Portugal's RGEU in 2026: minimum sizes by home type, minimum ceiling height and the rules that decide a legalization

The RGEU is the 1951 technical regulation that sets the safety, health and appearance requirements for buildings. For anyone who owns or wants to create a home, the key part is the chapter on interior layout (articles 65 to 82): ceiling height, number and size of rooms, minimum gross floor area of each dwelling, windows, ventilation, basements and attics. It has been amended many times; the latest amendment, the 17th, was made by Decree-Law 108/2026.

The Simplex reform (Decree-Law 10/2024, Portugal's 2024 planning simplification law) ordered the RGEU repealed as of June 1, 2026, while the professional bodies prepared technical rules as part of the Código da Construção (article 25). Decree-Law 108/2026 rewrote that article: the RGEU is only repealed when the law setting the technical rules for buildings takes effect, prepared with input from the professional bodies. This change took effect on June 1, 2026, the first business day after publication (article 13(2)), so the repeal never took effect.

That law does not exist yet. Order (Despacho) 12528/2026, published on October 15, 2026, set up a working group to draft a proposed Código da Construção, with representatives of the Secretary of State for Housing, IMPIC (the construction and real estate regulator), LNEC (the national civil engineering laboratory) and Construção Pública, without setting a deadline. Many websites still say the RGEU was repealed in June 2026; it was not. A design, legalization or change of use filed today must comply with the RGEU.

Read the consolidated text in the Diário da República (Portugal's official gazette), with one caution: in articles 66 and 67 the size table appears as «ver documento original» (see original document), and the sizes in force are those of Decree-Law 650/75 of November 18, which rewrote the articles on ceiling height, sizes, dimensions and windows. Decree-Law 95/2019 restored that law with effect from the date it had been repealed (article 19).

The table sums up the changes that matter if you own a home, want to legalize work or want to change how a space is used.

Article 66 sets the number and minimum size of the rooms in each home, and article 67 the minimum gross floor area of the dwelling. The T type is the number of bedrooms: a T1 has one bedroom and a T0 is a studio (article 66(5)). Entrance halls, bathrooms and storage rooms do not count as rooms. The mandatory extra area cannot be a separate enclosed space: it is spread across the kitchen and living room and includes a laundry area, of at least 2 m² when it is a separate space (article 66(2) to (4)).

Above T6, the main bedroom stays at 10.5 m², other double bedrooms at 9 m² and single bedrooms at 6.5 m², the living room at 16 m² and the kitchen at 6 m²; the extra area becomes (x + 4) m², where x is the number of bedrooms, and the gross floor area becomes 1.6 times the habitable area. Since 2024, a kitchenette or open kitchen can merge with the living room, as long as the combined area is not less than the sum of the minimum areas for that home type (article 66(6) and (7)).

Besides floor area, each room must have a usable shape (article 69), bathrooms have their own minimums (article 68), and it helps to know which area is being measured (article 67(2)):

• Rooms under 9.5 m²: the minimum dimension is 2.10 m. Between 9.5 and 12 m², a circle 2.40 m across must fit inside; between 12 and 15 m², a circle of 2.70 m. From 15 m², the length cannot exceed twice the width, unless there are windows on the two opposite walls furthest apart.
• Kitchen: minimum dimension of 1.70 m and at least 1.10 m clear between counters on opposite walls (article 69(3)).
• Bathrooms: 3.5 m² in T0, T1 and T2 homes; 4.5 m² in T3 and T4 homes, split into two spaces with separate access; 6 m² in T5 homes or homes with more than six rooms, also in two spaces. The minimum fixtures are a bathtub or shower, a toilet and a washbasin; bidets stopped being mandatory in 2024.
• Gross floor area (área bruta): the total area of the home measured to the outside of the exterior walls and to the centerline of walls shared with other homes, including private balconies, ancillary spaces and the home's share of common hallways.
• Usable and habitable area: usable area adds up all rooms measured inside, including halls, hallways, bathrooms and storage; habitable area adds up only living rooms and bedrooms, without those spaces.

In a home, the minimum floor-to-floor height is 2.70 m and the minimum clear ceiling height (pé-direito), measured between the finished floor and the finished ceiling, is 2.40 m (article 65(1)). The article only allows lower figures in certain spaces and situations:

• 2.20 m in entrance halls, hallways, bathrooms, pantries and storage rooms (article 65(2)).
• 3 m on floors used as retail stores (article 65(3)).
• Sloped, beamed or vaulted ceilings: the minimum must be met over at least 80% of the ceiling area; elsewhere, a home's ceiling can drop to 2.20 m (article 65(4)).
• Attics, garrets and mansards: they can only be used as living space if they meet the requirements for residential floors. The regulation ceiling height may cover only half the room's area, but at any point more than 30 cm from the room's perimeter the height cannot be less than 2 m, and thermal insulation must be provided (article 79).
• Basements: they can only be living space in exceptional cases, with one exterior wall fully exposed from 0.15 m below floor level and the habitable rooms along that wall (article 77). A storage basement needs a 2.20 m ceiling and cannot connect directly to the residential part of the building (article 78).

