Do I need a permit to build a garden shed, a veranda or a carport?

What is not allowed, what is required?

• Flanders: Freestanding outbuildings (shed, storeroom, greenhouse, carport) need no permit if together they are no more than 40 m², at most 3,5 m high and no more than 30 m from the house. In the side garden they must be at least 3 m from the boundary, in the back garden at least 1 m (in the back garden they may be built against an existing shared wall). Rainwater must stay on your own plot. In the front garden, you need a permit.
• Wallonia: A garden shed needs no permit if it is at most 20 m², 3,5 m high, at least 1 m from the boundary and there is only one per property. For a carport, the limit is at most 40 m² and 3,5 m high; there are other conditions too.
• Brussels: The area you can build without a permit is very small (e.g. at most 9 m² for a separate garden shed). Carports and verandas usually need a permit. Ask the municipality for the exact limits.
• Flanders: Since 1 March 2026, a veranda attached to the house needs a building permit. Before, a notification was enough; this is no longer the case.
• The exemption only applies if all conditions are met together; the municipality's zoning plan can forbid outbuildings.

Penalty and indirect consequences

Why does this rule exist?

An outbuilding affects the neighbour's sunlight, privacy and view; the permit process gives neighbours the right to object. Keeping gardens permeable lets rainwater soak into the ground and reduces the risk of flooding.