Hello everyone,
This is about the new construction of a single-family house with a flat roof. I have a main roof of 120 sqm (1,292 sq ft), a garage roof of 80 sqm (861 sq ft), and two balconies with masonry parapets. The roof slope is 2° and the main and garage roofs are covered with standard gravel. The construction company has installed three downspouts on the main roof and two downspouts on the garage roof for drainage. According to DIN standards, flat roofs require an emergency drainage system that is not connected to the sewer system. This is not present in my case, with the explanation that additional "regular" downspouts were installed. According to DIN, only one drainage pipe (DN100 or DN80) would be required for each.
However, emergency drainage is now being retrofitted on the two balconiesârequiring drilling through the installed membrane waterproofing.
I am a bit skeptical regarding the main roof and garage. Does anyone have experience with whether this really works without emergency drainage?
Thanks for any input 🙂
This is about the new construction of a single-family house with a flat roof. I have a main roof of 120 sqm (1,292 sq ft), a garage roof of 80 sqm (861 sq ft), and two balconies with masonry parapets. The roof slope is 2° and the main and garage roofs are covered with standard gravel. The construction company has installed three downspouts on the main roof and two downspouts on the garage roof for drainage. According to DIN standards, flat roofs require an emergency drainage system that is not connected to the sewer system. This is not present in my case, with the explanation that additional "regular" downspouts were installed. According to DIN, only one drainage pipe (DN100 or DN80) would be required for each.
However, emergency drainage is now being retrofitted on the two balconiesârequiring drilling through the installed membrane waterproofing.
I am a bit skeptical regarding the main roof and garage. Does anyone have experience with whether this really works without emergency drainage?
Thanks for any input 🙂
K
k-man20218 Jun 2021 19:25For us, the pipe runs from the roof into an open water collection box and then into the downpipe. If the downpipe is clogged, the box overflows. Thatâs also how I know it from other flat roofs with external drainage.
So maybe just retrofitting a collection box for each? Itâs unlikely that all three drainpipes would clog.
So maybe just retrofitting a collection box for each? Itâs unlikely that all three drainpipes would clog.