I have a similar thing with flat roofs. They are terrible. When you are 5 years old, you already learn to draw houses with a pointy roof. The pointy roof has been invented about a 100 times in history, as people were looking for the best shape. The wave shaped roof tile with 2 waves per tile has been invented about 3 times in history as people were looking for the best shape. The advantages of a pointy roof over a flat roof:

Rain flows off. Yes, you can give a flat roof a small inclination, but rain will not flow as well, and if your roof tilts a small bit during the decades, it can become horizontal again.
Snow falls off, reducing the chance that the roof collapses under the weight of heavy snow.
It is lighter and cheaper, as you can use thinner materials. This is because pointy is a stronger shape than flat.
It gives more interior space.
It allows more sunlight to reach the street.
It has a smaller area-to-vloume-ratio through with heat can escape.
Solar panels get a higher efficiency.
It allows the roof to be made out of wavy roof tiles which provide the following advantages:
Roofs designed with wavy roof tiles can be constructed when it rains.
When a tile breaks, you can easily replace it, without having to cut it loose from the tiles next to it.
Roof tiles do not fracture upon an uneven heat distribution. Meanwhile, the advantages of flat roofs are:
If you design an apartment building, you can copy and paste the interior. (Thus less work for the architect.)
A horizontal line is one segment less to draw compared to two diagonals. (Thus less work for the architect.)
If a city has the same height restrictions for flat roofed buildings as for pointy roofed buildings, and the architect is too lazy to go to the city council to explain to them that that doesn't make sense, the architect can design a building with more volume by making the roof flat. In other words: the only reason any architect would design a building with a flat roof is because they are either lazy or they have no idea what they are doing.

[–] Cort@lemmy.world 9 points 2 weeks ago* (last edited 2 weeks ago) (5 children)

It is lighter and cheaper, as you can use thinner materials. This is because pointy is a stronger shape than flat.

It gives more interior space.

If you're using lighter cheaper materials you'll need all the added interior space for roof trusses, none of it will be livable space.

It allows more sunlight to reach the street.

No, for the same amount of occupiable space the shorter flat roof blocks less light than a standard 10:12 or 12:12 roof

It has a smaller area-to-volume-ratio through which heat can escape.

The greater surface area of a pitched roof means this is absolutely not true. The hypotenuse is always longer than either leg.

Solar panels get a higher efficiency.

This one actually depends on latitude, equatorialy it's better flat. And don't forget that the minimum summer angle is limited by the pitched roof.

If a city has the same height restrictions for flat roofed buildings as for pointy roofed buildings, and the architect is too lazy to go to the city council to explain to them that that doesn't make sense, the architect can design a building with more volume by making the roof flat.

No it makes perfect sense. It goes back to your comment on letting sunlight through to the street. The maximum height is the maximum height so everyone gets the same amount of light.

In other words: ~~the only reason any architect would design a building with a flat roof is because they are either lazy or they have no idea what they are doing.~~ this guy thinks their habitat is the only kind over the whole planet and can't imagine people living in areas where snow load wouldn't need to be considered.

[–] TheLazyNerd@europe.pub 1 points 2 days ago

If you’re using lighter cheaper materials No, I'm using the same materials. sloped roofs are simply a stronger geometry, allowing roofs to be cheaper and lighter by using less material.

No, for the same amount of occupiable space the shorter flat roof blocks less light than a standard 10:12 or 12:12 roof Incorrect. While the highest point of a sloped roof is higher than the highest point of a flat roof, the lowest point is lower. This means that for medium high sun angles sloped roofs provide won't block the sunlight, while flat roofs do, and for low sun angles it is the other way around. However, there is not much sunlight anyway at low angles.

The greater surface area of a pitched roof means this is absolutely not true. The hypotenuse is always longer than either leg. That's a basic math fail. The highest volume-to-surface-area-ratio is achieved in a spherical design, A slope roof that has a less than 45 degree angle is closer to a sphere.

Do you have any real disadvantages of sloped roofs?

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