New build first fix help needed

[David Lowth]

Have been sadly let down by a plumber and doing the first fix for a new build. I have questions regarding the correct procedure for chasing in pipework behind what will be dot and dabbed..

Its 3 bed bungalow with 9 radiators in total.

I was planning on running lagged plastic22mm flow / returns in the roof space to and tee off 15s for each radiator. Some of which are underneath windows.

1. How deep do you usually chase when its being dot and dabbed? And do you also just take a notch out of the wall plate?

2. Would you chase one larger channel and run both pipes in the same place?
Does the plastic need to be insulated or ducted in some way so it could potentially be removed at a later date?

3. The rads will be attached to chrome.. would compression fittings with liquid ptfe be ok to use to connect the chrome to plastic? But obvioulsy this wont be able to be removed at a later date without pulling the wall apart.

4. How would you chase it in? Straight line down the wall with an elbow at rad pipe height?

Finally anything else ive overlooked / missing? How would you usually approach this job?

Thanks in advance for any help

 

[ShaunCorbs]

How you going from chrome pipe to plastic ?

 

[David Lowth]

Was thinking Brass Compression fittings with liquid ptfe.. i havent had anything leak with that stuff i think its great

Or does it have to be copper and soldered behind dot and dabbed plasterboard?

 

[Riley]

You’re going to have joints galore in the wall from what you’re saying

 

[David Lowth]

Yes at least two per rad at a minimum which is why im trying to get advice from a professional on how they install in this situation? Or if this is acceptable?

Looking at the building regs document G i havent been able to find a clear answer yet.. but it is a long document..

 

[Scott_D]

Chrime straight into the rad valves?
I would avoid compression in the wall

 

[ShaunCorbs]

Nope on compression in the wall

 

[David Lowth]

Can you use 10mm plastic pipes into a junction box directly behind the rads?

Just seen someone suggest this. Then there would be no joints in the wall?

 

[ShaunCorbs]

Manthorpe Radiator Pipe Guide & Seal | City Plumbing Supplies

 

[Riley]

Yes you can but make sure everything is sized/designed properly. Microbore can be problematic

 

[Scott_D]

If it’s dot and dab do you need to chase the wall?
Put a pattress behind rads

 

[David Lowth]

Manthorpe Radiator Pipe Guide & Seal | City Plumbing Supplies

That looks great, thanks very much. And then just go plastic all the way into the rad valves?

I wanted to conceal as much pipe work as possible and not have any plastic on show..

Yea i get what you mean on 10mm.. i would rather use 15..

Can you get these for 15mm pipe?

Sorry if i sound like a complete moron. Im not the whole time i swear. I just had to look up what a pattress was..

So if the pipes terminate in a patress behind the rads, the dot and dab board just goes to the depth of the patress?

 

[ShaunCorbs]

No they don’t do them in 15mm

 

[Rob Foster]

Maybe you can explain the contract you established with your contractor. Show us the detail then we can see what has been achieved and crucially what has not. Have you paid any lolly up front or any part payments and if so for which part of this work which has been completed and to your satisfaction etc
regards Rob Foster aka
centralheatking

 

[David Lowth]

The issues with the contractor is he was given £3500 in october by my business partner.. unfortunately without my signoff as i was out of the country.

My business partner was told by the builders he needed to get the plumber on site asap to sort the first fix stuff before the floor went down. The builder went ahead and did this himself in the end. The plumber was supposed to have the first fix in place by three weeks ago. Then he failed to answer calls / return messages since then, would eventually get a response after days of voicemails. When he was supposed to be coming.. oh he had a hospital appointment, or a problem with his phone.. etc

Basically he has very terrible communication skills and only after saying hes taking the Sod today, and at my wits end i said just give us the deposit back ive had enough, he has said to my business partner he recieved a aggressive message from me and acting all confused and innocent, saying he could do the first fix by 28th march..

Thats too long, and holding everything up.. so asked for the deposit back.. which is likely to be a whole another problem..

 

[David Lowth]

He fitted a stopcock and a end cap tje rosd side, half a days work if that but said give us the deposit minus one days work for doing those tiny Jobs.

 

[David Lowth]

Anyway back to the job..

Can i use 10mm plastic for just the rads under the windows / dot and dab and 15mm in studwork? Or do you need to use the same type of pipe everywhere?

Some of the rads are 10,000 btu's..

 

[Riley]

10000 btu = nearly 3kw
10mm will carry approx 2.5 kw

 

[David Lowth]

Ok so 15mm on those two rad that are approx 10,000 btus and 10mm elsewhere ok?

If i balance the system and throttle down the 15mm rads slightly can you see this working effectively?

 

[Riley]

It needs proper design is it all new going in?

 

[Sharp Point]

Find another plumber

 

[David Lowth]

Yes all new going in.

Or just stick to the original plan of 22s and 15s but chase the walls and do plastic to chrome compression fittings coming out to join the rads.

I dont want to see any plastic in the rooms only chrome

 

[David Lowth]

This was my original plan

 

[ShaunCorbs]

I wouldn’t pipe the whole cold system in 15mm plastic

Would say a min of 22mm plastic

TBH your looking at 2-3 days to first fix that (a decent heating engy )

 

[Riley]

But that way you are back to having fittings the wall which you don’t want

 

[ShaunCorbs]

The only way I can see it working is to put a backplate elbow in the wall and get the boarders to put it flush to the front and use a chrome male iron

Or soldered fitting

 

[David Lowth]

Ok, ill swap for 22 cold going to the two bathrooms.

Ive pretty much got the next two weeks. Just want to make sure its done correctly before starting.

