Speedfit coldforms on 10mm pipe

[smallsteve]

I am replacing a standard rad with a towel rail in the en-suite and the existing pipes are 10mm Speedfit and not easy to change. The wall is standard breezeblock with plasterboard over the top. I am considering how best to re-align pipework for the new rail and would appreciate advice.

One easy option would be to use Speedfit coldforms (as per sttached picture), as it would mean not having to potentially cut new channels in the wall, which already has some cut into it. In this way the pipe would simply fit behind the pb. Thing is though, i’m not sure if this will restrict flow to the rail such that it doesn’t get hot enough? Also, will it increase likelihoood of blockage due to the narrowing of the pipe by the bend? Anyone used these on heating pipes, or should they only be used for non-CH?

If the bend in a bad idea, how deep do you cut into the wall for the pipe - i know that max is 1/3? How do you protect the pipe against the cut surface of brick? I guess you have to manually, carefully bend the pipe to come out of the wall horizontally? Not sure how much of a bend you should aim for?

Feeding a pipe up from the floor is not ideal because it is only a small rail and so will need to be fairly high on the wall i.e longish pipe run.

Any other options / considerations?

TIA

 

[ShaunCorbs]

Do they come out in the centre of the rad or just poke out the wall into the valve ?

 

[smallsteve]

Do they come out in the centre of the rad or just poke out the wall into the valve ?

Hi Shaun,
Currently the pipes come out of the wall and go straight into the valves on the old rad. But these existing pipes don’t line-up with the new rail and are too low down on the wall.

 

[ShaunCorbs]

Need to chase / you will find elbows behind the plasterboard

 

[smallsteve]

L

Need to chase / you will find elbows behind the plasterboard

The plasterboard is already off the walls and they have chased into the wall and then put mortar / cement over the top. There are no elbows though, unless they are underneath the mortar - see pic.
Are you suggesting that for 10 mm pipe there will always be a 90-deg elbow used, rather than just curl the pipe around a chased cut?

 

[ShaunCorbs]

Yep as the radius would be too great or they’ve chased a deep section out of the block

 

[smallsteve]

Yep as the radius would be too great or they’ve chased a deep section out of the block

I suspect they went deep, as i can see the curvature in the pipe as it enters the wall underneath; the floor is also up.
What about those coldforms, do they not do away with the need for extra fittings or deep chases?

 

[ShaunCorbs]

There ok but you still need to chase out around 2”

 

[smallsteve]

There ok but you still need to chase out around 2”

(Tile + addy = 13mm) + (PB = 13mm) + (gap behind PB = 10mm) = 36mm

So, would i be looking at channelling ~ 14mm just around the coldform joint? I’m guessing that the face of the cf joint could be flush with the face of the tile, as it will be covered by a clip-on plastic cover and so won’t be seen?

Are my concerns raised initially about using these CFs on 10mm CH pipe unfounded?

Which would be the preferred choice out of a CF joint, or elbow? Wasn’t sure about putting elbows in walls, but then again it’s not much different to having them buried under a tiled floor I guess!?

As regards protecting the pipe, would I just use hairfelt, 15 mm conduit or something else altogether? I don’t think originally they bothered with anything!

Apologies for all the questions and TIA.

 

[ShaunCorbs]

Yes 20mm deep or tbh I would want the form in the wall upto you

it’s fine tbh better than an insert won’t change the dia of the pipe

Ideally no joint in the wall / where you can’t get to but sometimes this is impossible

As it’s plastic it’s just expansion you could use some foam or felt lagging upto you

 

[smallsteve]

Yes 20mm deep or tbh I would want the form in the wall upto you

it’s fine tbh better than an insert won’t change the dia of the pipe

Ideally no joint in the wall / where you can’t get to but sometimes this is impossible

As it’s plastic it’s just expansion you could use some foam or felt lagging upto you

Ah, i hadn’t thought about the narrowing caused by inserts. That’s a very good point and makes me feel much better about using the Coldform joint.
Thanks again for your time and assistance.