Porous concrete solid roof as a tent roof for a city villa

Hello everyone,

I have been following along here for a while and now finally we are about to start building our house. Currently, we are planning a city villa (external shell 42.5 aerated concrete, internal walls calcium silicate brick) with 2 full floors on a plot in the second row with 100m as the crow flies to the pedestrian zone.

City villas are usually built with a 22-degree roof pitch and hipped roof. Our idea for the roof was a 35-degree roof pitch, pyramid roof, and a solid aerated concrete roof with 2-3 skylights. Why this choice? On the one hand, we want to keep the expansion reserve upstairs to convert it into an office and another children's room in a year, hence the 35-degree roof pitch instead of 22 degrees. On the other hand, due to the dense development around us, soundproofing is an issue and the photovoltaic system is firmly planned. According to a friend who is an architect, with free choice of the roof, from the perspective of sound and radiation protection (because of the photovoltaic system), a solid roof is preferable.

According to Ytong, any roof shape can be implemented as a solid roof. So far, according to my research, I have mainly only found a solid roof as a gable roof. Does anyone here have a solid roof as a pyramid roof and can possibly help with photos, and does doing it as we have envisaged even make sense?

If it matters, we are still undecided about the upper floor ceiling, either wooden beam ceiling or concrete ceiling.

Greetings from the Ruhr area

We do not know your planned house, and therefore many details as well, whose relevance you may possibly underestimate. A tent roof and photovoltaics initially sound like an unwise combination - or maybe not? - that significantly depends on whether this results in pitched roof surfaces on those sides that are favorably positioned for it. An aerial photo would be helpful, as well as cadastral excerpts and the like. How much knee wall would be possible or planned?

If it matters, we are still undecided about the upper floor ceiling, either a wooden beam ceiling or a concrete ceiling.

Regarding the statics of a roof truss, you do not seem to be overly knowledgeable - at least you realize it might matter. It would be sensible for you to tell considerably more about the house and property. Otherwise, neither optimizing advice can be given nor even the seemingly simple question answered of how a massive tent roof could be constructed here. What is the reason against a gable roof or shed roof, which is not least significantly more expansion-friendly?

An architect who wants to build a concrete roof for radiation protection reasons belongs in the [Klapse] in my opinion.

In my opinion, an architect who wants to build a concrete roof for radiation protection reasons belongs in the madhouse.

I think that's good. At least as a resident you can take off the aluminum hat at home

In my opinion, an architect who wants to build a concrete roof for radiation protection reasons belongs in a loony bin.

Hahahaha, that made me laugh too. I mean, I’ve been reading here for 1.5 years and have learned quite a bit, but the radiation thing even seemed weird to me.
My first thought was: With so many photovoltaic systems in the country, either most of them would have to have a concrete roof, which certainly isn’t the case, or the danger is being exaggerated more than it actually is, and apparently that’s the case here.
Anyway, just for possible radiation protection aspects, if any, I wouldn’t pay the extra cost for a solid roof.
What about the other aspects like sound insulation and the airtightness of a solid roof?
Regarding airtightness, as a layman, I would guess there are advantages compared to a conventional roof structure; when it comes to sound insulation, I lack the experience to judge.

We don’t know your planned house, and thus also many details whose relevance you might be underestimating. Tent roof and photovoltaic sounds at first like an unwise combination – or maybe not? – it depends significantly on whether this results in inclined roof surfaces on the sides that are favorable for it. An aerial photo would be helpful, as well as cadastral excerpts and the like. How much knee wall would be possible or planned?

Regarding the statics of a roof frame, you don’t seem to be excessively knowledgeable – at least you realize it might play a role. It would be sensible for you to tell us a lot more about the house and the plot. Without that, neither optimizing advice nor even the seemingly simple question of how a massive tent roof could be constructed here can be answered. What is the reason against a not least considerably easier to expand gable or shed roof?

Regarding the gable roof, we also see the advantages of easier expansion and simpler roof construction.
What spoke against it: The look of a city villa with a gable roof leaves a lot to be desired with a square building body 10x10 m, and we have to stay within the building envelope of 10x10 m.
And the same tin-foil-hat architect said that the distribution of the photovoltaic system on east, south, and west sides of a tent roof would ensure a constant daily yield.
Attached is the requested aerial photo with the approximate arrangement of the building body. We don’t yet have information on the knee wall, only that the planned tent roof has a 50 cm roof overhang. The development plan allows 2 full stories and pitched roofs (GD), with no specified ridge or eaves heights.

And the same conspiracy theorist architect claimed that distributing the photovoltaic system on the east, south, and west surfaces of a tent roof would provide a constant daily yield.

I can agree that the yield actually comes in quite evenly. The 70% rule doesn't hurt either.