ᐅ What is the ideal knee wall height?

Hello,

I am interested in your opinions or thoughts about knee wall height. We technically wouldn't need one and could build two full stories, but from an exterior design perspective, I find a certain knee wall height more aesthetically pleasing. The question is how high it should be so that it doesn’t significantly reduce usable space. For example, I was thinking of a height that would still allow placing a desk or a bathtub underneath.

Another aspect is that, unlike a full story, knee walls typically require skylights or roof windows. Is this significantly more expensive, or does it roughly balance out since a knee wall uses less material compared to two full stories?

Thank you for your thoughts.

Hello,
we have a knee wall height of 1.60 m (5 feet 3 inches) and have had good experiences with it. Even tall individuals do not find their freedom of movement too restricted. Our bathtub is also located beneath the knee wall, and we have had no issues with that either. The slope is still steep enough to create a cozy atmosphere.

Regarding skylights: we decided against them and instead have a dormer on one side of the house with floor-to-ceiling windows. On the other side (children’s room and bathroom), we actually have knee wall windows. I think they look great in the children’s room, but in the bathroom the height is rather inconvenient. We have white, non-transparent pleated blinds installed there. Another advantage: you can look outside while lying in the bathtub.

The knee wall height functions as a window boundary, see:

11ant schrieb:

The knee wall practically serves as a window boundary, which is why "ideal" knee wall heights are around 100 120 plus or minus 20. See also (externally) "How the knee wall affects the window design in the attic."

11ant schrieb:

Simply put, you can visualize the knee wall, with the eaves height acting as the knee joint. Facade windows at the eaves sides only extend into the lower sections (the "lower thigh") and, considering elements such as the sole plate, ring beam, and possibly a roller shutter box, offer views only suitable for crawling children and small dogs. In the upper sections (the "upper thigh"), there are only roof windows, which, if the knee wall is built too high, become sky-facing windows. There are only two ways to break through this window boundary: either dormers (commonly grouped under the general term "dormers" in everyday use), though their proportion relative to the eaves length is usually limited, or windows that follow the wall-roof transition angle (which are difficult to design and install, and generally available only in premium builder ranges).

By the way, several of my posts on the topic of knee wall height are still quite recent, ranking near the top in the forum search. As long as the local development plan allows it, I am a big fan of mansard roofs.

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Thank you, 11ant. I will take a look through your posts. Hmm, according to the development plan, we are limited to gable roofs.

If anyone has any further thoughts, I would greatly appreciate them. Many thanks, Bubo bubo, for yours.

Best regards

UnfähigerBeamt schrieb:

The question is just how high,

The question is about the roof pitch.
We have a kneewall height of 125cm (49 inches), resulting in a knee wall thickness of about 132cm (52 inches). With a roof pitch of around 26 degrees, this works out just fine.
A roof window is planned along the 10-meter (33-foot) length of the house in the dressing area. In front of the knee wall, there is space for Malm-style chests of drawers with four drawers, and you can also comfortably place items like vases or photos on top. So, a desk or vanity table would also be possible.
Our bed fits well under the sloped ceiling with a high headboard, allowing us to sit up comfortably. A bathtub would also be feasible.
With our roof pitch, I would recommend increasing the wall height by one brick, about 25cm (10 inches), to gain a bit more room.
If the roof pitch is 40 degrees or steeper, then the 125cm (49 inches) height would definitely be sufficient.
I would definitely plan and build with sloped ceilings again because the rooms feel cozier, and the gables look more attractive.

UnfähigerBeamt schrieb:

Thank you, 11ant. I will take a look at your posts. Hmm, according to the development plan, we are limited to gable roofs.

I answered your question earlier here as academically and universally as you posed it. If it actually applies specifically to the project in https://www.hausbau-forum.de/threads/firstrichtung-parallel-zur-strasse-od-90-grad-winkel.48261/, then the answer might be different, but for that we would need a clearer understanding of your plans than what has been shown there so far (which is still not detailed enough to make a firm judgment).

UnfähigerBeamt schrieb:

I attached a sketch I drew myself and in the area circled in green, I’m not sure how to arrange the window areas. Behind that will be the bedroom. I also attached another picture as inspiration. It can’t be implemented 1:1 since our house has different dimensions (it’s larger).

… however, this makes me fear that you might be tackling the problem from the wrong end quite intensively (or rather, the animal in question might still not be quite clear – whether it’s actually a cow that’s coming out of this).

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https://www.linkedin.com/company/bauen-jetzt/