Pipework for downstairs radiators on new builds

[Mgrant]

Hi on some new new build houses I plan to first fix the up stairs radiators in 15mm copper coming up though the floor at the pipe centers for the radiator. i,e rad. length add 45mm per side and the correct distance from the finish wall. However I am debating how to feed the downstairs radiators, this pipe work is usual feed behind the dot and dab plaster. What do people find is the best way of doing this. Thanks for any advice.

 

[Chalked]

10mm plastic coated copper for me. I like to bring the pipe work out at the correct centres for the rad.
Hate the plastic plates behind the rads and feeding the valves like an extension lead.

 

[Mgrant]

do you use plastic to go through the joist in the ceiling void then go to plastic coated copper to drop the pipework down in the dot and dab wall?

 

[Chalked]

do you use plastic to go through the joist in the ceiling void then go to plastic coated copper to drop the pipework down in the dot and dab wall?

Yes. Short price of 15, then reduce down to 10mm. Never be tempted to tee off 10mm, it won't work.

 

[Mgrant]

Thanks and this causes no problem with the upstairs radiators being feed of 15mm all the way to the rad?

 

[ShaunCorbs]

Thanks and this causes no problem with the upstairs radiators being feed of 15mm all the way to the rad?

10mm for downstairs rads and 10mm for up else it just looks wrong/odd or even better 15mm for up and 15mm for down

 

[Chalked]

None at all. Run 15mm right up to the point that you are doing the drop. Make sure the rest is sized correctly too.

 

[Mgrant]

hard to do 15mm for downstairs though with hiding the pipework in dot and dab?

 

[Mgrant]

Chalked, do you pipe your first floor rads, up in 15mm coming up through the floor? If using 10mm for downstairs rads.

 

[ShaunCorbs]

Chalked, do you pipe your first floor rads, up in 15mm coming up through the floor? If using 10mm for downstairs rads.

no he means get as close a you can to the rad and use a 15-10 reducer and go from there

 

[Mgrant]

Ok, is there a way of first fixing the downstairs rads in 15mm (without loads of boxing ins) if the ground floor is a solid floor so can't do one drop then go under the floor to feed the rads.

 

[ShaunCorbs]

Ok, is there a way of first fixing the downstairs rads in 15mm (without loads of boxing ins) if the ground floor is a solid floor so can't do one drop then go under the floor to feed the rads.

yea but more work chase the pipes in and use either plastic or 15 mm coated copper

 

[Mgrant]

thought so 15mm un-chased in is too much to dot and dab over?

 

[missplumb]

we used to do 10mm downstairs and 8mm upstairs off manifolds on the landing, if your going to go behind dot and dab, do it before they put the boards on, its so much easier than chasing and chiselling the dabs then replastering!!

 

[ShaunCorbs]

we used to do 10mm downstairs and 8mm upstairs off manifolds on the landing, if your going to go behind dot and dab, do it before they put the boards on, its so much easier than chasing and chiselling the dabs then replastering!!

i like the word used to 😀 no one should be using 8mm these days for heating circuits/ runs to rads

 

[ShaunCorbs]

thought so 15mm un-chased in is too much to dot and dab over?

yes but depends how bad your dot and dabber is 😀

 

[stevetheplumber]

i like the word used to 😀 no one should be using 8mm these days for heating circuits/ runs to rads

theres no reason ytou couldnt use 8mm but its a lot of trouble using two sizes just do it all in 10mm of manifolds

 

[ShaunCorbs]

theres no reason ytou couldnt use 8mm but its a lot of trouble using two sizes just do it all in 10mm of manifolds

yea them horrible 8-10 trv adapters 😀

 

[Mgrant]

So if it's done all in 10mm copper how do you bring the pipes out to the radiators? Sorry for all the questions have usually just fed the first floor rads in 15 from below, as down stairs has had underfloor heating.

 

[ShaunCorbs]

So if it's done all in 10mm copper how do you bring the pipes out to the radiators? Sorry for all the questions have usually just fed the first floor rads in 15 from below, as down stairs has had underfloor heating.

if its upstairs then through the chip straight into valve, down stairs hole in plasterboard with elbow on 10mm pipe behind the plasterboard to get it as tight as possible, of-course all pressure tested before hand, but you never know with spreaders if you pipes are going to be where you left them