The new provisions refer to “three types” of rights to build: (i) the autonomous right to build, (ii) the perpetual right to build allowing the creation of property in volume and (iii) the accessory right to build (super cie-conséquence / accessoir opstalrecht). We will discuss the concept of property in volume later.
The right to build is de ned as “the in rem right of use which confers the ownership of the volumes, built or not, in whole or in part, on, above or below the land of someone else, for the purpose of having constructions or plantations thereon”. This de nition emphasizes the notion of volume and con rms that the purpose of the right to build is to proceed to a horizontal, temporary split of ownership.
Purpose of the right to build
The right to build relates to a volume located on, above or below the land of a third party. Buildings located in this volume or to be built in this volume are not the object of the right to build and shall be held in full ownership by the holder of the right to build for the duration of his right.
The new provisions relating to the right to build introduce a special feature in case the right to build is related to a built volume (i.e. a volume with existing buildings). The law now indeed provides that in case a right to build is granted on a built volume, there is a “contractual acquisition of the existing buildings” by the holder of the right to build. Consequently, the holder of the right to build becomes the owner of such buildings and shall therefore bear all charges, taxes and expenses, including maintenance and repairs, relating thereto.
Duration of a right to build and payment compensation
Except in case the right to build is granted on public domain properties or in the context of property in volume, the right to build is a temporary right, with no minimum duration, but with a maximum duration which is now 99 years.
As under the Act of 1824 on rights to build, the ownership of buildings acquired or built during the term of the right to build reverts to the owner of the land by accession upon expiry of the right. As consideration for these buildings, the owner of the land must pay a compensation to the holder of the right to build.
“Book 3 introduces the notion of ‘volume located on, above or below the land’ “
Accessory right to build
The new Book 3 also recognizes the concept of the accessory right to build. The accessory right to build arises from a right of use, i.e. an in rem right of use (a long-term lease right, a usufruct right or an easement), a personal right (e.g. a lease) or an administrative right (e.g. a concession right) pursuant to which its holder is authorised to build. Thanks to its accessory right to build, the holder of the underlying right will be the owner of the constructions and plantations that he himself has built during the term of his underlying right.
The accessory right to build is intrinsically linked to the underlying right of use, both in terms of its duration and its ( nancial) consequences at the end of the right, although the principle of the owner’s right of accession at the end of the underlying right remains.
An important consequence of the accessory nature of this right to build is that this and the constructions built under the accessory right to build cannot be “detached” from the main right, which means that any assignment or mortgage requires the assignment or mortgage of the main right - with one major exception in case the main right is an administrative right (e.g. concession right), which cannot be mortgaged.In the latter case, vesting a mortgage on the accessory right to build and the constructions built by the holder of the administrative right (e.g. concessionaire) remains authorized.
