ᐅ Which Roof Style Is Best for a Challenging Building Layout?
Created on: 21 Dec 2025 21:09
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Bauherrin2024
Hello everyone,
Our plot (Bavaria) has a very restrictive development plan from 1981. It allows a pitched roof with dormers (I+D), no knee wall, no dormers, gable or hip roof, with a pitch of 18-35°. We recently had a pre-consultation with the building authority and submitted a preliminary inquiry. The following was proposed:
Two full stories, maximum eaves height 6 m (20 feet), gable, hip, or flat roof.
BUT: maximum roof pitch 10 degrees. (I had requested 18 degrees, which would not have required a special exemption.)
Alternatively:
Still pitched roof with dormers (I+D), knee wall max. 1 m (3.3 feet), then the roof pitch can be increased to 42 degrees.
I understand that they want to limit the maximum building height. At first, I was very happy that they would actually approve two full stories, as I would prefer to avoid roof slopes. But the more I read, the more disappointed I become. A gable or hip roof with a 10-degree pitch doesn’t seem like such a great idea, both stylistically and because it would require an expensive, watertight subroof construction. We would least prefer a flat roof because we imagine a “nice, warm house with red tiles and yellow facade color.” At most, a flat roof with 10 degrees (which would be more like a single-pitch roof?) combined with tiles and roof overhang.
I am really confused. Could you share your thoughts on this? If anything is unclear, feel free to ask :-) Many thanks!!
Our plot (Bavaria) has a very restrictive development plan from 1981. It allows a pitched roof with dormers (I+D), no knee wall, no dormers, gable or hip roof, with a pitch of 18-35°. We recently had a pre-consultation with the building authority and submitted a preliminary inquiry. The following was proposed:
Two full stories, maximum eaves height 6 m (20 feet), gable, hip, or flat roof.
BUT: maximum roof pitch 10 degrees. (I had requested 18 degrees, which would not have required a special exemption.)
Alternatively:
Still pitched roof with dormers (I+D), knee wall max. 1 m (3.3 feet), then the roof pitch can be increased to 42 degrees.
I understand that they want to limit the maximum building height. At first, I was very happy that they would actually approve two full stories, as I would prefer to avoid roof slopes. But the more I read, the more disappointed I become. A gable or hip roof with a 10-degree pitch doesn’t seem like such a great idea, both stylistically and because it would require an expensive, watertight subroof construction. We would least prefer a flat roof because we imagine a “nice, warm house with red tiles and yellow facade color.” At most, a flat roof with 10 degrees (which would be more like a single-pitch roof?) combined with tiles and roof overhang.
I am really confused. Could you share your thoughts on this? If anything is unclear, feel free to ask :-) Many thanks!!
Bauherrin2024 schrieb:
Of course, we have an architect.But probably one in quotation marks, basically a puppet of the general contractor, otherwise these questions wouldn’t even come up.https://www.instagram.com/11antgmxde/
https://www.linkedin.com/company/bauen-jetzt/
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Bauherrin202422 Dec 2025 15:3911ant schrieb:
But probably one with quotation marks, aka the general contractor’s draftsman, otherwise these questions wouldn’t come up.11ant schrieb:
But probably one with quotation marks, aka the general contractor’s draftsman, otherwise these questions wouldn’t come up.No, but I will let him know that a forum lackey thinks he is doing a poor job while he is on vacation :-)Papierturm schrieb:
Knee wall heights between 1 and 2.2 meters (3.3 and 7.2 feet) are the "zone" to avoid. Depending on a person’s height, decent windows are not possible there. Either go up to a maximum of 1 meter (preferably a bit less, which is why I suggested a knee wall height around 75 cm (30 inches)) or start from 2.3 meters (7.5 feet) upwards. In between, you won’t get nice windows. ypg schrieb:
For a gable roof with a low knee wall, dormers are a good option. The higher the knee wall, the more "not feasible," some users on this forum say. Some install continuous strip windows under the roof at knee wall heights of about 2 meters (6.6 feet). That might be sufficient for bathrooms or secondary rooms but usually doesn’t allow for a good outward view, so it’s less suitable for living spaces.
In my opinion, however, you can also install attractive dormers at knee wall heights of around 1.6 meters (5.3 feet). The height of the knee wall is a crucial factor for window design because the trend of "pivoting windows" (which I can understand from my experience as a former window manufacturer) has not become established: building a combined element of a façade window and a roof window is highly complex. Such a unit "moves" in too many dimensions and is therefore very difficult to seal properly. Installing it requires, in principle, watchmakers, piano tuners, or other highly skilled and expensive precision technicians. It’s better to choose either façade windows or roof windows on the eaves side—possibly also façade windows that extend over the knee wall via a dormer. If such a roof structure is not allowed and you must use façade or roof windows limited by the knee wall, then you face restricting factors like ring beams, roller shutter boxes, collar beams (usually at the height of the purlins), and similar elements. This makes the top edge of the knee wall a sort of thick beam acting as a practical boundary line. The only options then are to look over it, under it, or against it.
This results in effective knee wall heights of about 120 cm ± 20 cm (about 100 to 140 cm, or 39 to 55 inches). At a knee wall height of 2 meters (6.6 feet), roof windows essentially become skylights: they provide daylight and a view of the sky, but no panoramic view. You won’t see much more than clouds under the roof edge.
A knee wall height of 2.2 meters (7.2 feet) or more looks "forbidden" from the inside, as it feels more like a truncation of the ceiling than a reduction of the eaves wall height (which, from a layperson’s perspective, is usually the goal). Therefore, regarding knee wall height, the idea that "more is better" is mistaken, and maximizing the knee wall is an unsuitable strategy.
Bauherrin2024 schrieb:
No, but I will tell him that a forum member thinks he is doing a bad job while he’s on vacation 🙂 He is doing a poor job—that is a fact. Whether because he is a subordinate of a general contractor or a freelance architect without cause is irrelevant. I already explained simply and objectively how to properly determine when a top floor counts as an attic or as a full upper floor under the roof. Depending on which applies, the two mentioned building design concepts cannot both be valid at the same time. Either his design approach leaves much to be desired or you two have communication problems. This is not a philosophical matter (you spoke of seeking a second opinion as your motivation). Your space requirements "downstairs" and "upstairs" are either nearly equal ("urban villa") or different ("one-and-a-half-story house"). Gender-fluid houses do not exist in this sense. A performance phase 2 still in progress is not a good time for a planner to go on vacation.
https://www.instagram.com/11antgmxde/
https://www.linkedin.com/company/bauen-jetzt/
11ant schrieb:
Window with Bend 11ant schrieb:
when combining a facade window and a roof window element None of us are talking about roof windows or windows with bends.
ypg schrieb:
None of us are talking about roof windows or windows with bends.Both @Papierturm and you referred to the relationship between knee wall height and the suitability of the possible windows for looking outside. I then explained in more detail which of the four window types are possible or practical under which conditions:1. Windows only in the roof surface >> the higher the knee wall, the less comfortable it is to have a view while sitting;
2. Windows only in the knee wall >> the lower the knee wall, the more only children and small animals enjoy their view;
3. Windows in both, with a knee wall-breaking element (dormer) >> unproblematic, but often restricted by zoning regulations; and
4. Windows in both, without a dormer >> then the window itself must have a knee-bend, which for the reasons mentioned has never really become a popular solution from a construction standpoint.
The conclusion remains not to try to maximize the knee wall height, but to accept the characteristics of roof windows versus classic vertical facade windows and choose between them.
The height of the knee wall sets a limit for yourself. That limit becomes "a beam in the view," and you have to decide whether you want to maximize the height (consequence for the view: high jump) or keep it moderate (consequence for the view: limbo). Without a construction that bridges over the knee wall, you can combine looking over and under, but you still have the eave height as a beam in the view.
https://www.instagram.com/11antgmxde/
https://www.linkedin.com/company/bauen-jetzt/
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