Damp and water damage in a house that stays closed for months

Three different kinds of damp, each with its own culprit

Condensation is the most common in a closed house. Air carries water, and when it touches a cold surface it leaves it there: on the glass, in the corners of ceilings, behind furniture pushed against an outside wall. Without ventilation that water does not leave, and mould appears as black patches and dots, usually high on the walls and in corners.

Rising damp climbs from the ground through the walls of a ground floor. You recognise it by a band at the same height along the wall, sometimes with white salts and blistering paint. It does not depend on the house being open or closed, but a closed house lets it advance with nobody seeing.

Seepage and leaks are water getting in: through a terrace whose drain is blocked, a roof, a pipe or a flexible hose that gives way. They leave a stain that grows from a point, and they are the only one of the three that can do a lot of damage in a few days.

Why a closed house fills up with damp

Because the three things that encourage it happen at once: shutters down, windows shut and nobody cooking, showering or running the heating. The house stops renewing its air, and the moisture coming from the ground, the walls or the coastal climate stays.

What you notice on return, the closed-up smell, clothes in the wardrobe smelling damp, mould on the bathroom ceiling, did not happen on the last day: it had been spreading for weeks. That is why damp is measured during the absence, at the same spots and with the same instrument, and not smelled on arrival.

Three things help before leaving and cost nothing: leave a ventilation gap in the shutters if the house is damp, move furniture a few centimetres away from outside walls and leave the wardrobes ajar. Damp absorbers and a dehumidifier with a continuous drain do the rest.

The day someone finds a leak: the order of things

First, close the main stopcock, even if the leak looks small. The law requires the insured to use the means within reach to reduce the consequences of the loss, and if they do not, the insurer can reduce what it pays. Turning off the water is the first of those means, and the cheapest.

Second, photos, before touching anything: the stain, the source if visible, the furniture and floors affected, the meter. Dated, from several angles. Nothing damaged should be thrown away before the loss adjuster sees it, except what cannot wait, and that gets photographed first too.

Third, notify. Your insurer, through the channel your policy states. The neighbour below if the water has reached them, and the one above if it comes from them. And the community's property manager if the source may be a shared downpipe, facade or roof.

Seven days to notify your insurer, from when you know

The Spanish Insurance Contract Act states that a loss must be notified to the insurer within a maximum of seven days of becoming aware of it, unless the policy allows longer. If notice is late, the insurer can claim the damage the delay has caused it.

For an empty house the rule has a practical consequence: the period runs from when someone knows what has happened. The sooner someone goes into the house, the sooner it is known, the sooner the water is off and the less the damage grows. A leak that runs for three months is not three times a one-month leak: it is a ceiling, a floor and a wardrobe.

And it is worth reading beforehand, not afterwards, what your policy says about an unoccupied home. Some change their cover when the house stays empty for many days in a row, or require periodic visits. There is no general rule: it is in your contract, with your number of days.

Who is responsible for what: you, your neighbour, the community

Every owner must keep their home and its installations in good repair, and make good the damage caused by their negligence: the Horizontal Property Act says so. If water comes out of a pipe in your home and reaches the neighbour below, your side is responsible, and normally your insurance. If it comes down from the flat above, theirs is.

If the source is a common element, a main downpipe, the roof, the facade, upkeep is the owners' community's job, and the claim goes through the property manager. Where the water comes from is therefore the first question, and sometimes it takes a specialist to answer it.

Torrential rain is another matter. An extraordinary flood is not covered by your policy in the usual way but by the Consorcio de Compensación de Seguros, provided the home has insurance in force. The Vega Baja has known this since the DANA storm of September 2019. A terrace with its drain cleared before autumn prevents, to begin with, the seepage that is no catastrophe and that no insurer treats as extraordinary.

What this guide cannot tell you

What your policy covers, within which deadlines and with what excess: that is in your contract and varies from one insurer to another. Whether the stain on your wall is condensation, rising damp or a hidden leak: sometimes it shows, sometimes it takes a specialist with instruments that are not ours. And what it costs to fix.

What we can do is go into your house, measure, photograph and leave you a file ready for your insurer or your specialist to understand first time. And, before all that, close it properly on the day you leave.

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The other guides

Official sources

• Spanish Official Gazette · Insurance Contract Act, Law 50/1980
• Spanish Official Gazette · Horizontal Property Act, Law 49/1960
• Insurance Compensation Consortium (Consorcio de Compensación de Seguros)