Looks like the depth of the joints is not deep enough to me.
There's various options to resolve this the way I would do it.
If adamant you want it done with sand and cement whatever ratio and ad mixtures you go with it looks like all the joints would need to be raked out with a ginder or chisel...
This site uses cookies to help personalise content, tailor your experience and to keep you logged in if you register.
By continuing to use this site, you are consenting to our use of cookies.