the house for you have been doomed by the
fatesg

Seriously, I'm thinking we're both going way overboard on this.
Seamless rubber membrane, properly installed, covered by Hardie board
and then with thin set, and granite. Depending on the size of the
granite pieces and quality/composition of the grout, location of the
screws, etc. it seems like it will be pretty resistive to water
migrating in.

Pappy wrote:
Hello everyone - this is my first post. I am installing a custom
shower and using Hardie Backer Board over a rubber liner. The liner
extends over a shower seat - that will be exposed to direct water
flow. I have sloped the 3/4 plywood and covered it with rubber
shower pan. What is the best way for me to attach the backer board
to the rubber pan? I am concerned about using screws, as I don't
want any leaks. I plan on putting a piece of granite over the Hardie
Backer board.

I'd seriously consider using a coating on the water side of the whole thing,
like Redgard or Kerdi.

There are special adhesives for the shower pan material. Maybe one of them could
be used to attach the hardie board, or could thinset be used to attach it.

On 3/19/2014 11:38 AM, Bob F wrote:
Pappy wrote:
Hello everyone - this is my first post. I am installing a custom
shower and using Hardie Backer Board over a rubber liner. The liner
extends over a shower seat - that will be exposed to direct water
flow. I have sloped the 3/4 plywood and covered it with rubber
shower pan. What is the best way for me to attach the backer board
to the rubber pan? I am concerned about using screws, as I don't
want any leaks. I plan on putting a piece of granite over the Hardie
Backer board.

I'd seriously consider using a coating on the water side of the whole thing,
like Redgard or Kerdi.

There are special adhesives for the shower pan material. Maybe one of them could
be used to attach the hardie board, or could thinset be used to attach it.



You probably are already aware that epoxy grout is going to be much
better in the shower also. That helps keep the water from ever getting
to the membrane. And don't for get to put in the bracing for the shower
bars too. You want them to be in something very solid. I put a 2 x 6
face out between the studs.