- Wide brush
- Flat notched trowel
- Large bucket to mix the glue
- Bushhammer (depending on the support)
The different supports for the natural facing stone are :
- Indoor or outdoor
- Old or new building
- Concrete banché (if bush-hammered)
- Cement, Agglomerated, Cellular Concrete
- Plasterboard (better to slightly streak the surface to ensure a perfect adhesion)
- Polystyrene insulation and others
- Tiling (application of a bonding resin beforehand).
Any other support will not be suitable for this type of installation, except in special cases (paneling, wood, metal, etc.) with specific techniques of attachment.
Make sure the base of the support can withstand the weight of the sawed stone and the support is healthy (cracks, various degradations, etc ...). Check the humidity at the support level, knowing that too much moisture will prevent the glue from adhering properly to it. Depending on the altitude and the frost propensity, define which type of glue will be most suitable for laying.
Remove layers of coatings or materials that could prevent the proper laying of sawn stone.
In case of shuttered concrete, bulge the surface to ensure better grip.
Thoroughly clean all exterior concrete supports before laying.
Apply the primary layer and let dry 12 hours before applying the glue.
In some cases (external insulation, bush-hammered concrete), drill holes spaced 40cm (horizontally and vertically) reaching the hard part; then apply a first coat of glue and directly apply the fiberglass net to the still fresh surface. Insert plastic dowels into previously drilled holes; push them completely. Put a layer of glue on the net using a flat trowel and let it dry for another 6 hours before final laying.
LAYING WITH JOINTS
In any case, always start laying by the angles!
Then only, start laying your first facing stones at the bottom of the face to cover.
In a large bucket, pour the powdered glue and add the water and mix with a mixer. Always proceed in small quantities.
Use a high quality flexible thin-set mortar following all the manufacturer's recommendations for mixing.
You must double glue, on the wall and on the sawn stone with a notched spatula.
Then apply the glue with the spatula spreading it directly on the surface to be covered.
Subsequently, remove the remains of dust and other impurities from the back of the sawn stones with clear water and then glue the back of the sawn stone and apply it directly on the wall by pressing heavily.
Move back and forth vertically and horizontally to ensure optimum grip.
Place small pieces of wood between each stone to the desired joint thickness, then remove all the wood blocks after the glue dries.
After a few hours of drying, join the facing stones. Using a kneader, prepare the special joint for your sawed facing stones, which may be a natural or tinted lime plaster. Follow the manufacturer's instructions for using the mortar carefully.
There are several techniques for jointing:
PLASTIC TROWEL AND JOINT SPATULA
Place a good amount of mortar on your large plastic trowel and bring it close to the surface to be grouted.
Using your joint spatula, first fill the vertical joints, then the horizontal joints.
Once the joints are filled, smooth them with the end of the joint spatula. Once the joint is almost dry, brush over the entire surface to remove excess mortar. Always work square meter per square meter.
Take your grout bag and make the joint mix giving it a fairly liquid consistency so that it penetrates well into all pores. Fill the joints more or less generously according to the expected result: joints leveled or hollowed out. When the joint begins to harden, carefully remove the excess with a brush or a broom (leveled joint) or brush the joints with a soft steel brush while digging a few millimeters (hollowed out joint).
LAYING WITHOUT JOINT: 'DRY LAYING'
In any case, always start laying by the angles!
Ensuite seulement, commencez la pose de vos premières pierres de parement en bas de la façade.
Use a high quality flexible thin-set mortar following the manufacturer's recommendations for mixing.
First apply glue on the wall and on the sawn stone with a notched trowel.
Apply the glue with the trowel by spreading it directly on the surface to be covered with sawn stones.
Remove the remains of dust and other impurities from the back of the sawn stones with clear water.
Then glue the back of the sawn stone and apply it directly to the wall by pressing strongly.
For better adhesion, move back and forth horizontally and vertically to ensure optimum grip (You can optionally lightly pat the sawn stone with a rubber mallet).
For a more natural look, opt for a staggered pose, with vertical joints never to be aligned for a better aesthetic appearance. Finally fill the spaces too important with small stones and other falls of sawn stones.
Finally, immediately remove with a wet sponge any traces of glue that may be present on the visible face of the stones. In case of rough facing stones, rub gently so that the glue does not penetrate into the interstices.
HELP IN IMAGES