When do you need a building permit in Denmark?

A building permit (byggetilladelse) from your municipality is required before you start construction in situations such as:

• Building a new house, summer house, or commercial property.
• Extending or converting existing buildings (adding a floor, balcony, or attic conversion).
• Changing the use of a building (garage → living space, office → shop).
• Removing interior walls in apartments – both bearing (load-bearing) and non-bearing walls require approval, as they affect fire safety, soundproofing, and escape routes.

Small buildings like sheds, carports, and greenhouses may be exempt, but they are still subject to strict rules on size, placement, and plot coverage. Always confirm with your municipality and follow the BR18 building regulations.

How to apply for a permit (step by step)

1. Check local rules: Review your municipality’s lokalplan, plot coverage (bebyggelsesprocent), and BR18 requirements (fire, structure, energy, accessibility).
2. Prepare documents:
   • Site plan & property boundaries
   • Architectural drawings (plans, sections, elevations)
   • Structural documentation for walls, balconies, or load-bearing changes
   • Fire safety and energy calculations where required
   • LCA documentation for new houses and larger projects
3. Apply via Byg & Miljø: Submit digitally through Byg & Miljø using MitID/NemID.
4. Respond to municipal feedback: Authorities may request clarifications or more documents.
5. Receive permit: Once approved, you get a digital permit and can legally start building.

Why permits matter

Securing a permit is more than just a formality:

• It ensures compliance with safety, fire, and energy standards.
• It prevents legal disputes and avoids costly mistakes.
• It protects the value of your property for future sales.

Permit fees & costs

Each municipality sets its own fee structure. Typical costs include:

• Fixed case fees: 1,500–5,000 DKK for simple projects.
• Hourly processing fees: 600–900 DKK/hour for more complex cases.
• External consultancy: Structural engineers, fire safety experts, or energy consultants when required.

Check your local municipality’s gebyr for byggesager for exact rates.

Processing times

Approval times depend on municipality workload and project complexity:

• Small projects (sheds, minor extensions): 2–6 weeks
• Medium projects (balconies, wall removals, conversions): 1–3 months
• Large projects (new houses, commercial builds): 3–12 months

Submitting complete documentation is key to avoiding delays.

Tips to speed up approval

• Submit professional, detailed drawings from the start.
• Hire engineers and architects for structural or fire safety documentation.
• Review the lokalplan early to avoid surprises.
• Respond quickly to municipal questions.

Frequently asked questions

Do I need a permit for a carport or shed?
Often not, if within size limits, but rules on distance to boundary and plot coverage still apply.

Can I begin construction before approval?
No — work must not start until you have the official permit.

How long is a permit valid?
Usually 1–2 years. If work has not started by then, you may need to reapply.

Why choose Permanent Engineers

Getting approval can be stressful and time-consuming. We make it simple by handling the technical documentation and liaising with municipalities on your behalf.

With us, you benefit from:

• ✅ Multidisciplinary expertise – 450+ engineers worldwide covering structure, fire, energy, and more.
• ✅ Local knowledge – we understand how Danish municipalities apply BR18 and local plans.
• ✅ Efficient approvals – correct documentation reduces costly delays.
• ✅ Affordable support – starting from 350 DKK per hour.
• ✅ Peace of mind – we take care of compliance, so you can focus on your project.

👉 Whether it’s removing a wall in your apartment, adding a balcony, or building a new house, Permanent Engineers ensures your permit process runs smoothly and successfully.