The BAG (Basisregistratie Adressen en Gebouwen) calculates according to the NEN2580 measurement instruction. These are the ground rules for measuring homes that realtors and appraisers, among others, also calculate with. This explains exactly how to calculate the area of your home and that of other spaces such as garages, sheds, balconies, basements, etc.
The “measurement instruction” includes terms such as living area, building-related outdoor space (balconies/roof terraces), external storage space (a storage shed/shed that is not attached to the house) and other indoor space (including an attached storage room or garage).
The area that counts in the BAG is the living area + other indoor space combined. Other indoor space in most cases are garages and storage rooms that sit against the house.
Now there is something crazy about how the BAG when it comes to handling the “ground rules” about measurement. And specifically when it comes to garages or storage rooms that are attached to the house. Indeed, built against the house, according to the official nen2580 measurement instructions, simply means “other indoor space. Thereby, it does not matter whether you can reach that storage/garage inside (through the main house) or outside.
The crazy thing is that the way the BAG measures looks at it differently. An attached garage or storage shed counts SOMS WELL and SOMS NOT in the BAG area.
Because the BAG practice manual is impossible for anyone to understand, here we explain to you simply and visually when your attached garage/shed or outbuilding does or does not count toward the BAG area. We do this by outlining 4 situations. Note: In the examples below, a ‘Garage’ is the same as a ‘Storage’.
Situation 1: The house and garage were built at the same time:
The house and garage were built at the same time. So we say “they came about at the same time. Thus, the garage was part of the original building plan and was not added later. The garage also belongs 100% to the house. So it is not that 1 part of the garage belongs to the neighbor’s house. It is irrelevant here now whether you can access the garage from the inside and/or outside.
The area of the garage COUNT HERE for the BAG area.
Situation 2: The garage was built later with the house and is NOT accessible from inside:
The garage was later built with the house. After all, the house is from construction year 2000 and the garage is from construction year 2022. The garage is also not accessible from inside. In this case, the area of the garage DOES NOT COUNT for the area of the BAG.
Note that if the garage had been accessible from inside (through the house), the area of the garage would have counted for the BAG. In the following example, we show that.
Situation 3: The garage was built later to the house and is WELL accessible from inside:
The garage was later built with the house. After all, the house is from construction year 2000 and the garage is from construction year 2022. The garage is WELL accessible internally. In this case, the area of the garage DOES COUNT for the area of the BAG.
This is because the garage is accessible from inside. Note that if the garage was not accessible from the inside at first, but you make it accessible from the inside at a later time, it will also count in area for the BAG from then on.
Situation 4: A home has a detached garage (regardless of when the garage was built):
In both cases above, the area of the garage does NOT count toward the BAG area of the house because it is completely separate from the house.
Calculate living area
Do you also want to learn how to calculate the official living area at a property, what about building-related outdoor space, external storage space, conservatories and more? Then watch this video: