Underground radiator pipes

[seasickstevie]

Want to run flow and return under garden to shed/log cabin about 14m from house.

Obviously need good quality Armourflex or similar. Is there a way to run both pipes in a single underground duct? Or owing to the o/s dia of the insulation, will I need two separate ducts? Not looking to over-complicate the project.

And is there a recognised depth I need to dig?

 

[RF Lighting]

I'll start off by saying I'm not a plumber, but I did this at my house. I installed a 110mm duct from the house to the garage using soil pipe components.

I buried it 750mm deep which is the standard depth for water pipes to prevent freezing.

I have learnt from my bad experience. I tapped the garage off the nearest flow and return pipes in the house, but unfortunately one very cold winter night one of the pipes in the garage froze and burst as the house was still warm so the heating was not running, and caused massive flooding as my heating has a header tank which kept refilling all night.

To do the job properly you need to supply your shed on it's own zone with independent controls so in the depths of winter a frost stat will prevent freezing in the shed without turning the house into an oven.

Also make sure you seal the ends of your duct properly. I stuffed mine with rockwool, but mice chomped a hole through that and used the duct as a handy route between the house and the garage. I have now shoved the rockwool further in the duct and covered it with an inch of sand and cement mortar which has solved the problem, and can easily be broken out if I need to access it again.

 

[U6]

http://www.uponor.co.uk/en-gb/solutions/local-heat-distribution.aspx

The best way, but think you'll cry at the price.

 

[Norcon]

Polypipes pre insul 32mm x 15mtr Htg Twin Pipe Coil is £650 quid per roll.

 

[Agile]

It is sometimes worth considering separating the supply to the shed using a plate heat exchanger and a pump.

Then the shed can be turned on/off by powering the pump.

But the separate shed circuit can be heavily dosed with antifreeze to avoid freezing problems without needing to waste heating all winter.

Tony