Techo-Blocs - Interlocking bricks

Has anyone had a problem with these bricks staining/changing color? I had grey Techo-Blocs placed in a 2300 sq. ft. area and and parts of the area are now turning brown.

 

Have you contacted the supplier or dealer for an opinion?

How old is the installation?

I looked at the web site and it was very feeble, at best, regarding any technical information. They appear to be interlocking concrete paving stones. The gray units may or may not be pigmented. The pigmented units are supposedly made using an iron oxide pigment. The iron oxides are known to be good for color stability and permanence.

Some producers (very few) may use carbon black (much cheaper) instead of iron oxide to get gray colors. This material is not as permanent and usually fades instead of changing colors.

Dick

 

Post a picture.