Floods and earthquakes: how much a house is at risk and what insurance covers

In our sample report on a building in Rimini, in an area that floods roughly once every 30 years, floods and earthquakes cost on average between 640 and 2,020 euros of damage a year for a 100 square metre home. At a point in Milan outside the flood zones the same figure drops to 20-25 euros, almost all of it from earthquakes. Two ordinary homes, two very different risks, and in both cases insurance is the household's own choice.

Average annual damage

In most years a flood or an earthquake does not touch a house at all. Now and then one arrives and does heavy damage. Average annual damage puts the two together: it adds up every possible level of damage, from light to severe, and weights each by how likely it is. The result is a figure in euros a year, the same quantity insurers start from when they price a premium, before adding their costs and margin.

In our report the calculation follows the European seismic risk model ESRM20 and the damage curves of the European Commission's Joint Research Centre (JRC), combined with official Italian hazard data: the flood zones of the plans collected by ISPRA and the INGV earthquake map MPS04. The starting point is what it would cost to rebuild a 100 square metre home. The European model uses 1,300 euros per square metre in Milan and Rome, 1,000 in municipalities with more than 10,000 inhabitants and 900 elsewhere, at 2020 prices; the report brings these up to date with the Istat construction cost index.

The result is always a range. For water, where the European model does not know the expected depth, the report tries everything from 20 centimetres to one metre. For earthquakes it runs from the sturdiest to the most fragile building types in the municipality, because open data do not say how an individual house was built. A recent earthquake-resistant block sits towards the bottom, old masonry towards the top.

In Rimini, in the sample report, earthquakes account for 220 to 340 euros a year and the rest comes from water. In total, against the cost of rebuilding, that is between 0.5% and 1.6% a year. In Milan, outside the flood zones, it is around 0.1 to 0.2 per thousand.

Reading it next to a quote

An insurance premium will normally be higher than the average damage, because it also carries the insurer's costs and profit. The comparison tells you the order of magnitude. If the average damage is a few euros and the quote is a few hundred, you are mostly paying for peace of mind against a rare event. If the average damage runs to hundreds of euros, as in areas that flood often, a similar premium simply reflects the risk of the place.

There is a second way to look at the same number. An average of 1,000 euros a year does not arrive a little at a time: when it comes, it comes as a bill of tens of thousands of euros in a single year. The useful question is how much of that bill you could pay yourself.

Some things are left out of the calculation and are worth remembering when you read a quote:

• furniture, appliances, cars and stock: the report counts only the building;
• landslides, because no open model says what they cost on average (the report says separately whether the ground is in a landslide risk area);
• the individual flat: the figure is for a reference 100 square metre home at that point, and cellars and ground floors flood before upper floors do.

The legal duty to insure applies to businesses

Italy's 2024 budget law (legge 30 dicembre 2023, n. 213, article 1, paragraphs 101 onwards) made insurance against natural disasters compulsory for businesses based in Italy, or with a permanent establishment in Italy, that must be entered in the companies register (registro delle imprese). They must insure the assets carried on their balance sheet as fixed assets: land and buildings, plant and machinery, industrial and commercial equipment. Paragraph 101 lists five events: earthquakes, floods, landslides, inundations and rivers bursting their banks. The value to insure is the cost of rebuilding as new.

Paragraph 104 caps the excess on these policies at 15% of the loss, except for large companies. Paragraph 106 says insurers only have to cover buildings built or extended with valid planning permission, or regularised under an amnesty, and that buildings which cannot be insured get no public grants after a disaster. According to the Ministry of Enterprises and Made in Italy (MIMIT), farms are excluded, and deadlines were staggered by company size starting from 31 March 2025, with later postponements for some sectors.

For households the law sets no obligation. If you buy a home to live in, insuring it is up to you. If the property is bought by a company entered in the companies register and goes on its balance sheet, the obligation does apply.

What to read in the policy

Cover for natural disasters is often one part of a multi-risk home policy, and every contract words it its own way. Before signing it is worth checking, in writing:

1. Which events are covered. Earthquake, flood and landslide may be separate items; also read how the contract defines flooding and water damage.
2. The excess, meaning the part of the loss you bear yourself, and the maximum payout per event or per year.
3. The value the house is insured for. The reference is the cost of rebuilding it, which is not the price you paid or the market value of the area.
4. Whether contents are included, and up to what amount.
5. In a block of flats, what the building's policy covers. Not every condominium policy covers flood damage: ask the building manager (amministratore) for it before the preliminary contract, together with the minutes of recent meetings.

Tax relief

For policies against natural disasters on homes and their appurtenances, taken out from 1 January 2018, 19% of the premium can be deducted from income tax (article 15, paragraph 1, letter f-bis of the income tax code, TUIR). According to the Revenue Agency (Agenzia delle Entrate) guide to the 2026 tax return, this also applies to your share of the condominium's policy for your flat, certified by the building manager. In multi-risk policies only the part of the premium covering disasters counts. Payment must be traceable, and above certain incomes the deduction shrinks: the thresholds are in the guide.

Where to start

Type the address on the site: you immediately see, for free, the liveability index of the area. In the full report the block "What floods and earthquakes cost on average" gives the range in euros a year, splits the water part from the earthquake part and shows the rebuilding cost used. The method is explained in What floods and earthquakes cost.

To see where the two halves of the figure come from: Flood zones P1, P2 and P3 explained, Seismic zones 1, 2, 3 and 4 explained, and the pages House in a flood zone and Seismic zone of a house. The other checks are in What to check before buying a house in Italy.

Sources

Pages consulted on 26 September 2026:

• Legge 30 dicembre 2023, n. 213, article 1, paragraphs 101-107, text on Normattiva.
• Ministero delle imprese e del made in Italy, polizze per rischi catastrofali, page updated on 3 June 2026.
• Agenzia delle Entrate, Tutte le agevolazioni della dichiarazione 2026: premi di assicurazione.
• European seismic risk model ESRM20 and JRC damage curves.