How much glue is too much for tiling?

PatDIY_Dad

Question if there is any other tilers here? We actually have a tiler doing tiles in our under cover pergola area at the moment and so far his doing a great job

The concrete substrate has alot of fall and was not very flat in some areas and uneven so the tiler using ALOT of glue to compensate

The high spots his using say about 10mm thickness of glue under tile and the lower parts of the concrete I measured about 40mm thickness of glue

I was more curious to know thats all

MitchellMc

Hi @PatDIY_Dad,

It really depends on the adhesive being used and its recommended thickness. Many tile adhesives specify a minimum of around 3mm and a maximum of 10mm. If too much adhesive is applied, it can shrink as it cures, potentially leading to the tiles pulling away or becoming loose over time.

If the concrete surface had significant variations in height, it would have been better to level it first using a self-levelling compound or screed before tiling. While adhesive can compensate for minor unevenness, 40mm is well beyond the usual recommended thickness for most products. You might want to check with the tiler or look up the specifications for the adhesive they are using to ensure it's suitable for that application.

Please let me know if you have any questions.

Mitchell