A room without a proper window does not count as a bedroom or living room under the RGEU. When legalizing enclosed balconies (marquises) and annexes, these are the rules that most often decide the case:

• Windows (article 71(1)): each bedroom, living room or kitchen gets light and air through openings directly to the outside, with a total area of at least one tenth of the room's floor area and never less than 1.08 m², measured on the rough opening. Narrow slits in walls facing neighboring land or buildings do not count.
• Enclosed balconies (article 71(2)): where climate and noise justify it, they count as outdoor space if they are no more than 1.80 m deep, if the openings of the rooms behind them are at least one fifth of the room's area and 3 m², if the glazing is at least one third of the balcony's area and 4.3 m², and if half of the glazing opens for ventilation.
• Cross ventilation (article 72): each home must be ventilated from side to side, normally through windows on two opposite facades.
• Clearance in front of a window (article 73): the wall or facade opposite must be at least half its height above the room's floor away, with a minimum of 3 m, and there can be no obstruction within 2 m on either side of the window's centerline.
• Distance between facades (article 60): between facades with windows from living spaces, the minimum is 10 m; on streets already lined with buildings, the council can accept less, but not less than the existing buildings set.

Turning an annex, garage or attic into living space is a change of use and, almost always, building work. With no work, or only exempt work, it is done through a prior notice with a waiting period, with a statement of responsibility certifying that the building is fit for that use (articles 4(5), 62-B and 63 of the RJUE, Portugal's planning and building code); with work that needs a permit, through a license or prior notice. Either way, the architect or engineer can only sign if the space complies with the RGEU, and the process is explained in the guide on the habitation license.

The PDM (Plano Diretor Municipal, the municipal master plan) comes before the RGEU: it must allow residential use and, if the annex is a separate house, one more dwelling on the plot. Once past that filter, these are the practical tests:

• Annex as a separate house: it needs at least the gross floor area of a T0 (35 m²), with a 10 m² living room, a 6 m² kitchen, 6 m² of extra area and a 3.5 m² bathroom.
• Annex or garage as a bedroom of the main house: the bedroom must have the size required for the resulting home type, for example 10.5 m² for the main bedroom, and the shape required by article 69.
• Ceiling height: below 2.40 m, the space cannot be a bedroom or living room, but it can be storage or a bathroom with 2.20 m.
• Window: the room needs openings to the outside of one tenth of its area and at least 1.08 m², and the window must meet the clearance in article 73.
• Attic: the article 79 rule applies, with the regulation height over half the area and never less than 2 m more than 30 cm from the walls.
• Basement or below-grade garage: it is only habitable in the exceptional cases of article 77.

Work done without a permit can only be legalized if it can be brought into line with the rules in force (RJUE article 102-A(1)). Paragraph 5 allows the council to waive technical rules that have become impossible or unreasonable to meet, as long as the work met the technical requirements in force when it was done, and the applicant must prove that date. Since the 2.40 m ceiling height and the minimum sizes have applied since 1975, an annex built later with a 2.20 m ceiling cannot get a waiver on that point. On request, the council must explain within 15 days how the legalization should proceed (paragraph 6); the procedure is covered in the guide on legalizing building work.

For anything built lawfully, existing-building protection applies: buildings put up under earlier rules are not affected by later rules, and alteration or rebuilding work cannot be refused on the basis of those later rules if it does not create or worsen nonconformities, or if it improves safety and health conditions (RJUE article 60). For homes older than the RGEU, see the guide on legalizing an old house and annexes.

There is also a separate regime for renovating residential buildings whose construction permit was issued by January 1, 1977 (Decree-Law 95/2019). Ordinance (Portaria) 304/2019 sets alternative requirements to the RGEU, which still applies in the background; in extensions, the new part follows the RGEU. The table compares the main figures.

These mistakes sink many legalization and change-of-use applications:

Measuring, checking against the RGEU and choosing the right route is work for an architect with access to the municipal file. Apto Group reviews the space and the file and tells you whether legalization or a change of use is feasible, through our building legalization and change of use services.

• Assuming the RGEU was repealed and designing to lower figures.
• Using the areas on the caderneta predial (the property tax record), which follow tax criteria, to check RGEU sizes.
• Measuring ceiling height before the flooring, insulation and dropped ceiling go in: what counts is the clear height once everything is finished.
• Counting an enclosed balcony as outdoor space without meeting the conditions of article 71(2).
• Expecting the article 102-A waiver to fix work that did not meet the rules of its own time.
• Meeting the RGEU without first checking that the PDM allows the use and the number of homes you want.

The official sources are in Portuguese. Check the version in force before preparing a notice, project or application.

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