Roof renovation standing seam roof
Roof renovation and insulation for a standing seam roof
This roof of the waterworks in Dormagen is covered with standing seam profiles.
With these profiles, large spans could be covered without transverse joints with a weakly designed substructure.
The profiles are laid without joints in the longitudinal direction. Due to the enormous length of the aluminum profiles, in this case more than 30 m, the expansion caused by heat or cold is inevitably also enormous. The strong working of the roof outer shell has resulted in a negative slope at the outer edges (in the area of the gutters).
Constant standing water has caused dirt and leaves to build up and further impede proper water drainage.
Due to the negative slope, however, rainwater can also run inwards along the underside of the sheets and drip off there.
It has been shown that the inlet sheets in particular, which are supposed to ensure water drainage into the gutters at the edge of the roof, act like inlet funnels and promote water penetration into the interior.
In order to prevent the strong linear expansion, it is necessary to insulate the roof on the outside.
Due to the high profile, it was advisable to first cover the profiles with polystyrene sheets and then insulate them completely with a 45 mm thick insulation layer of polyurethane foam.
The polyurethane foam is applied to the finished polystyrene insulation in multiple layers using a spray process.
This produces a homogeneous surface which, in addition to optimum thermal insulation, also provides reliable roof waterproofing.
PURelastik liquid plastic was sprayed onto the finished foam surface to protect it from UV radiation.
PURelastik liquid plastic forms a highly elastic film on the roof surface, which forms an intensive bond with the substrate.
Slate chippings are blown into the last layer of PURelastik while it is still liquid to prevent possible damage from birds.