Sealing Terracotta Tiles?
We have a house with terracotta tiles on the exterior that are beginning to crack from exposure to the elements. They are new, done by the developer, but we think that they weren’t properly sealed or finished for the weather in the NE. We see plenty of historic buildings with terracotta that look just fine…
We have a house with terracotta tiles on the exterior that are beginning to crack from exposure to the elements. They are new, done by the developer, but we think that they weren’t properly sealed or finished for the weather in the NE. We see plenty of historic buildings with terracotta that look just fine and are way older than ours. Any suggestions on what should be applied to preserve them? Any recommendations on someone to do it?
Thanks!
Yes, if the tiles were meant for indoor use or an environment with less moisture and freeze/thaw, you will see failure almost immediately. An unglazed terra cotta tile is probably not the best material for outdoor use in the northeast. (Most red-colored architectural terra cotta has a slip glaze and is not a thin tile, which is why it can stand the environment.)
It may just be that the tiles you purchased aren’t able to handle the freezing temps and humidity in this region. The tiles you see on other buildings in the area are much older and weren’t made by artisans in the southwestern US. Could be dependent on the type of clay used, the temperature they are fired at, etc. Probably going to have to talk to the tilemaker.
Sorry, I should have been clearer in my posting — they’re artistic/decorative tiles, not flat ones. If they do have a glaze, it’s not apparent. They were handmade by an artist in NM or AZ. We can contact the developer to find out…
You should find out what kind of terra cotta tiles they are and how they should be installed. Glazed terra cotta comes that way from the factory, so as codeconfused says, it may be a manufacturing defect (though improper installation can’t be ruled out).
Glaze failure on older terra cotta is usually the result of water infiltration, which results in crazing and spalling. The real dramatic failure comes when the iron cramps holding the terra cotta onto the building start to corrode, which results in unit fracture or failure of the whole unit (it just falls out). Iron and (non-stainless) steel aren’t used in modern installations, but other factors could be at play.
Can you describe the failure better – “cracking” as in through the units, or cracking just at the glaze coating, for instance?
Terracotta has a glaze from the factory. sounds like manufacturing defect, nothing to do with installation.