Exterior Tile Rusting! Any ideas why?

Hello, I performed a maintenance inspection on a home that had tiles used as siding and some of the tiles had rust stains. Any ideas what caused this and what would you recommend?

Steel nails used on the window nailing flange.

Big problems ahead IMHO.

Water is getting behind the times and or window flashing.

Thats surely a new one. Where are you located? I guess all masonry is still moisture absorbant.

Could it be a surface problem, e.g. a rusty screw that once held a screen or pipe to the wall?

If not I’d wet test that wall, and figure out how the big volume of water is getting behind the wall. Doing anything to that tile wall is going to be super expensive!

This is a bleed-through condition. There are numerous sources of water intrusion and formation of moisture within a wall to consider. There is a 100% chance that you have excessive moisture within the wall for one reason or another.

How extensive is this problem throughout the entire building?

If there is no surface penetration at the rust spots, then this is a bleedthrough penetration that requires follow-up analysis which is beyond the insured capacity of a home inspector.

Give me a call, I do these all a time. More information is definitely required.

Other things to consider:

  1. Was there a drainage plane? Was a weep screed present? That’s a stucco wall with tile as the outer coat. A weep screed is required by the IRC.

  2. There should be a backer rod and caulk present where the tile meets the window to prevent a “brick bind” condition which can crack the window frame and allow unnoticed water entry into the wall system.

If you already inspected it once, it’s gonna be hard to call out that serious stuff now. I don’t envy you if that’s the case.

This could be Pyrite staining.IMO
Looking for more evidence…

Reuben have any photos from further back?

Mineral occlusion if it was a stone tile.