Renovating without a planning permit in 2026: when is an architect still required?

Flemish rules for renovation work changed significantly in 2026. Certain alterations to existing homes may no longer require an environmental permit, even if they affect structural stability. However, exemption from a permit does not automatically remove the requirement to appoint an architect. Since 5 September 2026, certain permit exemptions for structural work expressly require an architect to design and supervise the work.

Planning to remove a load-bearing wall, enlarge a window opening or extend your home? It is important to distinguish planning procedures from technical and professional obligations.

What changed in Flemish building regulations in 2026?

On 1 March 2026, an important reform of Flemish environmental-permit rules came into force. It simplified procedures for some building works. Several alterations that previously required notification may now be exempt from a permit, including, subject to conditions, certain works affecting the stability of an existing dwelling.

The changes caused uncertainty about when an architect must be appointed, so the rules were amended again. Since 5 September 2026, some structural works qualify for a permit exemption only if an architect is appointed for design and supervision. Administrative simplification does not remove technical responsibilities.

Permit-exempt, notification or permit-required: what is the difference?

Exempt works

Neither a permit application nor a notification is needed if every legal condition is met. Examples may include certain internal alterations, solar panels and specified facade or roof works. Local planning rules and heritage restrictions may still apply.

Notifiable works

A notification must be filed in advance through the Flemish Omgevingsloket. Since 1 March 2026, this procedure has been significantly restricted and generally concerns certain temporary planning activities.

Permit-required works

An environmental permit must be obtained before starting. Examples include building a new home and, generally since 1 March 2026, extending an existing dwelling with an attached structure.

Whether a permit is needed and whether an architect is compulsory are separate questions.

Removing a load-bearing wall: no permit, but an architect?

Removing a non-load-bearing partition

A wall without a load-bearing or stabilising function can generally be removed without a permit or mandatory architect. However, its structural role must be checked carefully: even a relatively thin wall can contribute to stability.

Removing a load-bearing wall

Removing a load-bearing or stabilising wall constitutes structural work. Following the 2026 reform, some such internal alterations may be exempt from a permit. To rely on that exemption, an architect must be appointed for the design and supervision of the works.

A structural engineer may also be needed. The assessment should consider existing loads, how they will be transferred, whether a steel beam or other support is necessary, the capacity of existing walls, columns and foundations, and temporary propping during construction.

An incorrect assessment can cause cracking, deformation or, in serious cases, structural instability.

Enlarging a window or creating a new opening

Replacing an existing window with a large sliding door or cutting a new facade opening can affect structural stability. Removing load-bearing masonry or installing a supporting beam is structural work.

Certain facade and roof works may be permit-exempt provided conditions are met, including no change to the physical building volume and no deterioration in energy performance. Where stability is affected, the exemption is conditional on appointing an architect for design and supervision. Local planning and heritage rules must also be checked.

Building a veranda or extension: pay attention to the new rules

Previously, certain extensions of up to 40 m² could be carried out under a simplified notification procedure. Since 1 March 2026, that notification route has been abolished for attached structures. An attached veranda, utility room or garage therefore generally requires a permit.

This does not mean an architect is automatically required for every extension. Exceptions exist for certain verandas, garages and carports, depending on their nature, dimensions, technical characteristics and legal conditions. A conventional extension of living space will generally require an architect.

What are the risks of renovating without proper guidance?

Structural damage

Removing a load-bearing wall or enlarging an opening changes how loads travel through the building. Cracks, deflection, settlement or distortion may occur, sometimes months or years later.

Liability and insurance

If structural works cause damage, the responsibilities of the owner, contractor and designers may be disputed. Insurance cover depends on the cause, policy wording and specific circumstances.

Planning and legal consequences

Works carried out without the required permit, or without meeting the conditions for an exemption, may constitute a planning infringement and lead to enforcement or penalties. Failure to comply with the architect requirement can have separate legal consequences.

Problems when selling

Undocumented alterations, such as removing a load-bearing wall, may raise concerns for future buyers. Missing plans, calculations or records can create uncertainty about safety and compliance.

What is the difference between an architect and a building expert?

An architect has legally defined design and supervision duties for certain building works. A structural engineer assesses the structure and performs necessary calculations. An independent building expert plays a different, complementary role: assessing the existing condition, identifying technical risks, inspecting workmanship and investigating defects.

HEXA Experts provides independent technical advice to homeowners before and during renovation work. A building expert does not replace an architect where one is legally required, or the calculations of a structural engineer.

Conclusion: no permit does not mean no obligations

Flemish rules were simplified in 2026, and some structural alterations may now be permit-exempt. Nevertheless, certain exempt structural works expressly require an architect for design and supervision. Every renovation must also be technically sound, regardless of its planning status. Assessing the existing structure and preparing properly can prevent serious problems.