# Earthquakes and roofs in Portugal: chimneys, tiles, what to do and the law on works

> What happens to the roof in an earthquake, the most fragile old buildings, what to do before, during and after according to Civil Protection, when works need a seismic report and what we could not confirm.

- Page: https://telhadoseguro.pt/en/guides/earthquake-roof-home-safety
- Language: English
- Updated: 2026-11-04

## Summary

- Nobody predicts earthquakes (IPMA). Chimneys, parapets and loose tiles sit at the top and fall easily; most injuries come from things that fall.
- During the shaking: drop, cover, hold on (ANEPC). Afterwards: do not climb onto the roof, turn off water and gas, leave if there is serious damage and call 112 in an emergency.
- A lighter roof alone does not make a building safe. The connections, the walls and the timber also matter: only an engineer can assess your building.
- Alteration, extension or reconstruction works may need a seismic vulnerability report and a strengthening design (Portaria n.º 302/2019). We found no national aid for strengthening.

In an earthquake, tiles, chimneys and parapets are among the first things to fall. This guide explains what happens to the roof, what to do beforehand and straight afterwards, and what the law asks for when you carry out works.

*Updated on 4 November 2026. General information. It is not a structural assessment and does not guarantee the safety of any building: only a civil engineer can assess that, building by building.*

## The essentials

- **Nobody predicts earthquakes.** The IPMA says short-term prediction does not yet exist. Prepare beforehand.
- **The top of the house is the weak point.** The IPMA mentions falling chimneys, balconies and ceilings, and says most injuries come from things that fall.
- **During: drop, cover, hold on** ("baixar, proteger, aguardar"). These are the three gestures of Civil Protection (ANEPC).
- **Afterwards: do not climb onto the roof.** Leave if the house has serious damage and only go back when the authorities advise it. Emergencies: 112.
- **Some roof works require a seismic report** (Portaria n.º 302/2019).

## The risk in Portugal

The IPMA describes mainland Portugal as an area of intermediate seismicity. The brochure by the ANEPC and the Portuguese Insurers' Association (2018) says Lisbon and the Algarve are among the regions most prone to earthquakes.

Structures are designed with Eurocode 8 (NP EN 1998-1:2010) and its National Annex. According to the LNEC study that prepared the annex, there are two scenarios: **type 1**, earthquakes with their epicentre mainly at sea, and **type 2**, mainly on land. Each municipality (concelho) was placed in a zone. The zone of your municipality is given by the engineer on the project.

## What happens to a roof in an earthquake

A thesis from the Faculty of Engineering of Porto (FEUP, 2020) studied chimneys, parapets and railings at the top of old stone houses and says they can be very vulnerable. It lists what decides whether an old façade falls outwards: the connections between walls, the connections of the walls to the floors and to the roof, tie rods or ring beams, and the quality of the masonry. It notes that the roof can push the walls and that its weight generates forces during an earthquake.

The table brings together the sources and our own practical suggestions:

| Element | Why it is a concern | What to do |
|---|---|---|
| Chimney | Tall and narrow. The IPMA mentions chimneys collapsing and fires starting in them | Assessment by an engineer; the flashing is covered in the guide on [chimneys and flashing](https://telhadoseguro.pt/en/guides/chimney-flashing-roof-joins) |
| Parapet | Wall at the top of the façade, can fall onto the street | Assessment by an engineer |
| Loose tiles | Can fall with the shaking | Replace them as normal maintenance |
| Roof-to-wall connection | If weak, they do not work together | Only an engineer designs the strengthening |
| Heavy roof on weak walls | More mass at the top | Do not change it without a structural assessment |

**Old buildings.** The LNEC says **"gaioleiro"** buildings (from the mid-19th to the early 20th century) have high seismic vulnerability because of weak materials and poor building techniques. In its tests, strengthening the connections between walls and floors and fitting tie rods between opposite walls mainly helped to control walls collapsing outwards. **Pombaline** buildings were designed after 1755 to resist better, but a study by the IST and the LNEC says most now need strengthening, partly because of past works that harmed their seismic resistance.

**A lighter roof is not enough.** In our reading of the sources, weight is only one factor: the connections, the walls and the timber also matter. A lighter roof alone does not make a building safe, and changing the weight can change how the structure behaves. Before a [sandwich panel](https://telhadoseguro.pt/en/guides/sandwich-panel-roof) roof, talk to an engineer.

