Frozen pipe!

[Jlo]

I've got to fix a frozen pipe in the loft of a chapel tomorrow. Its a relatively modern building, well lagged pipes etc. The chapel is only brought up to temperature when services are held, and it seems the extreme cold we had a few days ago got to the mains feed to the ball cock valve. There is a frost stat set to 5oC in the toilet.
Any ideas as to how to stop this happening again? I'm not religious myself so praying won't help!

 

[Mike Jackson]

Trace heating.

 

[Nostrum]

Lagging?

 

[scotty plumber]

Plenty laggingon pipes, pack-up any draughty holes with insulation or foam, check if there are any air-vents close to where pipe is freezing as this often happens to me

 

[Nostrum]

25mm armorflex should sort it out, Its what we use on external oil boilers and they've been alright for the last 2 years. Just make sure you do a good job at fitting it.

 

[Mbear]

Fit a sure stop so the minister can isolate the water easily and then tell him to open the taps to drain off pipework when it's not in use

 

[Best]

If it is possible to isolate the pipes & tank in attic from the outside, that will help. Even a few uprights & a polythene sheet keeps it apart from rest of attic. A thermostatic electric tube heater may then keep it safe. Obviously 25mm insulation needed. Insulation on roof great, but I know this not your issue.

 

[SimonJohns]

More lagging the better and thicker the better. But it all comes down to installation. Tape all joins. Use a rubberised or foam lagging rather than the fibreglass. The fibreglass will retain water and be more prone to freezing if they become damp.

 

[WHPES]

If theres no heating inside the building, then insulation will only buy you a couple of hours before the pipe inevitably freezes anyway.

 

[peteheat]

Maybe a step back thermostat would help, they can be timed to work at low and prefered temperatures, the building can be kept at a minimum say 12 degrees when closed and timed to increase the temperature to say 19 when in use.

One benefit is the building is not starting to heat from a very low temperature so will heat up faster using less time and fuel, also the warmer the water is the faster it freezes so switching off a hot system in very cold weather will cause it to freeze.

Have you checked if the pipe is over the attic insulation? I came across a similar problem that was solved by lifting the fibreglass over the pipe allowing some heat from the building to protect the pipes, similar to not lagging under the cold water storage tanks.

 

[Best]

As Whpes said, no heat where pipes are & they will freeze after time, no matter you bury them in insulation.
An unheated building will turn into a fridge & hold the cold, then get colder each day the temperature stays well below 0.
I tell people that say heavier lagging will stop pipes freezing, that get a short pipe with water in it & very heavy insulated it, then put in freezer - has to freeze & split.
Peteheat is spot on about keeping the insulated pipes between the ceiling & the fibreglass.