When purchasing an apartment, a garage or a commercial space in a building, you will encounter the term ‘basic deed’ at some point. What is this document and why is it so important? In this blogpost, we delve deeper into the significance and relevance of this basic deed for future owners and investors.

20 February 2025

Why do you need a basic deed?

When you buy a house, you take full ownership of the property. However, the situation is slightly different when you buy an apartment or garage in a building. You then buy part of a larger whole, sharing common areas such as the stairwell, lift, storage areas and garden with other owners. Commercial spaces in office buildings also fall under this system of joint ownership. Obviously, the entrance hall must be used jointly. But who may use the green area on the ground floor? And, consequently, who is responsible for its maintenance? To avoid misunderstandings, the law provides for a basic deed for the purchase and sale of a property in co-ownership.

Which information does this basic deed contain?

The basic deed is an official notarial deed. It describes the building in detail, with floor plans and technical details. The document clearly sets out which parts of the property are private and which are communal or shared. Co-owners also own a share of the communal areas. The size of your share depends on the value of your private property. Criteria such as location, purpose and net floor area also play a part in this. This valuation is documented by a notary, chartered surveyor, architect or estate agent and is included in the basic deed. Your share in the co-ownership also determines how much you must contribute to shared costs, including for the maintenance of the lift, the lighting in the corridor and the cleaning of the entrance hall. The greater your share, the higher your contribution. But your vote will also carry more weight during the meetings of co-owners as a result.

What to do when the basic deed contains errors

While a basic deed can be amended, this must be done before a notary public. So you can see why it is so crucial that the deed and its provisions are clear from the outset. The rule of thumb in the event of ambiguities or contradictions is that all parts that are used by more than one co-owner are communal. Sometimes, the basic deed will have to be amended. This is necessary, for example, when the division of shares of the communal areas changes. Such an amendment must be done by means of a new notarial deed, subject to the decision of the general meeting. Exceptionally, the justice of the peace can impose an amendment at a co-owner’s request.

Co-ownership regulations

Good agreements make good friends. Another important document, besides the basic deed, are the co-ownership regulations. Together, they constitute the ‘articles of association’ of the building in which you intend to live or rent out a unit. The co-ownership regulations lay down the rights and obligations of the co-owners. Owners may renovate their own bathroom, for example, when they see fit, but stricter rules apply for major changes that have an impact on the building’s exterior. It also includes clear agreements about the use of the communal areas and the division of shared costs. All these rules are laid down in the co-ownership regulations.

What about your tenant?

Want to rent out your property? In that case, you are responsible for informing your tenant about the provisions in the basic deed and the co-ownership regulations. After all, your tenant must also comply with these regulations. That is why you should always append these documents to the rental agreement. You can avoid lots of misunderstandings and discussions by communicating clearly from the outset about what is expected from everyone.

The difference with the deed of sale

The basic deed and the co-ownership regulations are essential documents when buying part of a larger building. You also need a deed of sale for the sale, which is signed before a notary. This contains additional information, such as:

The identity of the buyer and the seller respectively
The agreed price and payment terms
The intended use of the property (residential or commercial)
The date of signing
Information about urban planning obligations and the validity of mandatory documents and certificates.

Do you require further information? Want to schedule a meeting with our real estate advisor? Contact us.

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The basic deed: the key to a smooth purchase in a building