Laying external stairs - The drainage
In order to prevent waterlogging below the first stage from becoming waterlogged, ideally a small layer of fine gravel should be introduced there to accelerate the final drainage into the soil (see drawing above).
For this reason, the first riser should not be placed on, but in front of the pavement and, if necessary, supported with two small elbows.
Due to the additional use of drain mats Penetrating water can be dissipated more reliably. However, the use of drain mats is both costly and not without risk. As the bond between the natural stone and the concrete substrate is interrupted by the mat. If you would like further information regarding the use of drainage mats for external stairs, we recommend the video in the upper right corner of this page.
When laying, each part of the natural stone covering on the back with a bonding slurry be painted. This ensures full contact between natural stone and drainage mortar. Cavities are prevented in this way.
Laying external stairs - the slope
The natural stone steps must of course be laid with a slope. For flamed materials we recommend at least 2%. This means at a level of eg 28 cm depth a slope of approx. >6 millimeters and with a pedestal of 100 cm depth a slope of >2 centimetres.
Joints must be with one special grout or a special one Silicone for natural stone be closed.
If you use the stairs after laying with a Fleckstop impregnate, or with a Color Intensifier After treatment, this may only be done after the mortar has dried out under the covering. The moisture from the mortar bed must largely evaporate through the stone. Depending on the season, this may take 4-12 weeks.
All statements without guarantee.