Frost damage and heating failure

01How does a water pipe actually freeze?

Water expands when it freezes. Inside a pipe there is no room for that, so the pressure rises until the pipe or a joint cracks. The nasty part is that you cannot see the crack while it is still freezing: the ice holds the water back. Only when the pipe thaws does the water escape, often somewhere nobody looks.

How fast a pipe freezes cannot be captured in one number. Wind, frost in the ground, the position of the pipe and its insulation decide it together. Sometimes it takes a few days for the frost to get in, sometimes it happens within a day. That is why fixed rules of thumb such as "only at minus ten" do not work. What is certain: the colder the space around the pipe, the higher the risk.

Where it usually goes wrong

Outdoor taps and garden pipes that have not been shut off and drained.
Pipes in the crawl space, especially with open air vents and no pipe insulation.
Pipes along or inside an outside wall, in an unheated utility room, shed or garage.
The water meter and main stopcock, if they sit in a cold, draughty space.
Empty rooms and empty houses, where the heating is low or off and nobody notices a problem.
The central heating pipes themselves: if the boiler fails, the water in the heating pipes and radiators can freeze too.

02What does a heating failure in winter mean?

A heating failure in winter is more than an inconvenience. For residents, the house gets colder every hour. In shared housing people often sleep in small rooms on an outside wall, and those rooms are the first to get cold. Residents then quickly reach for a plug-in electric heater, with a high electricity bill and sometimes overloaded sockets as a result (see our article on plug-in heaters and electricity costs).

For the building there are two risks. The first is freezing: of the heating pipes, the water pipes and the water meter. The second comes later and is often forgotten: moisture. When walls and floors have been cold for days, the moisture from showering, cooking and breathing condenses on them as soon as the house is lived in again. Residents keep windows shut to stay warm, so that moisture cannot escape. A few cold days can show up weeks later as black patches behind a wardrobe. How that works is explained in preventing mould in worker housing.

A heating system that does not give enough heat is also a defect under Dutch tenancy law. In its policy book, the Huurcommissie (rent tribunal) states that with an outside temperature of -10 °C it must be possible to reach 20 °C in the living room and 18 °C in a bedroom.

03Who pays for frost damage: landlord or tenant?

The main rule in Dutch tenancy law: the landlord repairs defects, the tenant does minor repairs. Those minor repairs are listed in the Besluit kleine herstellingen (Minor Repairs Decree). According to the Dutch government, preventing taps from freezing is one of them, as are bleeding, topping up and restarting the central heating. Repair, inspection and replacement of technical installations in the home are for the landlord.

For damage to the house itself, article 7:218 of the Dutch Civil Code also applies. It says the tenant is liable for damage caused by failing to meet an obligation under the tenancy agreement, where that failure can be attributed to them. If a resident left the outdoor tap open after a clear instruction, the situation is different from a poorly insulated pipe in a wall that freezes while the heating was on as normal.

And insurance?

Buildings insurance (usually the owner's): frost damage to pipes, a broken water meter or a frozen heating pipe is covered in most cases. A common exception is damage caused by poor maintenance or by not taking precautions.
Water meter: water companies charge the cost of a frost-damaged meter to the customer.
Residents' belongings are not covered by the owner's buildings insurance. Check the terms of your own policy, including for a house that stands empty.

This article is general information and not legal advice. What applies in your situation depends on the contract, the policy and the facts. If in doubt, consult a lawyer or your insurer.

See a cold house before there is water on the floor

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04Checklist: how do you prevent frost damage?

Almost all measures are cheap and take little time. What matters is that they happen before the first frost, and that someone is responsible.

In every house, every autumn

Shut off and drain outdoor taps. Close the valve inside and open the outdoor tap so the remaining water runs out.
Insulate vulnerable pipes in the crawl space, the utility room and along outside walls, with pipe lagging or, where needed, trace heating.
Keep the space around the water meter and stopcock draught-free and as well insulated as possible.
Know where the main stopcock is, and show the residents too.
Have the heating system checked and the water pressure tested, so the boiler does not fail halfway through winter.

Occupied houses

Agree that in frost the thermostat does not go below 14 °C, at night as well; that is the advice of water company Vitens.
Keep the radiators in every room open, including rooms that are temporarily unused.
Give a short instruction in the residents' languages: outdoor tap closed, windows not wide open at night in frost, report a fault straight away.

