Frequently Asked Questions
What goes under tile — in what order?
Structure first: a flat substrate (leveler if needed), then board or membrane (backer board, uncoupling, crack isolation, or sound control as the job requires), then thinset and tile. Wet areas add waterproofing before the tile layer.
Do I need underlayment over concrete?
Often yes: an uncoupling or crack-isolation membrane protects tile from slab cracks, a leveler fixes flatness, and condos may require a sound membrane. Bare, flat, crack-free slabs can be tiled directly.
Which backer board is best for a shower?
Foam boards (GoBoard, Kerdi-Board) are waterproof as installed and light to handle; cement board works too but needs a waterproofing layer over it. Either way, treat every seam and fastener.