Boxing in Vertical Pipes — Questions

paperclap

Hi all,

In the middle of boxing in some vertical central heating pipework. But before I box it in, I’ve a question.

Should I insulate the pipework before boxing in? Most say no, but hear me out. I was going to seal the gap between the living space and loft space, so no cold air could get to these pipes from the loft space to cause condensation or freezing. However, if that hole is sealed, there is no place for this heat to escape, as this boxing in will effectively act like a chimney.

I’m concerned, as we’ve recently had condensation on some of these pipes (in the living area, that were located near the loft space, going up).

Do I either insulate with Thermawrap so no condensation or freezing can occur, and leave the hole open to allow for any heat build-up to escape? Can’t lag the areas of pipe where the Talon clips are of course.

Or, leave the pipes uninsulated and seal that gap between the living space and loft space?

All of the above may sound ridiculous… but I really don’t want condensation on these pipes after I’ve boxed them in!

Thanks!

FreeBear

I'd insulate. The pipe wrap can be notched where the clips are, so you'll get 99% coverage. Seal the hole in the ceiling with something flexible (expanding foam ?).

I've insulated all my CH pipes where they run under floorboards and behind kitchen units - It keeps the heat in the pipes until they get to where it is needed.

BUFF

iirc you also need to leave access to the pipes for servicing so use screws rather than nails or consider something like https://www.talon.co.uk/products/pipe-cover-and-accessories

paperclap

FreeBear said:

I'd insulate. The pipe wrap can be notched where the clips are, so you'll get 99% coverage. Seal the hole in the ceiling with something flexible (expanding foam ?).

I've insulated all my CH pipes where they run under floorboards and behind kitchen units - It keeps the heat in the pipes until they get to where it is needed.

Think that’s probably best.

I don’t think it’s possible to notch Thermawrap insulation really… as it would just be too fiddly to fixate. Then again, the Talon clips are clipped in… so may not even need to insulate those tiny tiny gaps anyway. Insulate up to the clips, then there shouldn’t really be much copper to see 

If I fill that gap (the Thermawrap might plug it sufficiently anyway!), will that not trap the heat in the boxed structure?

FreeBear

When I've used pipe wrap, I've just notched it at the back to clear the bit of clip between the wall & pipe. Cable ties then hold everything in place.

You are overthinking the heat being retained in the boxing - It will leak out into the room - It won't get that hot inside the boxing (maybe 70°C).

paperclap

FreeBear said:

When I've used pipe wrap, I've just notched it at the back to clear the bit of clip between the wall & pipe. Cable ties then hold everything in place.

You are overthinking the heat being retained in the boxing - It will leak out into the room - It won't get that hot inside the boxing (maybe 70°C).

Thanks for the reassurance!

Perhaps you could help or suggest what to do with one more issue.

Back when I piped everything up, I popped a small length of 20mm plastic electric conduit over the pipe, thinking it would be good to stop any surrounding plaster touching the copper pipe.

Now of course with the Thermawrap, this isn’t necessary. As that would stop the plaster touching the pipework anyway.

However, I can’t actually remove the plastic conduit! Reckon I just leave it on there, say, somewhere on the pipework in the loft space and hope it doesn’t melt?

FreeBear

The plastic conduit won't melt - I've got a couple of pipes sleeved in the stuff to shield the copper from cement & plaster.

Even if the plastic does melt, it will only soften a little and won't leak out or burst in to flames.

paperclap

Covered the pipes in Thermawrap between the Talon clips, and up into the loft space. The Thermawrap ends up blocking the hole for the most part, so don't think I'll bother plugging the whole in any way.

The bottom fittings are an absolute pain in the back to try and insulate. Very tight, and awkward shapes. Do I bother insulating?