Living Space Calculation under the WoFlV — Rules and Weighting

What the Living Space Ordinance governs

The German Living Space Ordinance (Wohnflächenverordnung, WoFlV) has been in force since 1 January 2004 and replaced the corresponding provisions of the Second Calculation Ordinance. It answers three questions: which rooms belong to the living space, how their floor area is determined, and what proportion of it enters the result. [§ 1 WoFlV] For calculations produced up to the end of 2003 under the Second Calculation Ordinance, that earlier calculation continues to apply. [§ 5 WoFlV]

The WoFlV is mandatory for publicly subsidised housing. In practice it has become the general benchmark far beyond that: banks, valuers and courts regularly fall back on it where nothing else has been agreed. Anyone who needs to evidence a living space figure for financing, sale or letting therefore calculates under the WoFlV in case of doubt.

Which rooms form part of the living space

The living space comprises the floor areas of the rooms that belong exclusively to the dwelling in question. [§ 2 (1) WoFlV] Explicitly not included are: [§ 2 (3) WoFlV]

• Ancillary rooms, in particular cellars, laundry rooms, drying rooms, boiler rooms, attic storage, garages as well as storage and cellar-substitute rooms outside the dwelling
• Rooms that do not meet the building law requirements for their intended use
• Commercial premises

The second point is the one most often overlooked in practice. A converted hobby room in the cellar, or a loft room lacking the required clear height, adequate daylight or a second escape route, is not a habitable room within the meaning of the state building code — and therefore not living space either, however high the standard of the fit-out.

How the floor area is determined

Measurements are taken as clear internal dimensions between building elements, starting from the front edge of the finish — that is, in the completed state, not from shell dimensions. [§ 3 (1) WoFlV] As to what is deducted and what is not:

The logic behind this: whatever can be removed or replaced does not reduce the living space. The area beneath the bathtub counts, because the tub can be taken out one day. A structural pier does not count, because it permanently occupies space.

What proportion of each area is counted

Not every floor area determined enters the living space in full. The WoFlV grades the weighting:

The grading by clear height has its greatest effect in the loft — there the countable living space departs considerably from the plain floor area. How that is calculated in detail is set out on the page Sloping ceilings and living space.

For conservatories, swimming pools and similar rooms enclosed on all sides, heatability is what decides: the ordinance only provides for halving in the case of unheatable rooms of this kind. If they can be heated, nothing special applies — they are counted according to their clear height like any other room.

For balconies the standard case is one quarter. Applying up to one half is the exception and presupposes a correspondingly high quality of the space. Anyone applying the higher figure without reasoning risks the calculation not standing up to scrutiny.

Common sources of error in practice

• Developer figures adopted unchecked. Brochure areas from the construction phase frequently deviate from the as-built situation, because changes were still made during construction.
• Calculated under DIN 277 and presented as living space. The figure then comes out systematically too high — see WoFlV or DIN 277.
• Balcony counted in full. A common error in older brochures that considerably overstates the area.
• Outdoor areas added without limit. The ordinance governs the proportion at which terraces and balconies are counted, but not the ratio they may bear to the dwelling. Purely arithmetically, a bungalow with 100 m² of living space could have an equally large terrace counted in proportion — which is not appropriate. In practice it has become established to add outdoor areas only up to around 10 %, in exceptional cases 15 %, of the living space.
• Cellar counted because it is converted. The state of the fit-out does not change its classification as an ancillary room.
• Shell dimensions taken from the construction drawing. Determining the area from a drawing is permissible [§ 3 (4) WoFlV], but drawings are as a rule dimensioned in shell measurements. What counts for the living space is the actual clear space between the finished wall surfaces. For plaster, facings and other wall build-ups, 3 to 5 % is therefore customarily deducted depending on the construction — omitting this overstates the living space.

Why the figure needs to hold up

The living space is the reference figure for purchase price, rent, apportionment of service charges and mortgage lending value. A deviation from the actual area can therefore have immediate financial consequences — in a tenancy just as much as on a sale. There is no statutory tolerance.

What matters is therefore less the bare figure than its traceability: a documented survey, a room-by-room schedule, and a clear statement of which rules were applied and on what basis.

Frequently asked questions