What does a ridge-raising permit cost?
For a ridge raising there are three cost items: drafting (architect or drawing bureau) indicatively €300–€1,200, structural calculation €600–€1,000, and municipal fees (variable, depending on construction sum). A ridge raising is almost never permit-free because the roofline changes.
Drafting
An architect or drafting bureau produces the building drawings, cross-sections and elevations the municipality requires. Indicatively €300–€1,200, depending on complexity (existing drawings available or not, level of detail) and region. Ask for a clear scoped quote in advance.
Structural calculation
A ridge raising substantially changes the roof structure: the trusses are extended or replaced and the joists/couplings must match. A structural engineer produces the calculation the municipality requires with the application. Indicatively €600–€1,000, sometimes higher for an unusual roof structure or if soil testing is required.
Municipal fees
Municipal fees for a building-activity omgevingsvergunning are usually a percentage of the construction sum (often 2–4%). For a ridge raising of €25,000–€40,000 that means roughly €500–€1,500 in fees. The exact rate is in your municipality's fee schedule.
Why (almost) never permit-free
A ridge raising changes the height and silhouette of the roof — placing it outside the permit-free categories of the Bbl. In almost all cases count on a full application procedure with an aesthetics review.