What it covers

Extending a house means letting it grow without losing what is already good about it. Architect Ana Pinho studies the existing house, the plot and the rules that apply, proposes the best way to gain space and handles the project and the licensing.

The service can include:

a survey of the existing house;
an analysis of what the municipal master plan (PDM) allows you to add;
alternatives to compare: a new floor, a new wing, an annex or better use of existing areas;
the architecture project, submitted to the Câmara Municipal (the municipal council);
coordination with the specialist projects, including structure;
the construction project and the follow-up of the works.

What decides how much you can extend

Each municipality has a master plan (PDM) that sets, among other things, the maximum building area, the height of buildings, the number of storeys and the distances to the plot boundaries. An extension has to fit within those limits together with what already exists.

Then there is the house itself. Adding a floor depends on whether the existing structure can carry it, and the join between the new and the old parts has to resolve roofs, rainwater and insulation. That is why the analysis of the house comes before the drawing.

Depending on the works and the location, an extension may need a licence or a prior notice (comunicação prévia) to the Câmara Municipal. The right procedure is confirmed for each case. If parts of the existing house are not licensed, they may need to be regularised in the same process: see the legalisation page.

How it works

We listen. A conversation about what the house is missing: more bedrooms, a larger living room, a study, room for a growing family. Ana visits the house in person whenever the project calls for it.
We counsel. A survey of the house and a study of the alternatives possible within the PDM, with the advantages and costs of each.
We solve. The architecture project, submitted to the Câmara Municipal with the specialist projects it needs. Ana follows the process until the decision.
We deliver. The construction project and the follow-up of the works, so the new part and the old one work as a single house.

What to gather

The tax record (caderneta predial) and the land registry certificate (certidão permanente).
Approved plans and earlier licences, if they exist.
A topographic survey, when the extension takes up new ground.
Photographs of the house and a list of what you need.

Timelines and fees

Timelines depend on the project: the size of the extension, the condition of the existing house and how long the Câmara Municipal takes to appraise it. After the first visit, Ana gives you a realistic estimate.

Fees are set for each project in a clear proposal and paid in stages as the work progresses.

Frequently asked questions

Can I stay in the house during the works?

It depends on the scale of the works. A side extension or an annex usually lets the family stay at home; adding a floor, or works that touch the structure, may need a temporary move. This is discussed during the study, with time to plan.

Do I need a structural engineer?

Yes, whenever the extension touches the structure or adds a floor. The structural project is one of the specialist projects and is prepared by a qualified engineer.

What if the PDM does not allow an extension?

Sometimes you can gain space by reorganising the interior of the house, without adding building area. The initial analysis shows the alternatives before any decision.

Can I extend and renovate at the same time?

Yes, and it often pays off. When the works are already touching the house, it is the right moment to improve the insulation, the services and the layout of the existing rooms. The project treats the house as a whole, not just the new part.

How much does an extension cost?

The cost of the works depends on the area being added, the materials and how much of the existing house needs to change. The project fees are set in a proposal for your case. During the study, Ana helps you see which solutions fit your budget.

Find out more

Meet architect Ana Pinho and see how a project works, or look at the renovation and interior design services.

Extending a house in Portugal