Empty houses and holiday periods

Do not switch the heating off. Univé advises between 12 and 15 °C when nobody is home.
For longer vacancies, consider shutting off and draining the water supply.
In frost, have someone check the house regularly, or measure the temperature remotely.
Check your policy for what applies to empty properties.

05What do you do when a pipe has frozen or burst?

Close the main stopcock. That is always the first step, even if you cannot see a leak yet.
Look for a crack or leak. If you find one, call a plumber before you start thawing. Otherwise the water escapes as soon as the ice melts.
Thaw gently. Warm up the space, use a hairdryer or a cloth soaked in warm water. Do not use an open flame.
Switch off electrical appliances and the power in the wet area if water comes near sockets.
Record the damage with photos and times, and report it to the insurer as soon as possible. Report a frozen water meter to the water company.
Make sure residents stay warm while the heating is not working, and agree who comes back and when.
Dry the house properly afterwards: heat and ventilate, so no mould grows in walls and floors.

Situation	First step	Who to call
No water, no visible leak	Stopcock closed, warm the space	Plumber if it does not thaw
Water from wall, floor or ceiling	Stopcock closed, power off in that area	Plumber, then insurer
Water meter frozen or broken	Stopcock closed	Water company
Heating down during frost	Check pressure and fault code on the boiler, restart once	Heating engineer or landlord

06How can you see it coming before the damage is done?

The biggest problem with frost damage is time. A boiler fails on a Friday evening, the residents work shifts, and nobody calls. Or the house is empty between two groups of residents. The first report then only comes when water drips through the ceiling.

With a temperature sensor in every room you see the pattern earlier: all rooms cool down at the same time while it is freezing outside. That is the signature of heating that has stopped working, and it is different from one room where a window is open. eyesonrooms measures temperature and humidity per room and raises an alert for a room that gets too cold and for a house where the heating does not seem to be working. Every morning at 07:30 it is in one summary email, so a coordinator can visit the same day.

The same readings help afterwards. You see whether the house gets back up to temperature after a fault, and whether humidity in the rooms stays high for days. That is the moment to ventilate, before the moisture from the cold spell turns into mould.

07What should you agree with residents and management?

Technology helps, but most frost damage starts with unclear arrangements. Write down:

Who does the autumn round: outdoor taps, insulation, boiler check. Put it in the schedule, with a date per house.
Who takes a fault call, including at weekends, and within what time someone visits.
How residents report: a phone number or a QR code in the house that works in their own language, so a cold room is not only discovered days later.
What residents may do themselves: top up and restart the heating following instructions, but not work on pipes or gas connections.
How you record a report: time reported, time fixed and what was done. That helps with the insurer, and in any discussion about who is liable.

If the landlord does not fix a defect, a tenant can start proceedings with the Huurcommissie. After written notice the landlord first gets six weeks. Under article 7:206 of the Dutch Civil Code, the tenant may have a defect fixed themselves if the landlord is in default, and recover reasonable costs. For a house without heating in the middle of winter, waiting is obviously not a good idea; acting fast also prevents the bigger damage.

08Frequently asked questions

At what temperature does a water pipe freeze?

There is no fixed number. Wind, frost in the ground, where the pipe runs and its insulation together decide how fast a pipe freezes. Pipes in cold, draughty spaces such as the crawl space or an outside wall are most at risk.

How low can the thermostat go in frost?

Water company Vitens advises keeping the heating at a minimum of 14 °C in frost, also in night mode. Insurer Univé advises 12 to 15 °C when nobody is home.

Is shutting off the outdoor tap the tenant's job?

Preventing frozen taps is one of the minor repairs that, according to the Dutch government, fall to the tenant. Do agree it clearly and give instructions, especially when residents change often.

Does buildings insurance pay for a burst pipe?

In most cases, yes. A common exception is damage caused by poor maintenance or by not taking precautions. Always check the terms of your own policy.

Can I tell the heating has failed without anyone calling?

Yes, if you measure the temperature per room. When all rooms cool down together while it is cold outside, the heating is probably not working, and you can act the same day.

Preventing frost damage and heating failure in rented housing