I'm trying to pitch a flat section of roof on my house because it leaks. Flat roofs are sometimes flat because of too-low or badly-defined building height limits.

Boringness also probably comes from increasing numbers of people involved in approvals. Try getting some wild thing through public hearings and city councils. Much harder than a cube. The boringness is a feature, not a bug.

I bet there's a ton of other factors too, like the cited attention cost of detail.

The way I see it, in Central Europe the reason for a flat roof on a single family home is mostly cost advantage (on short sight) or architectural.

Someone said: There are two types of flat roofs: Those that are leaky and those that are not leaky yet.

I really wonder how is that so. Even in my home country which is easily in the bottom 10% of Europe's poorest I lived in a building built in 1977 (!) with flat roof. It never had a leak until this year, and on the first sign of it tenants found some company to install some membrane and gave them 10 year no-matter-what warranty on it. And it was super cheap when divided on 30 owners. And we're talking about a country with average monthly salary of $400 or so.

I've heard this stated a few times - that flat roofs are meaningfully cheaper - but really? How? The tiny bit of extra material to add a bit of height to some ridge seems trivial. Where's the cost?

Hardly any new houses are built with flat roofs. That trend is mostly dead. Commercial buildings still have flat roofs because they need a place to mount stuff like HVAC and antennas.

It's partly a climate thing. Flat roofs in areas with snow are begging for all sorts of leaks and general snow load problems. There are probably houses in the Northeast built with flat roofs. They probably also have leak issues. Heck, houses with sloped roofs often have problems at junctions and with ice dams. Commercial properties are, in part of the reasons you cite.

Lots of places in the northeast with flat roofs. Particularly dense city centers where snow falling off sloped roofs poses a danger to busy pedestrian sidewalks. As long as you keep your roof maintained it’ll last a long time. And “flat” roofs are always angled at like 1-2 degrees to ensure proper drainage.

I don’t know where you are but in Seattle almost every new house has some sort of boxy flat-roofed design

I've always assumed that the boxy things were more about maximizing saleable square footage and less about architecture. Also, "rooftop balcony" is a nice price adder!

I don't hate the boxy things, I just hate that there's nothing else being built in Seattle right now except boxy things. And they're not much to look at.

Here in Germany next to all new apartment buildings (usually 3-5 stories) have flat roofs.

Alas, in the US we are not as wise to the ways of steel-reinforced concrete construction as you guys are :(

I think (hope) that in Germany we are still using brick and mortar construction? Or at least some modular wall elements.

At least I have not really seen those rebar and concrete skeletons that are a common sight basically everywhere else.

3-5 story buildings in the US are usually just wood frame. Any brick or stone is just a 1-2” thick panel they hang on the outside of the building.

Yes, a common construction are these five-over-ones, with a steel-reinforced concrete first floor (for retail) and then wood framed 5-story apartments above.

This podcast goes over what an absolute disaster this type of construction is [0], but for apartments in most major US cities west of the Mississippi, it is hard to avoid _some_ sort of wood framing.

[0] https://www.youtube.com/watch?v=xVodkE47aLw

> we got flat roofs from bauhaus philosophy.

Not really. Frank Lloyd Wright was building with flat roofs a decade before the Bauhaus school even opened. But it was certainly an artistic endeavour and he’s a great example of somebody who had an adversarial relationship with pretty much everybody.

Wright used flat roofs and I'm sure other folks did before him, but bauhaus was the intellectually dominant influence on schools of architecture in the west.

https://en.wikipedia.org/wiki/From_Bauhaus_to_Our_House

Besides the Larkin building (a factory), what did he build with predominantly flat roofs? I don't think there's a home he built prior to fallingwater that was anything close to what Bauhaus did.