Change of Use: Technical Rigor and Commitment to Permanent Housing

The recent ruling by the Spanish Supreme Court —no. 700/2026, dated June 4th— establishes that projects transforming commercial premises into housing must be signed by an architect. This is a sound decision: a change of use is not a minor renovation, but a major intervention that alters the building’s function and requires strict verification of habitability, safety, accessibility, ventilation, and functionality.

Transitioning from a space designed for commercial activity to a home involves meeting technical requirements that affect both the future inhabitants and the building as a whole. Therefore, it is reasonable that the architect assumes the responsibility for the project, in accordance with the Law on Building Ordinance (LOE). Their training allows them to approach the change of use from a holistic perspective: urban regulations, architectural configuration, structural integrity, fire protection, and residential quality.

This ruling does not mean that other professionals cannot participate. On the contrary, technical architects (surveyors), engineers, and contractors play a vital role in directing and executing the works. However, the project that officially turns a shop into a home must have a global technical responsibility, especially when the right to live in dignified and safe conditions is at stake.

An Opportunity That Must Serve a Social Purpose

That said, professional jurisdiction should not be the only element of the debate. Converting commercial units into housing can help expand the residential stock, but only if they are oriented toward their true purpose: creating stable homes.

Therefore, administrations should ensure that authorizations, administrative simplifications, or incentives associated with these changes of use are granted solely and exclusively when the resulting property is dedicated to a primary residence or traditional long-term rental.

This condition would ensure that urban, technical, and administrative efforts have a real impact on housing access. If these new properties end up in the holiday rental market or short-term stays, the change of use fails to effectively increase the supply available to local residents. It might generate economic activity, but it does not solve the problem for people searching for a place to live.

Real Homes for City Residents

Linking changes of use to primary residency and traditional rentals would help:

• Increase the effective residential supply, incorporating homes for individuals and families who need stable housing.

• Ease price pressure in areas where there is a shortage of long-term available housing.

• Prevent speculative use, ensuring that a measure designed to expand the residential stock does not become a shortcut for multiplying temporary accommodations.

• Protect neighborhood life, fostering communities with permanent residents and sustained urban activity throughout the year.

• Guarantee quality and safety, by requiring projects drafted by architects that certify compliance with all technical requirements.

Transforming empty or underutilized commercial spaces can be part of the answer to the housing shortage in Spain, provided it is done with criteria of quality, safety, and responsibility. The architect must be the professional leading these projects technically; but, at the same time, their approval should be linked to a clear and verifiable residential purpose.

Converting commercial units into housing is useful. Converting them into stable homes for permanent residency is what will truly help mitigate the housing crisis.