## Before: what you can do

- **Look from the ground**, with binoculars: tiles out of place, a leaning or cracked chimney. Do not climb up (see [work at height](https://telhadoseguro.pt/en/guides/work-at-height-roof)).
- **Ask a civil engineer for an assessment** if the house is old, of masonry, has a tall chimney or a parapet over the street, or if past works removed walls.
- **Follow the ANEPC:** fix bookcases and heavy furniture to the walls, put heavy objects low down, prepare an emergency kit and teach everyone how to turn off the water, gas and electricity.
- **Check your insurance.** The ANEPC asks you to confirm whether the policy covers earthquakes; in 2018 the brochure estimated that only 15% of homes had that cover. In April 2026 the Government announced mandatory insurance for homes, but we did not find the law published. See the guide on [home insurance](https://telhadoseguro.pt/en/guides/home-insurance-storm-roof).

## During the earthquake

Drop down, protect your head and neck and wait until the ground stops shaking. Indoors, shelter by a beam or pillar, in a corner or under a sturdy table, away from windows. Do not rush to the stairs or use the lift. In the street, keep away from run-down buildings, walls, chimneys and balconies (ANEPC).

## After the earthquake

From the ANEPC: expect **aftershocks** and, near the sea, a possible **tsunami** (go to high, open ground). **Turn off the water and gas and switch off the electricity**, and do not strike matches. **Leave the house** if there is serious damage or a risk of collapse. For serious injuries, gas leaks or fires, **call 112**.

What we add, as common sense and not as an official rule:

1. **Do not go onto the roof or into the loft** if you see new cracks or hear creaking. Aftershocks loosen what stayed in place.
2. **Look from a distance:** a twisted chimney, a ridge out of place, a cracked gable, tiles on the ground.
3. **Indoors**, look for new cracks in walls and ceilings, especially diagonal ones or near corners, and doors that no longer close. Photograph everything (see the [first 48 hours](https://telhadoseguro.pt/en/guides/damaged-roof-first-48-hours)).
4. **Call a civil engineer** if you see these signs. If there is a danger to the street or to neighbours, tell the town hall (Câmara): the RJUE lets it order safety works or the demolition of anything threatening to collapse, at the request of any interested party (article 89), and waive formalities when there is an imminent risk of collapse (article 90(8)).

## The law when you work on the roof

Repairing the roof as it was is conservation work (see the [roof works permit](https://telhadoseguro.pt/en/guides/roof-works-permit-2026)). Seismic rules come in for **alteration, extension or reconstruction** works, whatever the age of the building (Decreto-Lei n.º 95/2019).

**Portaria n.º 302/2019**, in force since 15 November 2019, requires a seismic vulnerability assessment report when there is:

- clear evidence of deterioration of the structure;
- a change in the structural behaviour of the building;
- an area of works above 25% of the gross floor area;
- a cost above 25% of that of an equivalent new building.

In schools, hospitals and other buildings of importance class III or IV, the limits drop to 15%. If the building does not meet 90% of the seismic action of NP EN 1998-3:2017, a **seismic strengthening design** is mandatory. According to the Câmara of Amarante, the report is prepared by a qualified civil engineering professional.

The decree-law revoked, for buildings, the Safety and Actions Regulation (RSA, of 1983) and the 1958 earthquake regulation. Despacho Normativo n.º 21/2019 brought the Eurocodes into structural design for buildings, with a three-year transition.

In our reading, replacing a heavy roof with a light one, or timber with concrete, may "change the structural behaviour". Ask the engineer and the town hall, in writing, before signing a contract.

## Aid

We found no national aid for seismic strengthening of private homes; the fund announced in 2026 is about insurance. In Lisbon, according to Lusa (June 2025), the ReSist programme was due to launch **technical support** for private buildings in 2026, which we did not confirm.

## What we could not confirm

- **The seismic zone of each municipality:** we read the LNEC study (2008), not the standard, which is sold by the IPQ.
- **The numbering of the seismic article** of Decreto-Lei n.º 95/2019: the portaria refers to article 7, the consolidated version we read shows article 8. The Diário da República website did not respond on 4 November 2026.
- **Changes in 2026** to the decree-law and the portaria after the RJUE revision.
- **Whether replacing the roof counts as a structural change:** we read no official interpretation.
- **ReSist's technical support and the mandatory insurance law.**
- **An official guide to securing chimneys and parapets.** We also did not read the "Aprender a prevenir" campaign or the National Emergency Plan.

