I have a covered patio attache to the house. Concrete slab that I want to overlay with either creamic or Mexican clay tile. Currently the Patio sweats in when there is temp flustuatio durringthe winter months (deep South). How should prep the surface before layingthetile o there won't be bonding problem or problems with the tile sweating. I've though f overlaying the slab with visquene then laying down thin concrete backerboard but am concerned that there would then be no bonding to the subsurface.

I don't know about laying exterior tiles, but a word of caution about Mexican tiles. Be sure they're sealed before you lay them, otherwise you'll never get the cement off them. I used them indoors and wasn't terribly thrilled. When the weather was humid they smelled like urine. Weird.

Good to know. The more I hear the more I'm inclined to go with ceramic tiles that look like Mexican Clay tiles!
Still looking for the answer to my question regarding the sweating slab.

Outdoor tiles should be frostproof. Porcelain or quarry tile are frostproof. Regular ceramic tiles are not frostproof. Unglazed Mexican tiles will require sealing and maintenance. After grout has cured, grout should be sealed. Follow label directions for application and number of coats and frequency of resealing. Grout is porous and absorbent and absorbs soils, oils, and stains.

Concrete must be very, very clean and free of all contaminants such as paint, sealers, oils, soils, or anything that would interfere with the bonding with the exterior rated thinset. Concrete underlayment is not installed over concrete!

If you DIY, you want to do everything correctly so that you will have a successful installation. A reputable tile dealer should be able to provide you will all the info and products you need.

This message has been edited. Last edited by: twelvepole,