ORC Week 4: Waterproofing and Tile Layout
It’s the last day of week 4 and writing this blog two hours before it’s due because it has been a nightmare of a week for our master bathroom reno. Last week we talked about how we installed the Schluter system to waterproof our shower floor and walls. During the installation process we noticed that the thin-set we used to install the Schluter system was not drying properly and when it did dry, it did not bond well to our Schluter system. This was very concerning to us because if the Schluter system is not properly bonded to the drywall, it will cause leaks when we start using the shower. Consequently, leaks behind the wall tile could cause mold and rot out the joists, and flood our first floor. There is a lot of risk in this phase of the project so the Schluter company sent out one of their representatives to confirm what we had known was true.
The thin-set we used turned out to not have enough bonding power to holder the Schluter system in place. Before installing the Schluter system with the unmodified thin set we contacted Schluter to confirm that the thin set we were using would work and is compatible with their product. We got a confirmation from their customer support but unfortunately, that turned out to not be true. We lucked out but double-checking with Schluter professionals and their representative was kind enough to give us a new system to install.
Having to remove the old Schluter system, could have caused damage to our drywall and plumbing but we were able to remove everything without any issues because the thin-set was weak and the Schluter membrane just peeled off. The hardest part of removing the membrane was having to sand off the thin-set from the drywall which took a ton of work. The lesson learned here is this: if you are going to install a Schluter Kerdy membrane to waterproof your shower walls and flooring, do not rely on any brand of thin-set, even if approved by Schluter customer support. Go ahead and save yourself a bunch of headache and time and use their thin-set.
While the whole ordeal around having to redo the waterproofing for the bathroom put us a week behind, we were still able to install cement boards on the entire bathroom floor. Cement boards provide an underlayment for the floor tile which we plan on installing next week. Before installing floor tile it is always a good idea to do a layout and perform pre-cuts. We ran out of time this week to do pre-cuts but we did do a layout of the floor tile and have a good understanding of how many tiles we will be installing and which ones we need to cut.
We used a chalk line reel to do a layout which is basically a grid on the floor outlining where tiles will be installed. The chalk line reel is extremely helpful because it allows you draw straight lines on relatively flat surfaces, much farther than is practical by hand or with a straightedge. They may be used to layout straight lines between two points, or vertical lines by using the weight of the line reel as a plumb line.
The tile we will be installing is this black and white checkered tile that we plan on installing going diagonally. I think the diagonal layout or harlequin style is truly classic (left image) and while it will cause more waste because more cuts are required, I think it will be worth the extra effort.
harlequin style 
checkered square style
Thank you for following along this week and cheering us on. We received a ton of messages on Instagram from people who has experienced the same issue with their Schluter membrane installation and we appreciated all of your suggestions and ideas. In times like these when not everything is going to be plan, it’s great to have a community to support and encourage us along the way.
We are extremely excited to start tiling the floor next week so stop by on our Instagram if you are interested in the daily detailed updates of our installation progress. Check out other One Room Challenge participants’ progress here.
