Frozen pipe in loft

[regsmyth]

The cold water feed to the kitchen runs through the loft of my bungalow.

The first half of the run is above a poorly insulated ceiling and consequently doesn't have a problem. However on very cold nights (eg minus 10c) it can freeze somewhere along the second 10m section where I have properly insulated the ceiling with kingspan, despite it being insulated with the thick pipe lagging.
Does anyone have any suggestions how this can be resolved?
Is there some sort of "frost protection device" for this sort of problem?
I am considering re-laying the pipe under the ceiling, but it will be quite a job as it will have to pass through several walls.
I am also planning to insulate the ceiling in the hallway properly, so the problem is likely to get worse.
Any helpful advice welcome.

 

[gas112]

do a google search on trace heating

 

[JohnD]

if you had insulated the loft with mineral wool, you could have flopped it over the pipes, then they would be on the warm (house) side not the cold (roof) side.

if it keeps freezing, it will sooner or later burst.

 

[Charnwood]

Never insulate UNDER pipes and tanks in loft spaces.