Expansion in outdoor tiles

[Walter R.]

I am having a contractor tile my outdoor patio. It is partly covered and partly subject to rain and sun (Southern California, no freezing). The size is 11x 40 feet. Tile size is 18" square.

The tile will be installed on a concrete slab, using thinset. Should the contractor make some provision for heat expansion/contraction? Silicone grout? Control joints? He says, no provision for expansion is necessary.

Thanks

[barry]

Think about it for a couple seconds. Expansion _relative_to_ what_? And how much, proportionately? They're on masonry, remember, and both tiles and masonry are very conductive.

Concrete slab, though, will crack. And if such crack is under center of tile(s) I'd expect tile(s) to crack too, depending on the exact type and extent of deformation.

You hired an expert. I'd listen to him, and get assurances in writing.

HTH, J

[Don Phillipson]

If you suspect your chosen contractor is lying to you, why not consult the building permits office? If patio tile cracking required an expansion joint where you live, the probllem and its economic solution would be in the building code.

[Charles Schuler]

I'd check into the tile that he is going to use. Thermal expansion and contraction might be a non-issue.

[wrkg_onit]

For indoor spaces, over a cracked slab, a "membrane" is often used between the two to keep the tiles from also cracking. This may also be viable for outdoor spaces, you'll have to check.