Find the center line on the mantel and, after buttering the tile backs with thinset, set them from the center out. Symmetry is what's important,' Whitehead says. Lay the hearth first, then cover it with a plywood platform. Install the tile over the firebox opening next, then the sides. Allow the thinset to dry for at least 24 hours before grouting.
Caulk is flexible enough to accommodate the different rates of expansion of the two materials.
Plan on two days' work if you tile the mantel yourself. Her partner, Terence Mulligan, created an exotic wood mantel with a faux-finishing technique. Mask off the adjacent walls and keep a damp sponge handy to wipe up. Use a separate brush for each color and dab both on at the same time. Work in tight, controlled movements.