Additional information regarding exterior flooring installation techniques:
Exterior floor with drainage layer of granular material or sand bed.
This method is mainly used when placing smaller elements such as cobblestones. On top of a crushed stone layer or a draining concrete layer. The natural stone is laid in a bed of rough sand and mixed with cement. Vibrate the whole well with vibration plate and fill the joints with silver sand. Then spray and brush. More and more often it is opted for placement on a layer of limestone 8cm. Fill the joints with finer limestone. (see sketch of principle).
Only applicable for larger tiles with a laying mortar on a stabilized sand bed. When installing tiles with a low absorption, the bottom of the tile should be very well dusted and an adhesive liquid applied. The laying mortar must be provided with an additive.
Exterior floor with draining foundation or drainage mat
The use of a reinforcement mesh in the screed is absolutely necessary in order to avoid the risk of cracks – cracks in temperature fluctuations. The tiles can be glued or placed in a thin mortar layer of 2 cm. (see sketch below).
Floor laid on tile supports or drainage mat
There are 2 techniques: an adhering and non-adhering build-up, in the case of a non-adhering build-up the water can drain immediately, so that the tiles can dry quickly and the risk of blooming is prevented.
Not adhesive: by means of tile supports placed on the seal. A membrane is placed under tile supports. The tiles at least 3 cm thick are placed loosely on the tile supports, the height under tiles is at least 5 cm in order to obtain good ventilation and to promote water drainage. Always leave the joints open. To promote favorable drainage, regularly remove dirt under and between the tiles. (see sketch) Adhesive floor: The tiles are placed in a mortar bed or glued. A drainage mat is placed on the waterproofing layer, then a screed with a reinforcement net, glued the tiles or placed in a mortar layer.
The natural stone must be frost resistant and resistant to chemical influences, have good bending strength and can withstand temperature fluctuations. It is advisable to always consult the technical data sheet first. The thickness depends on the nature of the rock and the way of anchoring. Plates of 2cm are possible, but often a different technique will have to be applied. The anchors must always be made of stainless steel. There are different systems, including mortar anchors, distance anchors, quick-mounting anchors. Grouting is always done with a flexible joint.
Always leave at least 20mm at the rear for good ventilation of facade panels.
Placement of outdoor terraces
When installing outdoor terraces, a top layer of rough (coarse) sand must always be used (stabilized). The advantage of this is that any thickness differences can then easily be knocked out. Just paving the sand bed is not enough at all.
The joint should also have a minimum width of 5-8 mm and a minimum depth of 30 mm, so that the elastic joint mortar can be easily swept in. The advantage is that the tiles become much more stable and the hollow and convexity of tiles can be absorbed in the joint.