tcna handbook for ceramic tile installation detail ej171

Your waterproof membrane should be going up the wall at least 6” as you know they normally use water hoses to wash down the tile during cleaning at the end of the night. But since this is a commercial kitchen, then I would fill all perimeter joints with the ASTM C920 sealant (silicone or polyurethane) as a water stop to help prevent water getting inside the walls. Normally if you have a shoe base then you can leave the movement joints open and place the base over it so you can’t see it. You need to have movement joints that are ¼” wide at all perimeters of the tile areas and where it changes plane. Movement joints on interior applications should be installed every 20 to 25 feet in each direction. The sealant should be tooled to a slight concave finish so that foot traffic does not come into contact with it to prevent it from getting excessively dirty. The sealant needs to be up to ½” thick and at least ¼” thick.

A closed cell compressible back up strip is inserted with an ASTM C920 Traffic grade sealant installed over it. The membrane then needs to be looped into the movement joints to be continuous. If you are floating a mortar bed over the substrate to establish a slope to drain for the waterproof membrane to go over and for the tile to bond directly to the membrane, then the movement joints need to be continuous from the structural slab up through the tile. Otherwise you need to install the backup strip with the ASTM C920 sealant over it.Įxpansion joints is a type of a movement joint as described in TCNA Handbook detail EJ171. It can be left open if there is a tile base going over it.

Exterior and Interior applications subject to direct sunlight are to be placed every 8 to 12 feet in each direction.īe sure to include movement joints at all the perimeters, change of plans, and where you are tiling up to restraining surfaces. They should be installed very 20 to 25 feet in each direction for interior applications that are not subject to direct sunlight. It should be tooled to achieve a slight recess so the foot traffic doesn’t touch the sealant. The joints are suppose to have a compressible closed cell back up strip with an ASTM C920 Traffic Grade sealant. It is not uncommon for the movement joints go straight across, which would be more practical if the movement joint extends into the mortar bed if this is a mortar bed installation. The TCNA EJ171 now allows for zipper or sawtooth generic movement joints in tile installations, where you follow the grout joints within the tile assembly, not into the mortar bed.

Tcna handbook for ceramic tile installation detail ej171