How To Prevent Cold Water Pipes in the Attic From Freezing Up

[bobsy12]

I’ve got copper pipes in the attic feeding 2 showers. There is extra thick pipe insulation around every pipe and the insulation is checked on a regular basis. Last week the pipes froze. They have never frozen before and we’ve been in the house 7 years.
I know it’s been very cold but going forwards I’d like to prevent this from happening again if possible.
There used to be a cold water tank in the attic with additional pipes, but due to the installation of a combi boiler all these have now been removed.
The existing cold water pipes feeding the showers currently go through the ceiling and run parallel to the attic floor at about 2 feet high. I could lower these pipes and have the additional layer of attic insulation if needed.
I could add an isolator valve and shut off the cold water supply to the showers when its looks likely that the weather is getting cold.
Has anyone else got any additional suggestions please?

 

[JohnD]

if you can lower them to the floor or between the joists, and flop the loft insulation over them rather than underneath, they will be inside the heated and insulated part of the house, rather than in the unheated loft.

It is also possible to use electrical trace heating wires, against the pipes and inside the insulation, but you will not be able to tell if/when they are working.

Isolating the water supply will not prevent them freezing and bursting, you would have to drain the water out too. But it will greatly reduce the amount of water that escapes.

As you no longer have loft tanks it might be possible to reroute the pipes inside the house, perhaps under the floor.

 

[muggles]

What do you class as "extra thick" pipe insulation? 25mm wall thickness?

 

[bobsy12]

Yes, the pipe insulation is approx. 25mm thick.