Tiling over a brick fireplace surround can give a whole new look to the room where the fireplace is located. After all, the fireplace and hearth are often the focal point, or gathering point, of the room for family and guests. While exposed brick is a classic look that can fit many styles, tile is much more adaptable. Glass tile, ceramic tile or stone tile can not only cover the brick, but complement the room's decor as well.
Mix the thinset according to the manufacturer's specifications, until it is the consistency of peanut butter. Spread the thinset over the bricks in an even coating, using the flat side of the trowel to smooth out lumps and ridges. The thinset will fill the spaces between the bricks and create a smooth surface for tile.
Allow the thinset to cure for 24 hours. Measure the fireplace surround to be tiled, in three places, the area across the top of the firebox and the areas of the two surround "legs." In an area of equal size, lay the tiles out in a dry layout. A dry layout consists of laying the tiles out without mortar to determine placement, cuts and grout lines. Locate the first tile in the centre at the bottom of the area directly above the firebox. Lay the next tiles equally out to the sides, as well as above. Next, lay the tile for the two legs.
Mark any tiles to be cut with the straight edge and pencil. Cut the tiles on a tile saw and return them to the dry layout to double-check the placement before tiling.
Spread a small amount of thinset over the area to be tiled, raking the grooved edge of the trowel over the thinset until the ridges are uniform in height. Lay the first tile in the centre directly above the firebox by pressing the tile into the thinset and then twisting it slightly into place. Lay the remaining tiles in the same way, in the pattern determined during the dry layout.
Allow the thinset to cure for 24 hours, and then grout the tiles by packing the joints with grout, using a grout float. Wipe up the excess grout with a damp sponge, taking care not to over wet or "wash" the grout, as this may cause the grout to lose colour. Allow the grout to set up for an additional 24 hours.