Stone Paving
Stone paving as used in plazas, promenades and street-scapes is usually  produced from either granite, bluestone or sandstone with any number of surface  finish possibilities.

Stone paving units are precut and pre-finished to specification before being  delivered to site, ready for installation.

Thickness of paving is generally based on the mass of the largest vehicle  accessing the paving. The heavier the vehicle, the thicker the paving. This is  not necessarily the case as failure in compression will only happen under  extreme circumstances. Failure is more likely to occur from poor bedding or substructure movement creating voids under the paving. When this is the case the  paver is then subject to shear or tensile loads causing it to fracture. It is  imperative that the bedding and the sub-structure are finished properly and then there is not very often a case where paving would have to exceed 50mm. This will also depend on the size of the paver, obviously the larger the paver the thicker it must be to cope with substructural movement.

Interior tiling is the same as for paving but on a much smaller scale. There  are never the same live loads on interior tiling than external paving but it is still imperative that the bed be finished perfectly and the substructure is  structurally adequate. For granite tiles the thickness can be down to 10mm, lower for some slates and of course ceramic tiles, but generally 20mm stone  tiles are recommended indoors.

Stone Kerbing

Stone Kerbs are solid lengths of stone, usually around 150-200mm thick by 150mm-200mm wide and are used as edging or  borders around gardens, streets, parking areas and in parks. They can be used to protect gardens, paving and also are used to direct the flow of water. Around the streets of Melbourne the majority of kerbing is made out of  Bluestone.

Paving & Kerbing Installation Methods

Stone paving and kerbing can be installed in one of two main methods.  Consideration should be given to each of the methods, the type of stone being  used, and the type of usage before making a selection for a specific installation.

Pavers should be installed in a full mortar bed consisting of one part cement (Portland Type A) and form three to five parts of sand. A nominal mortar bed of  30mm is recommended, however this can be altered slightly to suit specific  requirements. A bond coat of cement slurry is also recommended however an  approved commercial adhesive, applied in accordance with the manufacturers recommendations may be used in its place. All water used in the installation process (including that in the concrete mix) should be fresh, clean tap water, free from contaminants which may damage the stone work.

The following installation procedure should be followed in general.  Variations to this procedure may occur depending on the size, thickness and  material type being laid and the installation type chosen:

> Sweep concrete sub-base and remove all foreign materials

> Prepare mortar mix

> Mix slurry mix

> Dampen concrete sub-base with clean water

> Using a hand broom, apply slurry mix to concrete (approximately 1 mm thick)  to area which will not exceed extent of paving to be immediately laid.Slurry must remain wet to carry out next step.

> Shovel mortar mix into position and loosely screed so that combined bed and  stone thickness is higher than desired surface level by 5mm.

> Wipe down the backs of stone with damp cloth prior to bedding (do not soak pavers). Hit paver evenly over entire surface with a rubber mallet to  approximately 2mm higher than the desired finished level.

> Remove stone, by means of lifting tool or by hand, fill voids with additional mortar and then loosen up bed lightly by crisscrossing hand trowel through bed.

> Apply coating of slurry to underside of paving stone, ensuring that the  initial application is stiffly brushed into the stone in a rotating motion, and  build up slurry thickness to approximately 1mm.

> Bed down stone as per step (6) to finished surface level.

> Trowel fill any voids with mortar as front edge and/or front corners of  stone.

> Discard excess mortar.

> On completion cover stone with hessian sheets and spray water mist. Allow to remain moist for 12 hours minimum.

> To the satisfaction of the Engineer, place wooden boards, or similar over paving which is subject to pedestrian traffic within the first 12 hours if curing.

> After a minimum of 12 hours curing the joints may be grouted. Where  necessary remove foreign material from within the joints.

> Dampen joints with sponge and pour grout mix into joints ensuring full penetration for the thickness of the paving slab by lightly tamping down a  trowel edge into the grouting mix. Use a rubber squeegee to spread grout evenly into all joints until filled flush with the top of the stone.

> Remove excess grout, allow initial set and lightly broom of remaining excess perpendicular to joints.

> Wipe stone clean with a damp sponge.

Waterproof membranes and polyethylene overlay sheets should be avoided where  possible due to the risk of damage during the installation process.

If reinforcement is necessary it should be limited to galvanised wire mesh only so as to avoid any possible reaction/staining between steel reinforcing and the stone.