Hairline cracks in grout (newly installed kitchen tile)

[cheesensweets]

I had 12x12 ceramic tiles installed in my kitchen back in February. I've had the contractors back twice to replace tiles that I found to be high on one of the edges. I'm not sure if the guy used spacers - I am finding high sides on several tiles. Anyhow, the newest problem I am having is hairline cracks along the grout lines. Some of the cracks go for a long way and some are just the length of a tile. I believe the floor was installed over hardibacker that was placed over the original linoleum floor (house was built in 1975). Are these cracks typical of ceramic floors? Do I need to have the contractor back to either replace tiles or replace grout?

 

[Meblin]

Sounds like the adhesive and grout used were not flexible.

What is hardibacker? The norm is to use 18mm ply and tile on top, but it does depend on what your base floor is mad of.

I would think the heat is making everything expand and the grout/adhesive cannot take it so is cracking.

Meblin

 

[Sandy Beech]

What is hardibacker?
Meblin

Hardibacker is similar to Aquapanel but available in a flooring grade as well. There website says it is OK to use over existing lino but not cushion floor or flaoting. www.jameshardieeu.com or is it co.uk?