A Poorly Designed Kerdi Linear Trench Drain
You need to be careful how you proceed and what products you choose to build your new shower. Here in Vancouver I just visited a job site in a Luxury Hotel's Private Residence that had a Schluter Systems Kerdi linear trench drain. I have seen many showers built this way online from a number of different designers and from numerous locations around the world.
It wasn't until yesterday that I had seen one first hand.
The shower was nasty. The most beautiful Carrera Marble was used and the plumbing package was "Top Shelf" - Schluter, Dornbracht and Kohler together in one shower unit.
The shower was built with a raised sloped platform that ran into a tiled trench drain. The trench was linear in design and a Schluter or Kerdi Drain used for drainage.
The amount of "Orange Mold" was crazy. Take a look at this install. Would you be happy with this shower after only 12 months of use?
This picture I took with my camera on the short wall looking down.
This picture taken with my camera in the trench looking back towards the raised platform.
The silicone here in this picture I think is slowing the weeping of the raised shower platform. Required in all change of planes - if you follow all the rules. A horrible design. A proper linear drain would work much better.
Puzzling how a ABS drain was used in a commercial project.
Not sure how an ABS drain was used in this shower. ABS is not yet fire rated in BC to my knowledge and is not allowed in commercial projects. This is clearly an ABS drain and the drain most likely has had one end bent up to allow this style of shower to be built. I have spoken with Schluter's tech support and have been informed in the past that they have no such bent drain nor do they advise anyone to bend one.
The plastic in the drain just under the stainless grill puzzles me. I wonder what purpose this serves in the drain assembly. I wonder if this plastic is slowing the weep rate into the drain???
As most people know Schluter requires non-modifed thinset to install their tile over Kerdi. Many marble suppliers will suggest the use of modified thinsets. Round and round you go. What do you do?
What went wrong here? Why is the mold Orange in colour like the Kerdi membrane?
Perhaps the type of soap or shampoo used?
Perhaps standing water and no pre-slope?
Perhaps some mineral reaction with our local water?
Perhaps a lack of ventilation?
This is just one shower in a Luxury Hotel. I plan on looking deeper into the problem - I see the potential for a lot of shower pan repairs in the horizon.
Check your crews references. Check yourself that all the products spec'd for your new shower's construction work together. Use better setting materials - many of today's top setting materials have additives designed to stop mold growth. If this means you can't use Kerdi - then don't use Kerdi. Use Nobel, Use Hydro Ban, Use Aqua Defense, Use Durval.
Building a shower and designing a linear trench drain is more than slapping some mortar on the floor and making a trench. You need to understand how the end product will work before you even start.
If you can step back and forget the mold in these pictures. This style of construction if properly built would allow you to add River Rock and fill the trench with stone. A very popular look lately. This design better served I think with a different drain and more thought to drainage to the weep holes.
The link above will show you an example of a River Rock Trench.
When researching shower construction look into "Candle Wick" & "Hemp Cord". Do you understand what these products can do for your drainage? Find out...
(604) 506 6792