This is the municipal permit that authorizes renovation or construction work. In Spain, it is mandatory when there are structural alterations, changes to the façade, or changes in use; for minor interior work, prior notification or a responsible declaration is usually sufficient. Understanding when to apply for a building permit avoids penalties, stoppages, and costly delays.
Definition:
A planning permission that verifies that your project complies with regulations (planning, safety, accessibility, and efficiency). Without a valid building permit, the city council can halt work, impose penalties, and demand subsequent legalization. In comprehensive renovations, it usually coexists with other permits (occupation of public roads, waste management, heritage protection).
What procedure do you need?
Not all renovations require the same procedure. The rule of thumb: greater impact, greater requirements. When the scope is limited and you are not touching protected or common elements, a notification may suffice; if you alter the structure, envelope, or use, you need a building permit.
| Performance | Standard procedure | Comments |
|---|---|---|
| Knocking down or opening holes in load-bearing walls, slabs, beams | Building permit (major) | Requires technical project and project management (LOE). |
| Modify facade or roof: new windows, terrace enclosure, skylights | Building permit | In protected buildings, heritage report. |
| Extensions: habitable lofts, annexes, increase in buildable area | Building permit | Adjustment to planning and structural calculations. |
| Change of use (e.g., commercial to residential) | Building permit | Full compliance with the Technical Building Code (CTE) and habitability. |
| Interior renovations without structural work (non-load-bearing partitions, finishes) | Prior notification / responsible declaration | Provide a report, simple plans, and a budget. |
| Renovation of private facilities (electricity, plumbing, air conditioning) without affecting common elements | Prior notification | If you modify general connections, you may need to obtain a license. |
| Install outdoor air conditioning unit on facade or roof | Building permit | Also authorization from the homeowners' association. |
Useful sources: BOE – Law 38/1999, LOE, Technical Building Code, and Madrid City Council licensing guide.
Signs you need
You are going to intervene in the structure or open holes in the facade.
You want to enclose a terrace, change the exterior appearance, or create a new entrance.
You increase the usable or built area.
You change the use of the property.
Affects common elements (courtyards, shunts, slabs, general downspouts).
Documentation and standard fees
Major work (building permit)
Approved technical project (architect/technical architect), health and safety study, project management, waste management, urban planning fees, and waste deposit. The building permit may also require authorization from the community and, if applicable, a heritage report.
Minor works (communication)
Descriptive report, sketches or basic plans, measurements, budget, and reduced rates. Even if it is "minor," keep receipts and photographs: they will help you in the event of inspections.
Deadlines: how they fit into your schedule
Processing times vary depending on the municipality. For a major building permit, allow several weeks or months; prior notification usually allows work to begin almost immediately if the documentation is complete. Include the "critical path" of the building permit in the schedule for purchasing materials and hiring tradespeople to avoid delays.
Frequent casuistry
Interior
Redistribution of non-load-bearing partitions, replacement of flooring and tiling, replacement of bathroom fixtures and kitchen furniture are usually subject to notification. If you move general downspouts or alter the structure, you will need a building permit.
Facade and roof
Replacing windows while maintaining dimensions and color may vary by city: some city councils require a building permit; others accept a declaration of responsibility. Enclosing terraces, creating new openings, or changing tiles/waterproofing with aesthetic alterations require a building permit.
Facilities
Outdoor air conditioning units, chimneys, smoke vents, or equipment on the roof usually require a building permit and community agreement. Changes in power or connections may require specific projects.
Communities and common elements
Even if you obtain your building permit, work on common elements requires permission from the homeowners' association. Agree on access, schedules, protection of common areas, and use of the elevator. Keep approval records: they are as important as the building permit itself.
Penalties, inspections, and retroactive legalization
Working without a building permit when one is required involves risks: stop orders, fines, the obligation to restore the original state or to legalize with additional costs and delays. In protected buildings, the penalties are higher. If you have already completed part of the work, consult a technician to discuss legalization with an "as built" project.
Tips for speeding up processing
Submit complete and consistent documentation: plans, reports, and aligned measurements.
Review municipal ordinances before defining solutions (alignments, occupancy, aesthetics).
Request a technical appointment with the Urban Planning Department to validate criteria before registering.
If you anticipate occupying public roads (scaffolding, containers), apply for this at the same time as the building permit.
Use digital signatures and visas to avoid back-and-forth communication.
Author
Cabana Team
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