Frozen Shower Pipes in Attic

[bobsy12]

My Wife went to use the upstairs shower today and found it was not working - just buzzing. I tried the second upstairs shower and the same, so I'm guessing the pipes are frozen. They are gravity fed pipes which go into the attic and down to 2 showers. They are lagged and I've never had a problem with these pipes before. The showers were working fine a couple of days ago.

So I've no idea where to start. The roads are all snowed over, so I'm concerned that when the pipes start to defrost they will leak. I can't see which section of the pipe is frozen.
There are no isolating valves on the pipe that goes into the attic.

Please help!!

 

[JohnD]

Do you mean they are fed from a loft tank, and there are no valves on the outgoing pipes from the tank?

Tie up the float in the tank to stop it refilling. That alone will reduce the amount of water that can leak out to about 100 litres. If you are pretty confident there is no burst, you could leave it like that, and be prepared to turn on the bath taps to drain the tank quickly if a leak starts. This means you can continue using the kitchen sink taps until the problem is resolved.

If you are more cautious, run the bath tap now to drain the loft tank. Then the only water that can leak will be a bit remaining in the pipes. If you can get up into the loft with a hairdryer, you could then start trying to thaw out the pipes. The ice most likely started in an exposed part such as a valve or a badly-fitted join or elbow, or in a place where a cold draught enters, perhaps at the eaves.

It's helpful to change the loft insulation so it flops over the pipes, so they can receive heat escaping through the ceiling, and are insulated from the cold loft.

Make sure you know where the main stopcock is, and give it a trial turn. You might need it in a hurry. Stopcocks should not be wound open so far that they reach the end of their travel; open them then back off a quarter turn or so. This reduces the risk they will jam.

If your pipe lagging is not already the modern stiff plastic foam, invest in some, and the matching tape to hold joints and elbows closed. The foam can be cut with a serrated knife. Preferably use the "Bylaws" grade which is very thick. https://www.wickes.co.uk/search?text=lagging

Don't use the felt sleeving which is only suitable for preventing pipes rubbing and clicking.

 

[bobsy12]

Many thanks for your advice.
Sorry forgot to mention, there is no loft tank any more. The only pipes in the attic feed the showers. All the pipes have the modern thick insulation and where the pipes run along the attic floor they are also covered in loft insulation. We used to have a tank but that was removed when we changed to combi boiler. Some of the pipes run off the attic floor so they just have the modern thick insulation.
Advice further advice much appreciated.

 

[terryplumb]

You mentioned that the showers "buzzing". Are they instantaneous electric type ? If so unlikely to be fed from a tank ,rather off mains cold. If they are fed from tanks hot and cold ,they may have an electric pump. Either way isolate electrics to them to prevent damage .

 

[bobsy12]

Ok, thanks the showers are the instant type off mains cold. There are no electric pumps.

 

[JohnD]

They are gravity fed pipes which go into the attic and down to 2 showers.

no tank, so not gravity feed, then.

You'd better turn of the main stopcock until you have thawed them out. I suppose you can turn it on for short periods while you're awake and alert to a sudden leak and could turn it off at once.