I curious to now if anyone knows why the mortar bed for my 1917 tiled bathroom floor seems to be extra thick. I'm remodeling my first floor kitchen, which is under the second floor bathroom and have discovered that the bathroom plumbing seems to be laid into the mortar. This mortar bed seems to be about 2" thick. Is that to support the weight of the old claw foot tub? And more important...how do I replace that plumbing?