New shower
I am in the process of building a new shower in my remodeled bathroom. I have always used the Oatey pan system in my previous builds but want to use the more modern approach. The shower is 3'-6" x 5'. The sub-structure is concrete that is pretty rough. My plan is to:
-install FlowFX drain approx. 1-1/4" above concrete foundation.
-use modified thinset over the concrete foundation to help Mudbed adhere.
-while wet, lay dry packed Mudbed sloped 1/4" per foot to the drain.
Now my options are:
install Kerdi membrane on floor and partially up the walls or
use Hydroban on floor, corners and walls or
a combination of the two.
If I use the Kerdi, what adhesive is recommended?
I know I have to wait at least 10 days to use the Hydroban over fresh drypack, but how soon can I install the Kerdi?
Any advice will be helpful.
Laticrete says 3 days. But in all of my testing it was at least 6 before all the moisture was out of the bed. Depends on temp and humidity but if you have the time, longer is better. There is no issue with adhesion, or long term performance but if you water test before the moisture is less than about 5% in the mud bed, bubbles will form as the moisture tries to escape the mud bed through the Hydro Ban.
The moisture will continue to evaporate through the Hydroban until it is gone believe it or not. Hydro Ban is not vapor proof. But if an 1" water is on top of it from a flood test too early that's when there can be issues.
I wouldn't worry in your case because from the time you installed the Hydro Ban till it was finished and used was more than enough time for the moisture to evaporate out of the mud bed.