How to Lay Tile Floor for a Screened Porch

Laying tiles on a screened porch is similar to installing them indoors, but a little extra preparation is necessary, along with some special materials. The most important issue is temperature variation, which causes most tiling, substrate and mortar materials to expand and contract. This can cause the tiles to crack. Laying specialized tiling membrane under the tile will help blunt the effects of temperature changes. Use outdoor-rated grout and tiles.

Things You'll Need

• Flat trowel
• Tile mortar
• Tiling membrane
• Utility knife
• Tape measure
• Chalk snapline
• Carpenter's square
• Notched trowel
• Tile spacers
• Wet saw
• Grout with latex additive (rated for outdoor use)
• Grout trowel
• Sponge

Instructions

1. Spread tiling mortar on your concrete floor with a flat trowel, making it about 1/8 inch thick. Roll out tiling membrane over the mortar as you spread it, pressing down the surface of the membrane with the trowel as you go. Cut the membrane at the ends to fit against the walls. Cover the whole floor.

2. Divide the area into four equal sections, using a chalk snapline to make lines from mid-wall to mid-wall in both directions. Square the lines against each other, using a carpenter's square.

3. Spread down tile mortar with your notched trowel over the membrane, starting at the center of the intersection and laying a few square feet of mortar at a time. Press the first tiles into place at the intersection, putting tile spacers between them.

4. Build out toward the walls, along the lines, cutting the end tiles as needed on your tile cutter. Let them set overnight.

5. Remove the spacers. Grout the floor with your rubber grout trowel, forcing the grout into the spaces between the tiles and squeezing it off the face. Wipe off the excess grout with a damp sponge.

Tips & Warnings

• If the floor is wood and not concrete, lay a layer of 1/2-inch cement board over the wood, securing with mortar and galvanized screws, then proceed as before, putting the tiling membrane directly over the cement board.

• Wear eye protection when cutting your tiles.

References

• Schulter.com: Using Tiling Membrane.