Can two flats be combined, and does the community need to approve
Two flats can be combined if they are adjoining, owned by the same person and the building's statutes do not forbid it. The community's approval is needed when you touch common elements: a load-bearing wall, the facade, risers, the landing. If the wall between the flats is load-bearing, it cannot be opened without the owners' meeting agreeing.
In Catalonia the governing law is Book Five of the Civil Code of Catalonia, not the national horizontal property act. The logic is the same: whatever affects common elements or the building's constitutive title goes to the owners' meeting, and the rest is the owner's decision. Which majority applies in your building is for a lawyer or the property administrator to confirm from the statutes.
The practical order: first check ownership and statutes, then talk to the community, then commission the design. A technical project without the meeting's agreement is wasted money.
How load-bearing walls between flats are opened
An opening in a load-bearing wall is made after the structural engineer's calculation and reinforced with steel beams or a frame. You cannot cut the opening wherever is convenient: your flat and the ones above depend on it.
In old Eixample buildings the walls are often load-bearing brick and the floors rest on steel or timber joists, sometimes with vaults. The engineer surveys the wall, determines the load coming from above and sizes the beam over the opening and the supports at the sides. Temporary props are installed during the work. Once in place the beam is fire-protected and plastered, and the opening is framed so it looks original.
The width of the opening affects the price: a narrow doorway is one solution, a three or four metre passage with a fully open plan is another, with a frame and foundations for the supports. If the wall is only a partition the survey is shorter, but it still has to be done.
Technical issues when combining flats
Besides the wall, services, entrances and safety have to be resolved: two flats mean two water, electricity and gas connections and two front doors, and there should be one home. That means reworking the networks and getting approval.
Electrics are brought into a single board with a fresh power calculation, and the second supply contract is closed. Water and drainage usually stay, but risers are not touched without the community's agreement. Heating and cooling are either built anew or tied together based on the load. The second entrance door is kept as a service door or closed up; either way fire safety and evacuation requirements are taken into account.
The lift lobby and stairs are common elements: if one door opens onto the shared landing, its look and material cannot be changed without consent. New drawings and calculations are also needed for the project the architect will sign. We covered that in our guide on who signs the technical project.
Which documents are needed for registration after combining
After the works, the merger is formalised in a notarial deed and registered; otherwise, legally you still have two separate flats. It is called agrupación.
What is usually needed. A notarial deed of agrupación signed by the owner, describing the new unit and its new share of participation (cuota de participación). The architect's certificate that the new home matches the project and regulations. Land registry extracts for both units and, if there is a mortgage, the bank's consent. Adjustment of the community's title. After registration, an update of the cadastre, which we explain in our guide on the cadastre after building work.
A new energy performance certificate and cédula de habitabilidad for the merged home are also processed, and insurance and meters are updated. Taxes and fees for the transaction should be checked with a gestor or notary because they depend on the case.
Effect on the ITE, certificates and ownership shares
The building's ITE does not change: it is an inspection of the building, not of your flat. But the technician who will open walls benefits from knowing its results, especially if the building has structural remarks.
What does change at flat level: a new energy certificate, a new cédula de habitabilidad and a new share of common costs. Normally the new share is the sum of the two previous ones, and nothing changes for the other owners. But it is in your interest to check how the meeting's resolution is worded: who pays for common works and how the shared bill is split.
If the building has not yet passed its ITE or has outstanding orders, that affects permits and the mood of the meeting. We advise learning the state of the building from documents and the municipal archive first, and designing afterwards. That way there are no surprises after buying the second flat.
Where to start and how BCN YARD runs the project
Start with three documents: land registry extracts for both flats, the community's statutes and the building's plans. With these, the architect and structural engineer can quickly say whether the opening is possible, where and how wide.
Then the order is: measurements and wall survey, agreement with the community, project and licence, works, and finally notary and registry. We handle the technical side: site visit and measurements, a staged estimate, works by our own crew and vetted subcontractors, with one person responsible. The legal side (notary, registry, taxes) is run by your lawyer or gestor; we prepare the works documentation.
Premium renovations start from 3,000 EUR/m2 excluding VAT at the Luxury level, and VAT on renovating second-hand homes in our estimates is usually 21%. The exact price depends on structure and services and is only visible after a visit.
Frequently asked questions
Do I need community permission to combine two flats?
Yes, if common elements are touched: a load-bearing wall, the facade, risers or the landing. If you are only changing internal partitions between your own flats, consent is usually not needed. The required majority is set by the building's statutes and a lawyer should check it.
Which documents are needed to register the combined flat?
A deed of agrupación, land registry extracts for both flats, the architect's certificate on the new unit and the bank's consent if there is a mortgage. After registration the cadastre, energy certificate and cédula de habitabilidad are updated. The notary confirms the new share and the unit's description together with the architect, and the bank's consent is handled separately.
How are load-bearing walls between flats joined?
The opening is cut after the structural engineer's calculation, with temporary props during the work and a steel beam or frame over the opening. The beam is then fire-protected and the opening finished. The width sets the price and the complexity of the supports.
Does the building's ITE change after combining flats?
No, the ITE concerns the building, not the flat. What changes is the energy certificate, the cédula de habitabilidad and the share of common costs, which is normally the sum of the previous shares. It is worth checking the building's condition beforehand.