Tommy Mac Discussions › Forums › Fix-it Forum: Home Improvement & Do It Yourself Repair Forum › Laying wonder board over luan
Can I lay Wonder Board over luan if I do not use mortar between the two? We have already installed our shower over the luan, and it would be impossible to remove the luan from the floor at this point.
install the wonderboard over the existing lauan, even with a thinset mortar.
However I think the best solution is to remove the lauan up to the shower, the wonderboard and tile will more than cover the height difference, so that you don’t have to worry about a gap showing.