Dormer on the rear — usually permit-free

What falls under 'rear roof surface'?

The rear roof surface is the roof surface facing away from the public road — so the rear garden side. In the regulations, a side roof surface facing the rear yard area also counts as a rear roof surface. This is convenient for a corner house: if the side facade faces your own rear garden, you may also build permit-free there under the same conditions.

Are you in doubt about the classification of a roof surface (especially with pitched roofs or corner houses)? Check with the municipality or via the Omgevingsloket.

The conditions for a rear roof surface

The conditions are identical to the general permit-free scheme (Bbl annex II, art. 2 sub 4):

• A minimum of 0,5 metres above the roof base (lowest point of the roof surface).
• A minimum of 0,5 metres below the roof ridge.
• A minimum of 0,5 metres from the sides of the roof surface.
• Maximum height 1,75 metres (roof base of the dormer to the top).
• No roof terrace or balcony on top.
• The building is not a monument and is not located in a protected cityscape.

Do you meet all these points? Then you can generally build without an environmental planning permit. Do you fall just short? Then you must submit an application.

When does the rear still require planning permission?

A dormer on the rear can still require a permit if:

• The building has a monument status (national or municipal).
• The building falls within a protected city or villagescape.
• The municipality imposes specific restrictions in the environmental plan (for example, in new housing estates with an aesthetic quality plan).
• Your dormer does not meet one of the dimensions.
• The building is an outbuilding or commercial property.

Moreover: even if no environmental planning permit for a building activity is needed, an environmental planning permit for an environmental plan activity may be required if the municipality has established stricter rules. Always check this.

Practical points of attention

• Neighbour law (art. 5:50 BW): windows within 2 metres of the plot boundary that provide a view of the neighbouring plot are only allowed with permission from the neighbours or if they are opaque and non-opening. A dormer with a side window within 2 m of the plot boundary falls under this.
• Structural engineer: you often need a calculation for the trimmer construction (even without a permit requirement, this is standard for the contractor / insurer).
• Insurance: report the renovation to your home insurance provider; some policies require a notification.
• Mortgage: for major interventions, your mortgage lender may set requirements — usually not for a standard dormer.

Checklist before starting

1. Complete the Permit check (Vergunningcheck) at the Omgevingsloket — print or save the confirmation. 2. Consult the local environmental plan via Ruimtelijkeplannen.nl or the municipality. 3. When in doubt: request written confirmation from the municipality (e.g. by email from the building counter). 4. Inform neighbours — not mandatory for permit-free building, but sensible (views, construction noise nuisance, possible shadow). 5. Archive structural calculations and execution documents — handy for a later sale.

Frequently asked questions

Short, honest answers to frequently asked questions.

Do I need to ask my neighbours for permission?

Not for the permit (since there isn't one). However, if your window is within 2 m of the plot boundary and provides a view of their plot, art. 5:50 BW requires permission or an opaque finish.

How do I prove later that it was permit-free?

Keep the results of the Permit check, before and after photos, drawings and the structural calculation. Upon a sale, the notary often asks for this.

Can I make the dormer wider than the 'standard' size?

The Bbl does not state a maximum width nationally, but municipalities can set a local limit. For very wide dormers, a preliminary consultation is sensible.

Does this also apply to an apartment with a roof floor?

Only if you are the owner of the roof surface and no HOA (VvE) stands in the way. In practice, an HOA always requires permission for changes to the roof.

What if the municipality enforces anyway?

If you can prove you are building within the Bbl, enforcement is difficult. When in doubt: submit your explanation and the Permit check confirmation in writing and request a formal decision.

Do I add up two dormers in a row?

Two separate dormers on the same roof surface must each individually meet the distance requirements. The space in between is not grounds for an exemption.

Are PV (solar panels) allowed on the dormer?

Yes, solar panels are themselves permit-free provided they lie flat on the roof surface. Combining them with a permit-free dormer is not a problem.

Does permit-free also apply to a flat roof dormer or a pitched roof dormer?

The Bbl rules mention dormer as a type, regardless of the sub-variant. Shape (flat, pitched, curved) does not matter, provided the dimensions are correct.

What is the influence of an aesthetic quality plan?

An aesthetic quality plan can impose additional requirements via the environmental plan, also at the rear. That could block the permit-free route.

Can my contractor claim that everything is permit-free?

They may provide an estimate, but the ultimate responsibility lies with you as the client. Always verify the Permit check yourself.

Summary

A dormer on the rear roof surface (and a side roof surface facing the rear yard) is permit-free in many cases, provided it complies with the Bbl conditions and the building is not a monument. The Bouwbesluit, neighbour law and any HOA (VvE) rules continue to apply in full. A Permit check and making inquiries with the municipality remove uncertainty.