Mortar mix for Indian sandstone

Techniques for laying Indian sandstone paving are different, the thickness variation of Indian Sandstone requires it to be laid on a 4 parts sharp sand: 1 part cement semi dry mix. The wetter mix allows the finished height of individual paving slabs to be adjusted to counter the variation in thickness. When mixing mortar for natural stone it is important that the correct amount of water is added. If the mix is too dry it will lack the flexibility required to adjust the finished height of the paving slabs. If the mix is too wet then the slabs can sometimes sink under their own weight. Another side effect of a wet mix is leaching, this is when moisture from the mortar leaches through the slabs leaving white staining and residue on the paving surface. You need to be particularly aware of leaching when laying some of the softer varieties of sawn sandstone.

I prefer to use part plastering sand part sharp sand and cement it gives it a smoother finish rather than just sharp sand Semi dry and plus gives it a better colour rather than grey