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DL 97/2017 · Artigo 17.º·Updated August 2026

Condominium gas inspection

Condominium gas inspection is mandatory. The gas riser is a common part of the building, so the duty sits with the condominium rather than with each owner. In residential buildings the cycle is five years. InspectOS coordinates the building inspection with a DGEG-accredited Entidade Inspetora de Gás (EIG) and quotes per building.

5 years · residential (UT I)Condominium paysQuoted per building

Who is responsible: the condominium or the owner?

The general rule in Decreto-Lei n.º 97/2017 is that the owner or usufructuary must arrange the inspection and bear the cost. Artigo 17.º then sets out an explicit exception for buildings held in propriedade horizontal.

DL 97/2017, Artigo 17.º, n.º 2, alínea a)

Inspections of the common parts of a building held in propriedade horizontal are the responsibility of the condominium.

DL 97/2017 does not divide the installation. Artigo 2.º, alínea l) defines the gas installation as a single system running from the building's main shut-off valve to the appliance shut-off valves. What separates common from private is the propriedade horizontal regime: Artigo 1421.º, n.º 1, alínea d) of the Código Civil makes a building's general gas installations common by law. In practice the boundary is drawn at each unit's meter: upstream is common, downstream belongs to the unit and the duty is the owner's, unless the tenancy agreement transfers it to the tenant.

ElementWhere it starts and endsWho inspects and pays
Main shut-off valve and riserFrom the building entry to each unit's meterCondominium
Floor and unit branchesFrom the riser to the meterCondominium
Unit installationFrom the meter to the gas appliancesOwner, or tenant if the agreement says so
Central building boilerCollective installation in a common partCondominium

How often is condominium gas inspection mandatory?

The interval in Artigo 21.º depends on the building's utilização-tipo, classified under Decreto-Lei n.º 220/2008, and not on whether the installation is common or private. A residential building is utilização-tipo I, which is absent from the three-year list. A residential building's riser therefore follows the five-year cycle.

Building typeIntervalLegal basis
Residential (UT I), including the riser and common parts5 years, for installations over 10 years old and not remodelledArtigo 21.º, n.º 1
Retail, hotels, restaurants, education, healthcare, sport, industry (UT III to XII)3 years, regardless of ageArtigo 21.º, n.º 1, a)
Buildings outside the listed utilisation types that receive the public3 yearsArtigo 21.º, n.º 1, a)

A building with a commercial unit at street level can carry both regimes at once. The installation serving that business follows the three-year cycle while the riser serving the flats follows the five-year one. Confirm the utilização-tipo before scheduling.

What happens if the mandatory inspection is not carried out: under Artigo 21.º, n.os 2 and 3, DGEG notifies the responsible party to complete it within three months, and once that window closes the distributor cuts off the building's gas supply. In a block the cut reaches every unit served by the riser, not only the owner at fault. Supply is restored only after a fresh inspection passes.

What is inspected in the common parts

The common-parts inspection covers the principal elements of the collective installation defined in DL 97/2017:

  • Building main shut-off valve, including access and signage
  • Pressure reducer and limiter, where fitted
  • The full length of the riser
  • Floor and unit branches up to each meter
  • Ventilation of the spaces where gas appliances are installed or intended to be installed
  • Central boiler and its combustion-product flue, where one exists

Once the inspection is complete the EIG issues a declaração de inspeção stating whether the installation passed or failed (Artigo 16.º). That is the statutory document, commonly called the boletim or the building's certificado de gás. The administrator should file it and make it available to owners, because it is what evidences the building's compliance to DGEG, insurers and buyers.

What it costs and how it is quoted

An individual apartment inspection starts at from €110. Common parts are not quoted from that table, because the work depends on the number of floors, the number of units served by the riser, whether there is a central boiler, and access to the plant rooms.

The building inspection is therefore quoted per building, after a survey. Where the condominium schedules the riser and several owners have their own units inspected on the same visit, the team's repeat travel is avoided. Each inspection keeps its own Boletim and its own price.

How to proceed

  1. Gather the building details: number of floors and units, year the gas installation was built, date of the last inspection, and whether there is a central boiler.
  2. Request a quote from InspectOS with those details. We reply with a figure for the building and an available date.
  3. The cost falls to the condominium under Artigo 17.º. How it is approved depends on the building's título constitutivo and rules, so confirm with the administrator whether it proceeds as an act of conservation or needs a vote at the owners' meeting.
  4. The inspection is carried out by a DGEG-accredited EIG we work with, whose credentials we verify before each assignment.
  5. Receive the declaração de inspeção and file it. It sets the date of the building's next inspection.

Related services

Official sources

Sources: Decreto-Lei n.º 97/2017, of 10 August, as amended by Lei n.º 59/2018, of 21 August (Artigos 2.º, 4.º, 16.º, 17.º and 21.º); Código Civil, artigo 1421.º, n.º 1, alínea d); Decreto-Lei n.º 220/2008, of 12 November, artigo 8.º (utilisation types); Direção-Geral de Energia e Geologia.

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