Survey of saddle roof knee wall height

To loosen up this "window sheath," there are window arrangements that combine both a knee wall window reaching down to the floor and a roof window. One line then remains of course, the windowsill is omitted.

The hermaphroditic kinked windows were such a short-lived fashion phenomenon in the early 80s that they never even had their christening and have remained a nameless phenomenon. Even the 45° corners in floor plans lasted considerably longer. As a window manufacturer, I was relieved in terms of installation warranty that I only entered the industry after this short fashion was long over. Although we were strong in roof windows, we never acquired projects with these hermaphrodites as modernization customers.

The appearance of the room can also be influenced by boxing in, e.g. storage space or built-in furniture.

Built-in furniture is good, but classic knee wall spaces are, from an insulation standpoint, I would say "not nice". Therefore, I advise extremely sparing use of consecutive arrangements of knee walls and knee wall gable, at most in the area of WC and shower (as long as the bathroom is not located in a cross gable).

In some development plans, it is possible to expand a room through dormers. Then it depends on the described length and width ratios.

Thanks to contemporaries who push regulations to the very limit, most municipalities now counteract with such strict exceptions that often only real dormers instead of at least cross dormers are possible. With knee wall roof trusses, however, real dormers are "death on a bucket," as one of my mentors would have said.

but classic knee walls in terms of insulation, I would say "not nice".

The knee walls in the parental home were "insulated". Isn't that classic? What's not nice about it?

That's why I advise using connections of knee walls and dwarf walls very sparingly, at most in the area of the toilet and shower (as long as the bathroom is not located in a cross gable).

If done properly, there is no reason not to do it.

If done correctly, there is no reason not to do it.

Cavities are to be avoided and are actually almost always beneficial from a building physics perspective:

The knee walls in the parent house were "insulated." Isn't that classic? What's not nice about that?

Traditionally, one built without a knee wall with sloped ceiling sections behind the dwarf walls. The dwarf walls were insulated afterwards (or, in a transitional phase between the dwarf wall and knee wall era, already during construction). According to today's insulation standards, the boundary of the "thermal envelope" then only extended down to the dwarf wall under the rafters, then abutted the dwarf walls and continued on the floor of the sloped ceiling area (i.e., on the floor slab). Three "sections" of insulation flow—this is technically "not nice" and, in my opinion, even more important than the gain in usable space as a reason for the trend to replace the dwarf wall with the knee wall.

That would be a two-story building. Unfortunately, and this probably concerns you, the plots are getting smaller, so the floor area ratio restricts builders to such an extent that the roof slopes cannot be compensated by the footprint. Therefore, you have to raise the knee wall to gain the necessary square meters, even if it is only feasible through actual headroom clearance.

To be honest, we don’t have such a small plot (700 sqm) and 180 sqm of pure living space + additional storage space. We simply like the spacious look.

We simply like the spacious appearance.

What is more spacious about a 180 sqm two-story house compared to a 180 sqm gable roof house?

What is more spacious about a 180 sqm two-story house than a 180 sqm gable roof house?

It looks more massive from the outside and one has to like that.