Frozen Pipes in Biggin Hill: Winter on London's High Ground

Biggin Hill is one of the highest parts of London, rising above 210 metres, so frosts bite harder and snow settles more often than down in Bromley town centre. To stop pipes freezing, lag everything in the loft, garage and outbuildings, insulate over the loft tank but not under it, drain outside taps and any supply to sheds or studios, and keep the heating on low through cold nights. Then make sure you know where both your stopcock and your outside stop tap are, because if something does split, it floods when it thaws.

Why Biggin Hill is different

Most of the borough sits well below 100 metres. Biggin Hill rises to over 210 metres, the Met Office station there is listed at 176 metres, and Westerham Heights just to the south, at 245 metres, is the highest point in Greater London. Height means colder nights and more exposure to wind.

The housing makes it worse. Biggin Hill grew from 1920s and 1930s plotlands into a valley of bungalows, chalets and self-built houses, extended and rebuilt piecemeal ever since. Bungalows and chalets have big, cold roof spaces with tanks and pipes in them. Many plots have garages, workshops, garden rooms and outbuildings with a water supply run out to them, often in a shallow trench or along an outside wall. Every one of those is a pipe exposed to the cold.

Where do pipes freeze first?

• The loft, especially the pipe that fills the tank and the overflow pipe, and pipes in the eaves of chalet bungalows.
• Garages and lean-tos, where a washing machine or sink has been plumbed in on an outside wall.
• Outbuildings and garden taps, fed by a pipe across the garden.
• Under suspended floors where air bricks let the wind through.
• Where the supply comes into the house, if it rises through an unheated space.

The autumn checklist

1. Lag every exposed pipe in the loft, including bends, joints, valves and the overflow, with proper foam pipe insulation.
2. Fit a jacket or insulated lid on the loft tank, and keep loft insulation out from directly under it so warmth from below can reach it.
3. Lag pipes in the garage, utility room and any outbuilding.
4. Find the isolating valve for each outside tap and outbuilding supply, turn it off, then open the tap at the far end to drain the pipe, and leave it open.
5. Check the condensate pipe on the outside of a condensing boiler; if it freezes the boiler stops, which is a boiler matter for a Gas Safe registered engineer or the manufacturer’s guidance.
6. Find your inside stopcock and check it turns.
7. Find your outside stop tap, usually near the boundary, and make sure you can lift the cover. On a long Biggin Hill plot it may be a long way from the house.
8. Set the heating to come on low through the night in a cold spell rather than switching it off.

What do I do if a pipe freezes?

Thames Water’s advice, which supplies Biggin Hill, is straightforward. Turn the stopcock off by turning it clockwise; it is usually under the kitchen sink. Open the taps. Thaw the frozen pipe slowly, with a hot water bottle or towels soaked in warm water, starting at the tap end. Never use a naked flame. Before turning the water back on, run a dry cloth along the pipe to feel for a split.

If water is already coming through a ceiling, keep the stopcock off, switch off the electrics in that room at the consumer unit, and call.

What if the house or annexe is empty?

Empty buildings freeze fastest, because nothing is warming them and nobody notices until the thaw. If a granny annexe, studio or holiday let on your plot will sit empty in winter, either keep it heated on a frost setting or turn its supply off at its own isolating valve and drain it down by opening the taps. Check your insurance policy too: many have conditions for homes or buildings left unoccupied in cold weather.

What about Thames Water’s main works?

Thames Water is replacing 3.9 kilometres of water main in Biggin Hill, along Main Road and Leaves Green Road, with work running to September 2027. Bromley Council reported that there had been 25 burst mains in five years on that stretch. During the work, supplies may be switched off for a time, normally with a letter first. If you have no water and the neighbours have none either, check Thames’s postcode incident map before assuming your own pipes have frozen.

Does a long supply pipe freeze?

The supply pipe under your garden should be laid deep enough to avoid frost, but older plotland pipes were laid by whoever built the house, and some are shallow, especially where they rise to a stopcock or run to an outbuilding. If one part of the house always freezes first, it is worth having the route checked. Our guide to a leak on a long private supply pipe in Biggin Hill covers what happens when one of those pipes fails.

The same high-ground problem catches houses on the Norwood Ridge, and our guide to frozen pipe prep in Crystal Palace covers tall Victorian lofts. More about TN16 on our Biggin Hill page.

Need a plumber now?

If a pipe has frozen and split, or water is coming through a ceiling, Call 07868 281022. Tell us your postcode, what is leaking or frozen, and whether the stopcock is off. We cover frozen pipes in Biggin Hill and burst pipes across TN16 on the Bromley side, including Leaves Green, Downe and Keston, and we agree the price with you before any work starts.