Renting cellars and attics in Belgium: what the law says

What is legal (and what is not)

Renting cellars and attics is a topic that comes up regularly, especially in large cities where space is scarce. Let us clarify from the outset:

Renting a damp and dark cellar as a bedroom is illegal and exposes the landlord to criminal sanctions (endangering lives) and administrative penalties (planning). The conformity obligation applies to all housing.

Renting as storage space

This is the most common and simplest use. Renting a cellar or attic as storage space is perfectly legal and requires neither planning permission nor an EPC.

The rules:

• General law lease (not a primary residence lease)
• Duration and notice period freely agreed in the contract
• Registration recommended but not mandatory (except for leases > 3 years)
• No habitability standards to meet (it is storage, not housing)

Clauses to include:

• Permitted use: storage only, no habitation
• List of prohibited goods: flammable, explosive, perishable items
• Access conditions: hours, keys, security
• Liability: the landlord guarantees watertightness and structural safety

Rent is generally modest: 30 to 80 EUR/month for a cellar of 5-15 m2 in Brussels.

Conversion into housing: the conditions

Converting a cellar or attic into housing is possible but strictly regulated:

Planning permission required

A change of use (storage to housing) requires planning permission in all three regions. The application must demonstrate:

• Plans of the proposed conversion (architect required)
• Compliance with the sector plan and regional planning regulations
• Adherence to habitability standards

Habitability standards

Conversion cost

The average cost of converting an attic into housing is 800 to 1,500 EUR/m2 (insulation, windows, electricity, staircase, finishes). For a cellar, it is higher (damp treatment, possible excavation): 1,200 to 2,000 EUR/m2.

After conversion, the housing must obtain an EPC certificate and comply with the energy standards in force.

Co-ownership and regulations

If the cellar or attic is part of a co-owned building, the co-ownership regulations may prohibit or limit renting:

• Check whether the cellars are private lots (separate lot) or common areas with private use
• If common areas: renting requires approval from the general assembly
• If private lots: renting is possible unless the regulations say otherwise
• Conversion into housing almost always requires co-ownership approval (change of use)

Taxation and insurance

Taxation:

• If the tenant is a natural person: taxed on the indexed cadastral income (often very low for a cellar)
• If the tenant is a company: taxed on the actual rent
• Property tax: included in the building’s cadastral income or separate if a distinct lot

Insurance:

• The landlord must verify that their fire insurance covers the rented spaces
• The tenant must take out contents insurance for their stored goods
• In case of water damage in a cellar, liability depends on the cause (structural = landlord, contents = tenant)

The taxation of rental income applies in the same way as for standard housing.

Practical advice

1. Clearly define the use: storage only, no habitation
2. Draft a written contract under general law with use, duration, rent and notice period
3. Explicitly prohibit habitation and storage of hazardous materials
4. Check the insurance on the building and require contents insurance from the tenant
5. Do not convert without permission: planning inspections are frequent in large cities
6. Consult the co-ownership regulations before renting a common area with private use

Renting a cellar or attic is a modest but hassle-free income supplement. For your housing properties, use our online lease creation tool. And for a full overview of your obligations, see our landlord’s guide.