Indian Stone

Excavate
Choose the area where you want to lay your sandstone paving making sure it’s firm, level and well-drained. Mark out the area with spray paint. Dig the spray-painted area to the correct depth for intended use – plus the depth of the paving – removing all vegetation and top soil  (the finished surface depth should be a minimum of 150mm below damp proof course of house).

Foundation layer
Fill and compact a 50mm layer of sub-base material (crushed stone 40mm – dust). Repeat this process so the sub-base has an overall depth of 100mm for areas of pedestrian use, or a minimum of 150mm for vehicular use up to 3.5 ton. Ensure the area has falls that are adequate surface water run-off.

Wash them
Wash the units with a sponge and clean water to remove any dust and dirt.

Prime time
Prime the backs of the units with a proprietary priming product or a fine mortar slurry: either pva/water solution and cement, or ideally a SBR (synthetic rubber) polymer/water and cement. The primer should be applied to each tile prior to bedding.

Mixing up a bedding mortar
Create a mortar mix of four parts sand to one part cement and water. The mix should be of a “wet” workable consistency.

Level your bedding mortar
Working in a small area, add a full mortar bed to the area and level it off so the bed is approximately 30mm in thickness.

Lay it down
Lay your sandstone paving slabs in the mortar bed placing them 8 to 10mm apart. Bed the paving down firmly into the mortar by tapping the slabs lightly with a rubber mallet.

Jointing up
Use a trowel to fill the joints with a mortar mix of four parts sand to one part cement. The mix should be of a “wet” workable consistency. Compress mortar mix into the joints with pointing tool.
An alternative to traditional mortar joints is a resin bound jointing system. These set as hard as traditional mortar but have the advantage of being much faster to install. The standard method of installing a resin based jointing product is to wash and brush the product in with a continuously running hose pipe and brush. Joints are topped up where required then the area is lightly rinsed to wash any oily residue away. Finally the joints can be shaped with a trowel or joiner if a smoother finish is wanted to the joint surface.

Leave it be
Leave your sandstone paving to set for at least 24 hours before walking on it – allow longer in wet weather.