Extensions in Costa del Sol detached properties fall into four types: ground-floor annex on free land, upper-floor extension, covered porch or pergola, and terrace enclosure to incorporate it into the usable surface. Each has very different structural, licence and cost requirements, and choosing between them depends on a data point that precedes the project: the real building capacity available under the planning rules for the plot.
Legally an extension is new construction, not an interior renovation. That means three mandatory steps: stamped technical project, major works licence with express grant before starting and, at completion, final works certificate signed by the qualified technician followed by the new-build declaration at the Land Registry. Without those three steps the extended surface is not legally recognised and the property has unregistered square metres, with consequences for inheritance, mortgages and sales.
Our approach starts with a planning feasibility check before commissioning anything to the drafter. Once building capacity and viable type are confirmed, we coordinate the drafting technician with the works execution: site supervision, foundation and structure, watertight envelope, services and finishes. For upper-floor extensions we add a prior structural diagnosis step with inspection pits, because the load-bearing capacity of the existing property is what decides whether a vertical extension is viable or requires prior reinforcement.
