How to Lay Natural Slate Tiles Over Slab Cracks
- 1). Coat the entire surface of the slab with an antifracture paint-on solution for slabs with generalized spiderweb cracks. Roll the paint onto the slab with a paint roller, and use a paintbrush to coat the inside corners sufficiently. The exact coverage will depend on the type of product you purchase. Always let the paint solution dry sufficiently before installation. This is usually 24 hours, or dependent on the manufacturer's specifications.
- 2). Cover specific areas of spider-webbing with antifracture mesh and paint. If your slab only has small, specific areas where the spider-webbing has occurred, you only need to patch the areas where things could potentially spiral out over the years. Cut the fabric with a razor knife, and paint the floor with the liquid solution, using a paintbrush. Install the fabric and coat it again. Let it dry before installing the slate tile.
- 3). Protect the area over expansion joints with an antifracture fabric. These are thin layers of fabric coated with a layer of tar and adhesive on the backside. Clean the floor around the expansion joint, and peel back the protective layer on the fabric to adhere the fabric to the floor. Keep it tight and without air bubbles. Cover the expansion joint at least 6 inches on either side, and carry the joint up through the slate installation so the joint on top of the expansion joint is a caulk joint, not a grout joint.
- 4). Install an antifracture membrane for complete protection against all types of cracks and joints. Cut the membrane to fit with a razor knife, and install it with a thin layer of thin-set mortar underneath the mat, between it and the concrete. Let the mat dry for 24 hours before you install slate tile over it.
- 5). Install the slate tile floor as you would normally install any tile. Lay out your floor, and spread the thin-set mortar on top of the antifracture membrane solution that was your personal preference. Install the slate tile into the bed of thin-set, and grout the installation after it is finished for a completed project.
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