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

 

[Mgrant]

is coming up though the chipboard in 10mm not a bad idea as microbore can be knocked and squashed easily? For down stairs are you saying drop the pipes then run them horizontal above skirting board height?

 

[ShaunCorbs]

is coming up though the chipboard in 10mm not a bad idea as microbore can be knocked and squashed easily? For down stairs are you saying drop the pipes then run them horizontal above skirting board height?

yea and no, thats how most people i seen do it thats why i like to do everything in 15mm +. and depends on what the builder wants see a few just drop it center of rad straight down and then others bring it down in a corner and either behind the skirting or higher than it

 

[AWheating]

Double post, soz

 

[AWheating]

There are several ways and each has its own benefits. The neatest and quickest is 10mm plastic into 1st fix triangles. The best would prob be 15mm copper coated or wrapped fitted inline with the valves, and alternative would be 10mm copper and chrome pushfit rad valve elbows, that would be nester than 15mm. As for upstairs go up the dab and out so when finished they look the same as downstairs.

You will get 15mm pipe behind most dabbed boards.

If you use 10mm as a rule if thumb upsize as soon as possible, but keeps each flow and return under 5m if it's plastic pipe.

 

[Mgrant]

Thanks for the replies. Sure I have seen it done dropping 15mm pipes down in plastic in the corner of the wall were the rad is to be then the pipes are swept/ bend so they run just above the skirting board. ( to avoid nails). Then elbowed out in copper. The pushfit elbow is just chased in to the wall. Does his sound right?/ acceptable?

 

[AWheating]

Not a good idea to fit a plastic elbow or any plastic fitting in the dab void, if the plasterer incases the fitting and pipe next to it in board adhesive it's grab ring can be stopped from biting down on the pipe correctly. Seen it on a job the other week, 5 grands worth of damage to a new property.

You also need to be able to detect the pipe with a wall scanner, you can use trace tape of course but it's just as cheap and safer to drop in copper inline with the valve or in the middle of the rad, either of these positions is easy for the owner to remember the position of the pipe work.

 

[JCSPLUMBING]

The way I've done it is tee off the 15mm at the wall and run up behind the dot dab in 10mm and elbow out with 10mm, 90 degree copper tails into the rad. IMO upstairs should look like downstairs.
Make sure you check the fittings before you put the copper tails in as they can get caked in dab mix. I think when it's done like this it looks neat and tidy

 

[Mgrant]

So I am struggling to find a viable option for feeding the downstairs radiators in 15mm?

 

[ShaunCorbs]

So I am struggling to find a viable option for feeding the downstairs radiators in 15mm?

no easy do it right the first time and chase them in prob take 2-3 hours to chase all of down stairs rads in with multiple drops

 

[Mgrant]

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

How would you recommend bringing the pipes out for the rad then if using this method and using plastic

 

[ShaunCorbs]

How would you recommend bringing the pipes out for the rad then if using this method and using plastic

in coated copper and you know you centers of valves bring them out about 2 - 3 inches below and once dry lined and plastered soldered elbow and short piece done

 

[ShaunCorbs]

whats your trade james ?

 

[AWheating]

Pegler Push-fit Elbow 10mm | Chrome Compression | NoLinkingToThis

get your pipes level and fit these.

 

[gassafe]

Pegler Push-fit Elbow 10mm | Chrome Compression | NoLinkingToThis

get your pipes level and fit these.

Not much room for error fitting these if your pipe is coming straight from the wall... I always think new builds look smart when they bring the plastic out behind the Center of the rad & then flex into the valve with one of these fittings!

 

[AWheating]

if you know your valve dimensions it should be easy and there will be alittle movement unless the plasterer dabs the end.

the new build way does look good, just have to take into account that it can be dangerous on very small rads as kids can knock the rads off the brackets very easy.