On 12/11/2019 11:45, Tricky Dicky wrote:
One possible solution is to use insulated ducting:

https://www.i-sells.co.uk/product_in...oducts_id=2465

I believe it is mandatory on new installations under part L. The above company are quite good for having a comprehensive stock of various ducting and their helpline is particularly good at helping you get the right stuff, the bloke I spoke to was very good even though I was only spending approx. £60 with them. Alternatively if your duct is running along the top of the joists just feed your existing insulation over the top of it. I am not sure if it will entirely solve the condensation issue but will surely limit it.

Richard

I got this not in extractor fan ducting but in foul stack venting.
The pipe ran horizontal and exited under the eaves high up.

It sagged, watre bollected at a low point and te joint wasnt very
hood...and water ended up dripping down a wall below.

All my vents now slope down towards the outside


--
€œIdeas are inherently conservative. They yield not to the attack of
other ideas but to the massive onslaught of circumstance"

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