how cold does it have to be to worry about frozen pipes in the house

[steveo3002]

planning to try and use alot less heat this year , was wondering what sort of outside conditions does it have to be before worrying about pipes freezing up

loft is insulated anyway so i doubt its very warm up there , most of the pipes are lagged

 

[brightspark]

just dont leave the house empty for a few weeks or you wont be insured for bursts if the pipes are lagged in the roof voids nothing to worry about

 

[Barking Mat]

Keep it above freezing.

Or drain it down.

I winterise all our boats to -20 just in case, no heating or insulation, drained down, water circuits blown out with compressed air.

Engines and central heating circuits checked with a antifreeze gauge.

You sleep better.

 

[Bornfree]

Well lagged loft pipes and internal pipes are normally good to -4-5

 

[optima21]

if you have water in your attic, the pipes up there can freeze as the loft insulation can keep the heat in the house but out of the attic. on the pipework to my water tank (old style vented system rather than combi boiler) I have a frost thermostat set a 3C and thats located on the coolest part of the attic, and then run heated wire along the pipes.

I did buy an electronic frost thermostat and in the instructions it did say not to use below 5C (as in its working temperature, not what it was measuring), so now I use a mechanical one.

ohh and frozen pipes aren't anything to worry about, it when they thaw afterwards

 

[steveo3002]

Well lagged loft pipes and internal pipes are normally good to -4-5

and the loft would still be a few deg warmer than outside too?

my loft tank and most pipes are directly above the emmersion heater so i guess a little bit of heat travels up

 

[mike os]

You want a minimum working temp of 5-7c

Below that you run a risk of freezing ..,

 

[merryman]

When I lagged the loft, the instructions I got said to leave the underside of the tank un-insulated and cover the tank with insulation. I used cosywrap for the floor but bought a big polysyrene sheet and made a box to enclose the tank (underside excepted. I would have thought any decent installer would do the same. As the tank is directly above the hot water tank, it is not going to freeze, as long as there is some heat in the hot water tank below, to leak upwards. Downstairs toilet is in a porch by the back door and regularly freezes in winter. I sometimes put a 6 pint milk bottle full of hot water beside the pipe where it comes through the floor, before going to bed, if the temp gets below freezing outside, doesn't always work though.

 

[arther dailey]

When I lagged the loft, the instructions I got said to leave the underside of the tank un-insulated and cover the tank with insulation. I used cosywrap for the floor but bought a big polysyrene sheet and made a box to enclose the tank (underside excepted. I would have thought any decent installer would do the same. As the tank is directly above the hot water tank, it is not going to freeze, as long as there is some heat in the hot water tank below, to leak upwards. Downstairs toilet is in a porch by the back door and regularly freezes in winter. I sometimes put a 6 pint milk bottle full of hot water beside the pipe where it comes through the floor, before going to bed, if the temp gets below freezing outside, doesn't always work though.

for your outside carsy one of those greenhouse parafin heaters will do fine on the coldest of nights, small upright thing ,not the big ones

 

[RaceDiagnostics]

planning to try and use alot less heat this year , was wondering what sort of outside conditions does it have to be before worrying about pipes freezing up

loft is insulated anyway so i doubt its very warm up there , most of the pipes are lagged

I think you'll get hypothermia before the pipes freeze.

 

[8ob]

The answer to the question is kin cold, if it’s that kin cold the heating will be on so pipes freezing won’t be an issue.

Bob

 

[steveo3002]

I think you'll get hypothermia before the pipes freeze.

yeah sort of thinking the same ..if its super cold then you need heat on

 

[Morrisman]

My dads house is sitting empty, but i've left the CH at 12° just to keep the damp and cold away.

 

[mart]

if you have water in your attic, the pipes up there can freeze as the loft insulation can keep the heat in the house but out of the attic. on the pipework to my water tank (old style vented system rather than combi boiler) I have a frost thermostat set a 3C and thats located on the coolest part of the attic, and then run heated wire along the pipes.

I did buy an electronic frost thermostat and in the instructions it did say not to use below 5C (as in its working temperature, not what it was measuring), so now I use a mechanical one.

ohh and frozen pipes aren't anything to worry about, it when they thaw afterwards

Good detailed advice here from Optima21.

Please would you post the detail on here of your mechanical thermostat, and also the heated wiring you run along the pipe. Also, the supplier of the parts if you don't mind please.

I have the same heating system as Optima21, no combi and the tanks & pipes are in the loft. I believe it was 2011 January and the temp outside dropped to minus 7 degrees. My pipes in the loft froze, and when they thawed I had water running down the wall of my stairs. This was the year when people's condensate pipe from their combi boiler was freezing up. That stopped the boiler working if fully blocked by ice.

When the temp drops very low outside I open the loft hatch to let warm air from below rise in to the loft. It is a PITA with this system.

 

[Robotstar5]

for your outside carsy one of those greenhouse parafin heaters will do fine on the coldest of nights, small upright thing ,not the big ones

I remember my dad hanging one of those under the bonnet of his car to stop the block freezing in the 60's.

 

[Shox Dr]

The answer to the question is kin cold, if it’s that kin cold the heating will be on so pipes freezing won’t be an issue.

Bob

...when I wer a lad....

In the late 70s we lived in a shed for 3yrs while my dad built a house. It was made of 1/4" Asbestos on 4x2 battens. No insulation at all, and one electric fire in what was the kitchen. I could wake in the morning to a frozen glass of water it was that cold, same with the toilet. The pipes would be frozen for days on end at times. Though we only ever had one bust pipe. My dad said it was because he opened all the taps as soon as they froze, allowing the expanding ice somewhere to go.

 

[8ob]

...when I wer a lad....

In the late 70s we lived in a shed for 3yrs while my dad built a house. It was made of 1/4" Asbestos on 4x2 battens. No insulation at all, and one electric fire in what was the kitchen. I could wake in the morning to a frozen glass of water it was that cold, same with the toilet. The pipes would be frozen for days on end at times. Though we only ever had one bust pipe. My dad said it was because he opened all the taps as soon as they froze, allowing the expanding ice somewhere to go.

I remember living in houses where you opened windows to let some heat in.

Bob

 

[JimmyS]

Other thing you can do is leave a tap dripping, well we can in Scotland at least as no water meters to worry about. Takes a lot longer for a pipe to freeze if theres a trickle of water passing through it, even if just cold water.

 

[mart]

for your outside carsy one of those greenhouse parafin heaters will do fine on the coldest of nights, small upright thing ,not the big ones

Or a candle secure enough to not fall over, and away from anything combustable.

 

[fizzy]

When I was 17 my mother died. This left my brother and I destitute. We had no money for any heating at all. House very badly insulated and no double glazing. We lived like that for 3 years. I literally mean no heating at all. We had some very cold winters indeed. Sometimes there was ice on the walls inside the house. We never had any burst pipes or anything. Very grim times still haunts me to this day - that is why I always have a woodburner now - can always scrounge wood.