The roof is about 30 years old and urgently needs to be replaced, the substance is no longer adequate.
Unfortunately, because of the weight, installing shingles is not possible. The maximum weight is about 15 kg / sq. m.
Does anyone have any experience with alternative roofs for residential buildings where shingles cannot be used – because of the weight?
It would be important to me that it is not as noisy, especially when it rains in an apartment building, which can be the case with a metal roof.
We have a tin roof, the sheets look like shingles. If the roof has enough insulation, you won't hear anything from the rain inside. It has lasted on our roof for 20 years, and I would use it again under the same circumstances. They come in different lengths, and you can find the right length. But it takes several people to install them, they are not heavy, but they are bulky.
There are lightweight concrete shingles such as Braas Doppel-S Aerolox. Roofing shingles are always heavy. Plastic shingles add 5-6 pounds per square meter.
A so called multi-layered roofing system would be a possible option, there are manufacturers, information, etc. online about it