Portugal has the clearest national thinking in Europe on what makes a house a building rather than a vehicle. It is also mid-reform: the whole permit system changes on 1 October 2026.
Do you need a permit? The RJUE (Decreto-Lei 555/99) governs, and it is being rewritten. Decreto-Lei 108/2026 takes effect on 1 October 2026, having been postponed from August by Decreto-Lei 155-B/2026. A correction notice in July also restored Article 62 and revoked Article 62-C, so any commentary written from the May text is working from a defective version.<br><br>What matters for you. From 1 October there are three forms of prior control: licença, comunicação prévia and the new comunicação prévia com prazo. A new standalone house gets the lighter comunicação prévia route only where the plot is already covered by a plano de pormenor, a unidade de execução or a loteamento that fixes the alignments and building footprint, or sits in consolidated urban fabric. On an unplanned plot, and almost always on solo rústico, you stay on the licença track. The reform is real, but it does not open a fast lane for a house on a bare plot.<br><br>There is still no size threshold that exempts a dwelling. The obras de escassa relevância urbanística exemption in Art. 6-A covers small ancillary structures beside an existing house, not a standalone home.<br><br>And wheels still do not decide it. The national guidance Recomendação CNT 1/2019 is untouched by the reform: the outcome should not turn on "a existência de rodas", and connection to mains water, sewage, electricity or gas is the decisive sign of permanence. A genuinely mobile, unconnected, temporarily parked house can be a vehicle. The same house levelled on supports and plumbed in is an edificação.
Which energy standard applies. Decreto-Lei 101-D/2020 governs energy certification. Single-family dwellings under 50 m² are exempt from the certificate, but not from the envelope requirements. Maximum U-values from Portaria 138-I/2021 by winter climate zone, W/(m²·°C): opaque walls 0.50 (I1) / 0.40 (I2) / 0.35 (I3); roof and floor 0.40 / 0.35 / 0.30; glazing Uw 2.80 / 2.40 / 2.20. Our standard mobile build (wall U 0.44, roof U 0.42) meets zone I1 for walls but not the roof; our semi-mobile and non-mobile builds meet all three zones.
Getting the house to you. Standard limit 2.55 m wide, 4.0 m high (Portaria 472/2007). Above that an AET from IMT is required, with a copy to Infraestruturas de Portugal before the trip. Above 3.0 m wide, one pilot car. A 4 m-high house body on a trailer deck will exceed 4.0 m total, so plan for an AET.
What you pay in VAT. Standard rate 23%. A temporary 6% rate for housing construction exists from 1 July 2026 under Decreto-Lei 97/2026, but whether it reaches a factory-built house is unresolved – assume 23% and take Portuguese tax advice before relying on the reduced rate. Delivery with installation makes place of supply Portugal and requires Portuguese VAT registration.
Can you register it as your address? From 1 October the licença de utilização is replaced. Where the works went through prior control you file a comunicação prévia de utilização under Art. 62-A, and use may begin on submission. Where they did not, Art. 62-B's comunicação prévia com prazo applies instead. Either way the house has to have been licensed to become a morada fiscal; unlicensed, it is an illegal work exposed to a demolition order.
The catch. Two things. The reform lands on 1 October 2026, so anything you were told before that date should be re-checked, and the municipal instruction lists are still being republished. And Art. 6-A lets each of the 308 câmaras municipais add its own exempt categories by municipal regulation, so there is genuinely no national answer to "does mine need a permit". Ask your câmara.
If you're at the point of talking to your building office, tell us and we'll put together the drawings, weights, U-values and technical file you'll need to take with you. It's free, and it's the part we're best at.
Where this comes from
Decreto-Lei 108/2026 de 29 de maio, 21.ª alteração ao RJUE openDecreto-Lei 155-B/2026 de 31 de julho, entrada em vigor a 1 de outubro de 2026 openDeclaração de Retificação 29-A/2026/1 de 27 de julho openRecomendação CNT 1/2019, estruturas amóveis e casas amóveis, DGT openCM Lisboa, utilização após operação urbanística sujeita a controlo prévio (Art. 62.º-A) openPortaria 138-I/2021, Anexo I, coeficientes de transmissão térmica máximos openPortaria 472/2007, Regulamento de Autorizações Especiais de Trânsito open