Really? Pipe clips

molerat

I managed to screw clips under the joists in an extension, the joist was only about 8" from the ground.  All insulated with pipe insulation as were any original pipes that were accessible during the work

Fen1

I've been going round and round in circles trying to find the pertinent Building Regs ( Wales ). I've found the regulations for new builds, but not refurbishment of older buildings.
I would be grateful if I could be pointed in the right direction.

Risteard

Section62 said:

Mistral001 said:

The problem is actually getting room to swing a hammer or get a screwdriver in the floor void to fix the clips to the underside of the joists.

I find thin galv. steel straps are very useful to fix things where there does not seem to be a purpose made fixing available.  In this situation you would cut off a length of the strap and twist each end through 90 degrees and bend the middle of the length of strap under the pipe and simply nail each end to the side of the joists.  See link below for strap:

https://www.screwfix.com/p/sabrefix-builders-band-galvanised-dx275-9-6m-x-20mm/38619

The strap can be easily twisted with two pliers or pliers and a vice and cut with tin snips as it is only about 1mm thick.

Galvanised steel shouldn't be used in direct contact with copper or brass though.

Indeed I was going to make a point about dissimilar metals (although there is a PVC coated variant which is the only type of this I use), although my remarks about padding it would mitigate this anyway.

FreeBear

Fen1 said:

I've been going round and round in circles trying to find the pertinent Building Regs ( Wales ). I've found the regulations for new builds, but not refurbishment of older buildings.
I would be grateful if I could be pointed in the right direction.

Building Regulations, Part L is the starting point. But there are also a bunch of other documents such as British Standards (which you have to pay for to get access) that cover the finer details. In a nutshell, if modifying an existing heating system, the aim is to make sure the changes do not make things worse. So if pipes are uninsulated, no mandatory requirement to insulate. Best practice says it is a good idea, and to use the thickest insulation that is practical - Part L does say that heat loss from pipes should be minimised (page 54).

Fen1

Thank you to everyone. I'm having my system checked, just to make sure there's nothing ( more)  iffy.

ThisIsWeird

You don't need reference to Building Regs - this is just awful practice. 
Is that underfloor void ventilated to the outside? Even if not, they must run a significant risk of freezing, not to mention the staggering heat loss from them. 
And that 'sling' is not mouse-proof.

Fen, do you wish to DIY this? Is will, pretty much, be as easy a DIY task as could be.
See the foam lagging that Grumb(?) linked to, or ideally thicker stuff while you're at it? It just needs a sharp craft knife run down its length, where it's already partly-sliced for this reason. This will allow you to prise it open, and slip it over the pipes. Is that within your remit? If so, I'll take you through the whole process. If not, get a plumber or handypeep in - this doesn't require plumbing skills as such.

Fen1

ThisIsWeird: thank you for your kind offer of help. You have no idea how much this kindness means.

I am sure that between us, OH and I can figure out the lagging. It can't be more difficult than making a sausage roll. What's the best method for going around joints and corners? And when I get to joists?

ThisIsWeird

You will need:

Craft knife with long blade: https://www.screwfix.com/p/forge-steel-snap-off-knife-set-2-pieces/349xg

Insulation - either 15 or 22mm to suit pipe: https://www.screwfix.com/p/economy-pipe-insulation-15mm-x-13mm-x-1m/72357

Foil tape  -not essential, but recommended: https://www.screwfix.com/p/diall-aluminium-foil-tape-silver-45m-x-75mm/4415v

Strapping - either will do: https://www.screwfix.com/p/sabrefix-builders-band-galvanised-dx275-9-6m-x-20mm/38619 or https://www.screwfix.com/p/ced-all-round-band-12mm-x-10m/18298

Screws or nails to secure the strap to the side of the joist.

The insulation just gets slipped on to the pipes. You'll find the insulation lengths are part-sliced along their length - carefully go through to the centre using the craft knife blade set to around 15mm protrusion, and jobbie jobbed. Gently open the gap, and slip it on.

At corners, pre-cut the pipe at 45o using the extended blade as a slicer. Slip it on, and push it along the pipe until it half covers the bend. Repeat from the opposite direction - the two mitres should butt reasonably well.

When done, cover all corner joints with the Ali tape. Also worth running a strip along the insulation length to ensure the sliced cuts are kept closed. It doesn't matter how many pieces of insulation you use - how many joints there are. Just try and get them reasonably tight, and then tape them.

NB: Do one joist at a time. Build up something from the concrete base to support the pipes whilst you remove the slings - a pile of books, bricks, whatevs - and release and lower the pipe just enough to allow the lagging to slip on - so around 15mm drop from the bottom of the joist.

Looking at your pic again:

I have no idea what your plumber used there. On my phone, I'd assumed it was like a boot lace! Here, it looks shiny, so perhaps a rubber band of some sort? I simply have no idea if it is suitable, because I don't know what it is. It might well be ok, I just don't know. If it's 'rubber', then I'd fear it hardening or perishing over time and breaking away. If neoprene, then it may well last ok, but hardly mouse-proof. Do you have any idea what it is?

Anyhoo, assuming you are not going to reuse it - but that's your call - the alternative is the strapping. The idea will be to form a coat-hanger shape, and the pipes will run side-by-side. Use a piece of string to work out the length required - start at the rough mid-point of the joist, down under one pipe, continue under the other, and back up. Transfer to the strapping. I imagine the strap will snap with repeated bending. Use pliers if it's stiff, or just do it by hand if not (but watch for sharp edges), to form the shape, and then have both upper ends coming together, with the top holes overlapping. Slip it under the pipes, slide it along until it's against the joist, pull it upwards until the insulation is snugly against the joist bottom, and just hammer a short nail - a 2"-er will do - through a suitable hole. Slope the nail downwards so's it acts like a slight hook and the strap cannot slip off. Or, use a screw - ditto.

Move on to the next joist.

That sound ok?!

FreeBear

ThisIsWeird said: I have no idea what your plumber used there. On my phone, I'd assumed it was like a boot lace! Here, it looks shiny, so perhaps a rubber band of some sort?

Cable tie - I've got a bunch of them holding pipe insulation in place on my CH pipes.

Fen1

Thank you for the detailed info. It is genuinely appreciated.

It's a bog standard cable tie. If it were my ex-landlord it would be sludged on with mastic.