## Sources (read on 4 November 2026)

- ANEPC and Associação Portuguesa de Seguradores, [Sismos: prepare-se e proteja-se](https://prociv.gov.pt/media/ovjbpe1c/sismos-prepare-se-e-proteja-se.pdf), November 2018.
- ANEPC, [A Terra Treme](https://www.aterratreme.pt) (the three gestures).
- IPMA, [What to do in an earthquake](https://www.ipma.pt/pt/enciclopedia/geofisica/caso.sismo/index.html) and [Seismology FAQ](https://www.ipma.pt/pt/educativa/faq/geofisica/sismologia/index.html).
- A. Campos Costa, M. L. Sousa and A. Carvalho (LNEC), [Seismic zonation for Portuguese National Annex of Eurocode 8](https://iitk.ac.in/nicee/wcee/article/14_07-0167.PDF), 2008.
- P. Candeias and others (LNEC), [Avaliação da vulnerabilidade sísmica de edifícios de alvenaria](https://repositorio.lnec.pt/bitstream/123456789/1008622/2/T2_CANDEIAS_r125.pdf) (no visible date).
- A. Gonçalves and others (IST and LNEC), [Comportamento dinâmico de paredes de frontal pombalinas reforçadas](https://repositorio.lnec.pt/bitstream/123456789/1008611/2/JPEE201.pdf), 5th Portuguese Conference on Structural Engineering.
- J. Sampaio, [Análise do comportamento sísmico de elementos não estruturais de alvenaria](https://repositorio-aberto.up.pt/bitstream/10216/128612/2/412786.pdf), FEUP, July 2020.
- Decreto-Lei n.º 95/2019, of 18 July, [consolidated version published by the Câmara of Almodôvar](https://cm-almodovar.pt/wp-content/uploads/2020/01/dl95_2019_Vset2019.pdf), September 2019.
- Portaria n.º 302/2019, of 12 September, [copy of the Diário da República](https://www.dec.fct.unl.pt/sites/www.dec.fct.unl.pt/files/documentos/portaria_302_2019.pdf).
- Despacho Normativo n.º 21/2019, of 17 September, [copy of the Diário da República](https://www.dec.fct.unl.pt/sites/www.dec.fct.unl.pt/files/documentos/despacho_normativo_21_2019.pdf).
- Câmara Municipal de Amarante, [Relatório de avaliação de vulnerabilidade sísmica: como atuar](https://www.cm-amarante.pt/wp-content/uploads/2025/01/Relatorio-de-avaliacao-de-vulnerabilidade-sismica-bem-como-as-situacoes-em-que-e-exigivel-a-elaboracao-de-projeto-de-reforco-sismico-%E2%80%93-Como-atuar.pdf), January 2025.
- Decreto-Lei n.º 555/99 (RJUE), articles 89 and 90, [PGDL consolidated version](https://www.pgdlisboa.pt/leis/lei_mostra_articulado.php?nid=625&tabela=leis).
- Government of Portugal, [PTRR cria fundo de catástrofes e avança com seguros obrigatórios](https://portugal.gov.pt/pt/gc25/comunicacao/noticias/ptrr-cria-fundo-de-catastrofes-e-avanca-com-seguros-obrigatorios), 28 April 2026.
- Unofficial reference: ECO Seguros/Lusa, [Câmara de Lisboa avaliou a vulnerabilidade sísmica de 1.593 edifícios](https://eco.sapo.pt/2025/06/17/camara-de-lisboa-avaliou-a-vulnerabilidade-sismica-de-1-593-edificios), 17 June 2025.

## FAQ

### What should I do during an earthquake if I am at home?

The ANEPC asks for three gestures: drop down, protect your head and neck and wait until the ground stops shaking. Shelter by a beam or pillar, in a corner or under a sturdy table, away from windows. Do not rush to the stairs or use the lift.

### After an earthquake, can I climb onto the roof to see the damage?

It is not a good idea. The ANEPC warns there may be aftershocks and says to leave the house if there is serious damage or a risk of collapse. Look from a distance and call a civil engineer if you see new cracks, a twisted chimney or tiles on the ground. In an emergency, call 112.

### Does replacing the roof with a lighter one make the house earthquake-resistant?

Not on its own. Weight matters, but so do the connections between walls and roof, tie rods and the condition of the walls. Changing the weight may change the structural behaviour, which under Portaria n.º 302/2019 may require a seismic vulnerability report. Talk to an engineer first.

### When do works need a seismic vulnerability report?

Under Portaria n.º 302/2019, in alteration, extension or reconstruction works with clear evidence of structural deterioration, a change in structural behaviour, an area of works above 25% or a cost above 25% of an equivalent new building. Repairing as it was is conservation work.

### Is there aid for seismic strengthening of a house?

We found no national programme. The fund announced by the Government in April 2026 is about catastrophe insurance. In Lisbon, according to Lusa (June 2025), the ReSist programme was due to launch technical support for private buildings in 2026, which we did not confirm.

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Source: https://telhadoseguro.pt/en/guides/earthquake-roof-home-safety. Independent information, not legal or tax advice.