Preventing freezing of over-ground outdoor pipe

FreeBear

Another_Level said: Happy digging!

Depending on the distance and accessibility, it might be worth hiring a mini/micro digger for the day. If there are any other heavy duty landscaping jobs to do, get it for a whole weekend for not a lot more.

Section62

Another_Level said:

If the water pipe is on the water companies mains pressure water supply burying it to the required depth would remove many risks including freezing.

Mains water pipe can be run in other ways closer to the surface although Advanced notification is required 

If the water pipe is not mains water, the water company is not interested   

The BiB needs the clarification that the regulations apply to water fittings at premises supplied by 'mains' water, not just those using or passing water at mains pressure.

https://www.legislation.gov.uk/uksi/1999/1148/regulation/2
"2.—(1) Subject to the following provisions of this regulation, these Regulations apply to any water fitting installed or used, or to be installed or used, in premises to which water is or is to be supplied by a water undertaker or water supply licensee."


So the water company should be interested in water pipes connected to (say) a storage tank in the loft supplied by the mains, but won't be interested in water pipes supplied by a private source (unless there is a risk of cross-connection)


In other words, if the original source of the water in the pipes the OP is talking about is from the 'mains' then the regulations do apply and the water company should be enforcing them. (but rarely do)


[Not disagreeing with you, just pointing out "mains water" in the BiB is ambiguous, and doesn't mean what some people might hope.]

Swasterix

andre_xs said:

Hi Everyone!
During Covid, we created a little home office in the shed. There's a toilet in there, so we put a water (15mm plastic pushfit) and waste pipe (40 mm with macerator pump). Because we needed it quick, we did it as a quick and dirty job, and the pipes are overground. I want to dig this a little bit in now, but there are some bits where I can't get the pipe underground (e.g. patio slabs, tree roots).

Last winter, the pipes actually froze 2-3 times for a few days. Luckily without any damage (are these speedfit pipes frost save?), but I don't want to take the risk...

So, I thought about the following for the (fast approaching!) winter

1. create a duct for everything which runs to the shed (warm water, cold water, waste pipe, electricity (armoured outdoor cable), ethernet)
2. Whenever possible, dig in this duct (not too deep, just 10-20cm or so). Probably just deep enough to simply cover it on top with a decking board or so.
3. Try to insulate the duct with left over styrofoam and proper pipe insulation.
4. However, I think the above won't be enough to prevent freezing in colder spells (luckily I'm in the south of England, so it rarely gets really cold), so I thought adding a heating element which lays with the other stuff in the duct. If frost is forecast, I would turn it on, otherwise it stays off (=fully manual control)

The duct needs to be very roughly 18m long.

The heating shouldn't cost too much, so I thought about the following options:
1. Plant warming cable (e.g. for greenhouses). 20m (6W/m), IP68, £45
2. Underfloor heating cable kit (just a loose cable, not fixed into any shape). 12m/150W (so 12.5W/m). £70 (but I would need two of those)
3. Probably very expensive: There seem to be snow-melting and self-regulating cables, e.g. for roofs and gutters (e.g. 'warmup').

I would think (1) is the optimal solution. It's not getting very cold here for long times, so that this cable should be warm enough. I also would think that the wattage is low enough that even if someone puts it on during the summer / forgets to put it off to pose a fire risk? The warmth/heat should always be able to dissipate well enough in the duct.

However, I don't know anything about this at all, so maybe I'm missing something and this solution is not good / dangerous, or there are better solutions available?

Any help greatly appreciated!

Not sure whether you have a sink in there (hoping you do since you’ve got a toilet…)? Do you drink the water….? The first thing that crossed my mind when I read this - Legionnaires.