11ant
2017-09-09 12:11:24
- #1
It seems to me that the confusion of the OP simply results from not distinguishing between two fundamental types of stairs:
Stairs going (up and) down
(meaning where there is no flat floor surface under the stairs, but another staircase instead) are not part of the living area because they are purely functional components. Therefore, neither their top surface area nor the floor area they cover is counted towards the living area.
Stairs going only up
(meaning where there is a flat floor surface under the stairs) accordingly offer an area beneath them whose usability for residential purposes increases with height. Logically, the calculation method applied here treats the slope of the underside of the stairs as the slope of a roof underside – after all, standing height is standing height, whether under a staircase or a roof slope. Therefore, up to 2 m height it is counted proportionally, and under 1 m it is considered unusable.
Stairs with very few risers
have a subordinate functional significance; here the design aspect of structuring the room usually predominates – e.g., to delineate the seating area from the dining area. This often happens with steps that extend over even the entire width of the room, not just the walking width. Flower boxes stand on them or firewood is stored there. Consequently, the top surface areas of such "stairs" are not deducted from the living area. If the relevant floor is itself on an even floor level and the stepping is one floor above, the room heights of the floor are naturally different as a result. With fewer than three risers, however, this will not lower the lower area below 2 m in height, so it remains 100% countable and consequently such a "stair" is irrelevant even then. Hence this "trivial rule" for stairs with very few risers. For stairs with more than three risers in total, this naturally does not lead to any different weighting of their first three risers.
For the OP this results in:
1. The under-three-risers rule does not apply to his stairs.
2. The space under his stairs is – because it is flat below and sloped above – to be calculated according to attic standards, i.e., not counted up to 1 m height, counted half between 1 m and 2 m height, and fully counted above 2 m height.
Stairs going (up and) down
(meaning where there is no flat floor surface under the stairs, but another staircase instead) are not part of the living area because they are purely functional components. Therefore, neither their top surface area nor the floor area they cover is counted towards the living area.
Stairs going only up
(meaning where there is a flat floor surface under the stairs) accordingly offer an area beneath them whose usability for residential purposes increases with height. Logically, the calculation method applied here treats the slope of the underside of the stairs as the slope of a roof underside – after all, standing height is standing height, whether under a staircase or a roof slope. Therefore, up to 2 m height it is counted proportionally, and under 1 m it is considered unusable.
Stairs with very few risers
have a subordinate functional significance; here the design aspect of structuring the room usually predominates – e.g., to delineate the seating area from the dining area. This often happens with steps that extend over even the entire width of the room, not just the walking width. Flower boxes stand on them or firewood is stored there. Consequently, the top surface areas of such "stairs" are not deducted from the living area. If the relevant floor is itself on an even floor level and the stepping is one floor above, the room heights of the floor are naturally different as a result. With fewer than three risers, however, this will not lower the lower area below 2 m in height, so it remains 100% countable and consequently such a "stair" is irrelevant even then. Hence this "trivial rule" for stairs with very few risers. For stairs with more than three risers in total, this naturally does not lead to any different weighting of their first three risers.
For the OP this results in:
1. The under-three-risers rule does not apply to his stairs.
2. The space under his stairs is – because it is flat below and sloped above – to be calculated according to attic standards, i.e., not counted up to 1 m height, counted half between 1 m and 2 m height, and fully counted above 2 m height.