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FLOOR AREA RATIO: (ALSO) RELEVANT WHEN SELLING A PROPERTY
The floor area ratio (GFZ) is relevant above all when buying and selling a plot, but it can also play a role when selling a property. Put simply, it is one of the values that help answer the following question: how many square metres may an existing or planned building on a plot have – across all storeys?
THE GFZ FORMULA IS QUITE SIMPLE
The legal basis for the floor area ratio is Section 20 of the German Land Use Ordinance (BauNVO). According to the BauNVO, the GFZ determines how many square metres of floor area are permitted per square metre of plot area. The competent building authority sets the GFZ in the development plan. Rules for the building to be erected follow from it. An example:
If a floor area ratio of 0.5 has been set, a building with a maximum floor area of 500 square metres (1,000 x 0.5) may be built on a previously undeveloped plot of 1,000 square metres. When determining the total floor area, the external dimensions of the building are decisive.
So the formula is: "floor area ratio x plot size = maximum possible total floor area". The floor area of a building is obtained by adding up the areas of the individual full storeys. What exactly counts as a full storey is in turn defined differently in the building regulations of the federal states. The Bavarian building regulations, for example, define a full storey as an above-ground storey with a clear height of at least 2.40 metres, among other things.
The floor area ratio and the size of the plot have an immense effect on the possible size of the building. Taking the example above again, with a floor area of up to 500 square metres from a ratio of 0.5 and a 1,000-square-metre plot:
Here, among other things, a four-storey house with 125 square metres per floor or a five-storey house with 100 square metres per floor would be possible. However, the maximum possible number of storeys depends on further regulations.
VALUES SUCH AS THE GFZ ARE INTENDED TO PREVENT OVERDEVELOPMENT
When a property is sold, the GFZ is particularly relevant if the property for sale is larger than the maximum total floor area calculated on the basis of the ratio, if the house changing hands is to be extended, or if the buyer wants to demolish the house on offer in order to build a completely new house on the plot.
So it is by no means unimportant when selling a property either. The floor area ratio can affect the selling price because it influences the value of the plot. In principle, a plot is worth more if it offers possibilities for many different kinds of development.
This of course applies even if there is already a building on the plot. After all – at least in theory – demolition and new construction would still be possible at any time after the sale. And the higher the floor area ratio and the site occupancy index, the more the size of the new building can vary. This tends to increase the price.