These cracks may eventually show up in tile or dressing applied before the 28 day curing period.
Concrete slab preparation for tile.
Let the primer dry and then apply the membrane photos 3 and 4.
Some also keep water out of the installation area.
How to pour a concrete slab.
Don t lay tiles on a concrete slab with cracks that appear to be spreading or irregularities that prevent you from leveling it.
Masons often use a crack isolation membrane when setting tile outdoors.
To prepare your concrete subfloor make sure that it can accept water penetration.
Test by sprinkling water on various areas of the subfloor.
Cut the membrane so it s 1 1 2 times the width of your tiles.
Ideally you want a rh of about 75 to 80.
New concrete must cure a minimum of 28 days before either tiling or putting a dressing onto the new concrete.
1 as the concrete cures drying and shrinkage cracks could occur.
A sound surface is necessary when preparing concrete floor for tile installation.
With the cracks patched apply a latex modified crack resistant thin set.
Crack isolation membranes keep imperfections in the concrete slab from spreading up to the tile.
Then figure on spending a day building the forms and another pouring the slab.
No matter how dirty or clean the concrete floor looks start the process by sweeping the floor.
There are two reasons for this.
The basics the bulk of the work for a new slab is in the excavation and form building.
How to prepare concrete for a tile installation 1.
If you have to level a sloped site or bring in a lot of fill hire an excavator for a day to help prepare the site.
Patch little cracks or holes with a cement patching compound.
Use a trowel to apply and use the edge to ensure the patch has edges level with the surrounding concrete.
Additionally a steps must be taken to ensure that a concrete floor will create a solid bond.
There are epoxy coating systems for applying a vapor retardant over the concrete slab surface before you tile over it.
There are different kinds to choose from.
The substrate for tiles shorter than 15 inches must be so flat that it varies no more than 1 16 inch per foot according to the ceramic tile education foundation.
Then prime the concrete see photo 2 with the recommended solution consult the membrane manufacturer s literature.
It mitigates extreme moisture conditions.
As with a wooden subfloor a concrete subfloor must be level for successful tile installation.