10 things about roofterraces
Always startup with PavePad 15 mm as a minimum. This prevents sand and dust from building up underneath the terrace as a regular rainfall or garden hose will clear it out. Sand doesn’t belong on a roof! If you have clearance issues, see the technique gallery for help.
Place the PavePad as close to the wall as possible, to avoid gaps. If the shape of the roof edge prevents you from getting close enough, apply one of the techniques in the photos or use an alternative approach such as, gravel, metal frame or ventilated tubing/piping (ormally used to prevent snow or birds from accessing underneath waved roofing). It is important not to leave room for leafs etc. to pass underneath the paved area.
PavePad 15 mm is minimum. If the space is limited it is better to use a smaller dimension slab/tile in for instance the first 2 rows (choose 40 mm concrete slabs in those rows instead of 50 mm). In general you are able to change tile or grid dimensions (material strength) as you please with the PavePad system. You can do so without affecting your upper surface.
At first place a row going straight out in a line. Secondly, make a row going to the side (towards nearest wall or border). Now you have made an diagonal for placing your lines and pattern. Also the first reactions from the bearing layer will show now, whether it will give due to load strain – leading to more adjustments. See more about the subject: bearing layer in the bottom of the page.
Certain roof constructions are better for roof terraces than others. The firmer the surface the less it will give way when applied with weight. A terrace placed directly on insulation batts (hard batts) will gradually sink when applied with more weight leaving a lot of readjustments. In those cases we advise to place a waterproof veneer sheet between the layers. This will result in more strength. However, in most cases the hard batt solution will lead to an increase of PavePad material - how much is almost impossible to calculate as it will vary from case to case. A concrete deck or a membrane based on for instance foam glass will be steady throughout the process.
It is always up to the owner/construction manager to seek advice from an engineer for load calculations and structural acceptance, prior to establishing a roof terrace.