aqua defense over mud pan

I have just had a mud pan over vinyl shower pan liner installed. My question is can I put AquaDefense on top of the mud under the tile? Will this cause some kind of problem. I want the shower to be water proof and also plan to do the joints and walls.
Thanks in advance for any hel

First, if the liner is flat on the floor without a preslope underneath it, it is not installed properly and you should start over! THen, multiple waterproofing layers is never a good idea. The waterproofing layer MUST be sloped to the drain, and that is NOT the tile. Depending on the type of drain you use, something like a clamping drain, which is probably what you have in there now, is not compatible with a surface waterproofing layer. There is definitely more than one way to produce a leak free shower, but it doesn't sound like yours got started out properly for any of them.

Waterproof and vapor proof are not the same thing. You can be one without being the other (think Gortex). I would not want two surfaces with that absorbent layer of deckmud in between. My personal opinion.

Johnfrwhipple,

I noticed in one of your other posts you said...

"Using a liquid membrane over a fresh mortar bed can be tricky. Unless you have access to a rapid setting mortar like Mapei's Mapecem Screed Mortar Fast Setting you need to wait while the mud bed cures and most of the moisture has left the install. With a traditional 4-1 mix that can be 4 weeks. With a product like Latecrete's 3701 you can Hydro Ban over top in 72 hours and with Mapei's Mapecem Fast Setting Screed Mortar as fast as 24 hours"

I can get the Latecrete 3701... So if I use it and wait the 72 hours before using a product like Hydro Ban on top of the mud pan will it cause a problem? The previous shower leaked and I would like to be extra sure there won't be a leak this time.