Waterproofing Subfloor Before Tiling

A tight unmoving bond between mortar and subfloor causes cracking.

Waterproofing subfloor before tiling.

It uncouples or releases the bond between plywood and tile mortar allowing each surface to move independently of each other. In addition uncoupling tile membranes prevent moisture from infiltrating surfaces below. If there are cracks larger than 1 8 inch in your concrete subfloor those should be patched and filled with a cement. Wear rubber gloves and safety glasses.

Next move on to coating the floor starting from a back corner and working your way outwards toward the door. Mix up a batch of mortar and spread it over the backerboard using the smooth side of the trowel. Cement is actually a very porous material and can easily absorb water. Press the waterproof membrane into the wet mortar on the wall.

Pourable self leveling products help to flatten and level a wood subfloor or a concrete slab before the tile is installed. Or you may store it outdoors under a tarp with blocks underneath the bottom sheet to keep it from touching the ground. Mix the leveler in a bucket according to the manufacturer s instructions. Waterproofing concrete is a fairly simple procedure.

Things change based upon the size of the room the use of the room the support underneath the floor the kind of subfloor the kind of tile adjacent flooring types etc. Use a paint roller or a sponge mop to apply the first coat of waterproofing sealer to the wall up to the line of masking tape. Apply wood sealants in a well ventilated area with doors and windows open. Concrete subfloors move shift and crack over time.

Once the entire wall is covered with mortar use the notched edge of the trowel to rake the mortar to an even ridged thickness. An uncoupling membrane does exactly what the name says. Seal the subfloor before adding your carpet or vinyl flooring to protect it from spills that seep through the carpet. Cut the end of the silicone caulk nozzle at a 45 degree angle using a utility knife.

The dry product is mixed with water to a liquid consistency and poured on. If cement is not waterproofed it can cause issues with the mortar used between the tiles. I like the books that taunton puts out tiling complete or working with tile. The membrane is waterproof not just water resistant.

It won t allow moisture from the subfloor to weaken the bond of the tiles to the floor. Apply the first coat of waterproofing sealer pour the waterproofing sealer into a paint tray. It s a huge topic and not something you can really cover in a single post. Therefore any concrete that may come into regular contact with water such as under tile or for a pool will need to be waterproofed.

It allows the tile layer to move independently of the subfloor so expansion and contraction caused by moisture and thermal gradients won t cause the grout or tiles to crack.