Walkways on Rooftops
General Information Regarding Paving Slabs on Roofs and Garage Roofs
Rooftops are being used holistically at an ever increasing rate. Nearly everything that can be realised on the ground is now possible on roofs too, provided the right technology is used. For instance, long lasting and functioning walkways and driveways on rooftops require well-engineered systems. These assure the continuance of the roof functions (e.g. waterproofness, drainage, thermal and sound insulation) and cater for horizontal forces generated by accelerating, breaking and steering.
Drainage: As opposed to landscaped rooftops where water is to be held back and run-off is to be delayed, walkways and driveways need most of the rainwater to be quickly drained off the surface. Hence, the drainage points should allow for 2 levels of drainage: at the surface level and at the lower drainage level. The ZinCo product range provides the necessary system superstructures and accessories to cater for this.
Gradients: The flat roof guidelines and DIN 18195 determine a minimum gradient of 2 % for the waterproofing level, but they also regulate constructions with smaller gradients. “Stilted paths” can be built at 0° slope, as the rainwater is drained away through the interstices ; standing water is therefore no issue. Concrete or asphalt flooring should be built with a minimum slope of 1.5 %, paved flooring with a gradient of at least 2 %. What is more, the drainage of the relevant area should not be done in the direction of the building. All this must be considered in the preliminary planning stages.
The most common usage of rooftops: If walkways and driveways are combined with Green Roofs, not only the drainage and the compressive strength of the system are important, but also its water retention capacity. With Floradrain® FD 40-E as core element of the construction, all requirements are fulfilled for a long-lasting functionality. Depending on its laying procedure, FD40-E will either retain water or let it pass through. Particular attention during planning and implementation should be paid to the transition areas between the paving slabs and the landscaping.