What a great way to seal your Duroc before tiling! I used a brush, but I highly recommend getting a disposable applicator roller. You can use a brush to fill holes between layers. This one bucket was enough for my entire two coat shower stall. My environment is about 65 square meters after counting the two alcoves I built. I also have a 30" x 42" window in the long wall that I subtracted. The first layer took up most of the container, but it was still enough to finish the job.