My wife and I are going with a Drolet Escape 1800 stove which is a pedestal style stove. We're going to do a corner install. The manufacturer states that only a noncombustible surface is needed under it, no specific R-rating material with how the stove is designed. We're planning on doing cement bored with tile. My wife wants to use slate. I like it but I'm worried about the unevenness of slate with a pedestal stove. Do any of you have experiences/input on this? The slate we're looking at is 16X16" and the pedestal is 22X17.