Shower pan membrane height

[james.f]

Hi folks, it's late now, but I'm just checking on the requirements for a shower pan membrane. As shown in the attached picture, there are screw holes along the bottom of the cement board that go through the shower pan membrane (it was very tall, about 12-14 inches). A few things:

• The lowest screw is above about 7 inches of membrane, all the others, around 8.
• The curb is quite tall, and there is an inch of mortar on top of it, meaning the lowest screw is about 1 inch above the curb, or about 2 inches above the curb's membrane, others 2 and 3 inches respectively.
• The lower sheets of cement board have about 1/4 - 1/2 gap along the bottom
• The boards will all be covered with redgard, and the bottom gap will be caulked, hopefully preventing any water wicking.
• There is a preslope under the membrane and blocking around the sides. Floor drains very well/weep holes work.

Is there a concern for moisture issues, or concerns that may be brought up during inspection regarding this? I mistakenly thought it was "2 inches above drain height or at curb level" and thought this was more than enough, but triple checking has me concerned.

Thanks,
James

 

[Jadnashua]

It's up to 2" above the top of the curb where no fasteners are allowed, however high that is. The 2" above the drain is for the curb height minimum. Check out www.johnbridge.com