How cold does it have to go before......

[alittlebitfrench]

How cold does it have to go before your pipes start freezing .....inside the house ?

Our house (in the best city in France) has the heating and water turned off and the house is very well/quite well insulated.

So how cold does it have to go outside to freeze the pipes inside the house ? Thinking radiators and other pipes.

Can pipes freeze and burst that are buried in walls and the floor ?

Many thanks in advance for any input on this worrying matter.

P.S It is really not me. Leave them alone.

[Chancer]

It is time dépendant, also if you have adjoining dwellings that may be transferring some heat to your dwelling.

 

Its below zero overnight here but gets above zero during the day, that is unlikely to burst pipes in a dwelling like yours, if it is constantly below zero than after a few days you might have a problem, if it drops to say minus 15° celcius then you may have a pipe burst within 24 hours, if it is minus half a degree over a long enough period that will burst a pipe in an uninsulated house.

 

Wind chill also has an affect.

[Patf]

Our daughter in SE England has had a burst in one of her copper pipes . She's claiming from her house insurance for the various damages.

Here, inside we have only plastic pipes, does that make a difference?

[andyh4]

Plastic pipes (in theory at least) have more stretch and give than copper and therefore should be more resistant to freezing. However the push fit joints may be a point of weakness if the pipes freeze.

ALBF - pipes buried in the walls and floor are not immune to freezing. The floor inside is likely to be better protected than just about anything else, since the inside of the building would need to be below freezing for a length of time and be able to suck heat out of the floor faster than the surrounding earth can feed heat back in. Walls may be more susceptible - especially north facing ones which do not get direct sun radiation during the day.

However given the wrong conditions you will need a heat source to ensure there is no freezing. To make the point back in February 2012 we had a period where the daytime high temperatures for 10 days or so did not get above -8 C (most nights below -15 C). This was coupled by fairly high winds - so wind chill - but no precipitation - so no snow cover on the ground. [Snow is a surprisingly good insulator.] Our heating system coped well and kept the house warm and pipes a long way from freezing. However that did not apply to the water main feeding the house, which froze. We had no mains water for 19 days until the daytime temperatures had been above zero for nearly a week.

The main was plastic pipe and did not burst (note above for Patf.)

[Loiseau]

albf, we always used to turn off the water and drain down the system when we left our previous holiday house.

We had a problem just once. Arrived, turned on supply, then - shock - water pouring through ceiling from upstairs bathroom!

On investigation, we found that the ceramic lavatory cistern had fractured during a very cold spell, so water was spraying everywhere.

Since then, we always made a point of flushing the WCs on departure after turning off the water, to make sure no water was left in them. And we fitted a plastic cistern to replace the ceramic one,

Angela

[Harnser]

A bit of a nit-pick.

Wind chill does not alter the actual air temperature affecting a water pipe or tank.

It is the the perceived decrease in air temperature felt by the human body on exposed skin due to the flow of air.

[andyh4]

You are right Harneser - but only up to a point.

Wind chill causes evaporative cooling as well which reduces the temperature of the surface from which the material evaporates. But you are right, the air temperature does not change. Now of course you are going to tell me that at minus whatever there is no liquid (water) to evaporate, but in the case of water ( as a frost covering) this is able to change from solid to vapour below zero. In this case the heat loss is not only the latent heat of evaporation but also the latent heat of melting - so a double whammy.

This is the reason why frosts form when air temperatures do not fall below zero.

[alittlebitfrench]

Thanks all.

I was in two minds of what was best to do when we left a couple of days ago given that Tours does not really get that cold, but it seems we have a cold spell looming. There was a cold spell about 6 years ago and temperatures remained below freezing for a good two or three weeks.

The house is very well insulated and has proper double glazing but I don't want any hassle with a burst pipe.

Question.....

Does a gas boiler (modern dietrich) need the water supply turned on in the house in order to operate ?

What I want to do is run the radiators at a low setting but not heat the water.

Can I do that and if so how ? Or will the computer say no ?

[Leven]

It does not get cold in Tours your having a laugh. If its that hot why do the outside cafes have exterior heaters. Happy new year btw

[alittlebitfrench]

Hi Lev

It does get cold in Tours......well sometimes. We had snow the other day for the first time in ages. Well a dusting.

Cafes are certainly warmer in Paris than my homeless shelter. Beer is expensive mind you but you are warm. BTW that was not me....so another new member bites the dust. WTF must they think of you lot of muppets with their first posting. LOL

PS. I hope business perks up for you in 2017. If not you could become an AE labourer advertising your services on AI. My roof needs some help if you get desperate.

Happy New Year to you to.