If i can find some 8000s btu rads will that take 10mm pipe so i can do it all in 22 and 10?

The room requirement is 15,500 btus the only reason we picked two 10,000s was because they were a good price for what they were and matched the other rads.

Is the other alternative to do 15mm copper and solder in the walls and give up on the idea of only chrome showing

 

[David Lowth]

The only way I can see it working is to put a backplate elbow in the wall and get the boarders to put it flush to the front and use a chrome male iron

Or soldered fitting

Thats great, thanks for your advice

 

[ShaunCorbs]

What boiler ?

 

[Scott_D]

2 heating zones?

 

[David Lowth]

No boiler yet, wss going to be a Worcester or glo worm combi but changer of gas engineer now so have none at the moment.

2 heating zones? I dont understand. The larger room at the back has a vaulted ceiling but just has 2 rads in it.. sorry only one on this plan, but needs a second one added as 15,500 btu room

 

[Scott_D]

A new build should have 2 heating zones

 

[Riley]

If I were you I would seriously be looking to get another engineer in to do this properly

 

[Murdoch]

Gobsmacked ..... diy on parts that can’t easily be upgraded or replaced without major surgery on the property ......

 

[MOSSEP]

You could use 10mm copper micro bore in the wall rather than plastic, that way you can have soldered joints in the wall rather than compression / push fit.

 

[David Lowth]

A new build should have 2 heating zones

Thanks for the information. This is exactly why im on here

 

[David Lowth]

I see..

I will be getting another gas engineer to install the boiler etc, but in the mean time i can chase out walls and get the first fix in place so the walls can be dot and dabbed and its not holding everything up for months

 

[Riley]

As we’ve said though. Good engineer will have that done in under a week

 

[David Lowth]

Im actively looking for one.. but just cant have weeks of downtime waiting for their schedule to be free..

Im real annoyed with the current one going awol, but it is what it is and you live and you learn i guess

Unless you know of any.. or fancy a trip to ringwood yourself haha

 

[David Lowth]

Yes, where are you based?

 

[king of pipes]

This is how I do it no joins in the wall and can be dot and dabbed over . Cheers kop

 

[Riley]

Is that 10mm kop

 

[Tim S]

22mm on H&C's as far as you can. 22mm loop with 15mm drops to rads in copper. If it's all being dot and dabbed then drops can be hessian wrapped and clipped to block/brick behind boards. If you want chrome only on show file off enough chrome plate to solder it into the fitting. Cap it all and pressure test..Happy days🙂

 

[king of pipes]

Yes mate 10mm I have done it with 15mm from a loft void as below , but the first post was a refurb on two flats above a shop the walls were dot and dabbed over with insulated plaster board then skimmed there are no joins other than the manifold in the hallway cupboard just made sense as the floor voids were insulated with rockwool the boards put back , 10mm ply laid on top then a plank type vinyl flooring laid. Kop

 

[king of pipes]

This is how I do it no joins in the wall and can be dot and dabbed over . Cheers kop

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Would you care to explain your disagreement x David. Regards kop

 

[David Lowth]

Hey Kop, sorry mate, my fat fingers! Didnt mean to press that!

I was gonna write i totally get why you are the king of pipes! Very tidy work. Great stuff.

So after much consideration i think im going bite the bullet and chase and solder 15mm copper to chrome in the walls and pressure test before dot and dab.. although really like the look of that 10mm work..

I have a final question regarding zoning..

The bungalow is 110m2 but believe it may still need zoning.
The living space is just 3 rads, the rest in bedrooms or bathrooms.
Am i right in thinking i can tee off the 22 flow from the boiler to feed these 3 rads and just tee the return back into the return for the bedroom / bathroom rads?

Can Etrv valves be used as a zoning alternative? Are they building regs compliant, and essentially plumb in up as originally planned above. One flow and return feeding all rads?

 

[king of pipes]

Each to their own mate either way will work think I would use the drayton wiser system to zone it up they are building regs compliant cheers kop

 

[Nick Cox]

This is how I do it no joins in the wall and can be dot and dabbed over . Cheers kop

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Any particular reason the pipes couldn't come out from floor straight in to valves on the first picture

 

[king of pipes]

Yes mate the 10mm collapses and kinks .

 

[Nick Cox]

This is how I do it no joins in the wall and can be dot and dabbed over . Cheers kop

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Any particular reason the pipes couldn't come out from floor straight in to valves on the first picture

Yes mate the 10mm collapses and kinks .

i mean straight up from the floor in 15mm copper seems pointless putting them in the wall when you don’t have to or am I missing something

 

[ShaunCorbs]

Any particular reason the pipes couldn't come out from floor straight in to valves on the first picture

i mean straight up from the floor in 15mm copper seems pointless putting them in the wall when you don’t have to or am I missing something

guess customer didnt want to see the pipes

 

[Sharp Point]

Yes mate 10mm I have done it with 15mm from a loft void as below , but the first post was a refurb on two flats above a shop the walls were dot and dabbed over with insulated plaster board then skimmed there are no joins other than the manifold in the hallway cupboard just made sense as the floor voids were insulated with rockwool the boards put back , 10mm ply laid on top then a plank type vinyl flooring laid. Kop

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Nice neat work KOP, did you have sore neck from crouching and bending doing that?😱

 

[king of pipes]

Nice neat work KOP, did you have sore neck from crouching and bending doing that?😱

I survived bud not a big fan of plastic I will only use hep2o , as I said before with all the layers of floor materials and the walls being insulated I though that was best joins in the pipework were kept to a minimum and pipework was all hidden away . Kop

 

[Toby emery]

Take 15mm in the ceiling then use 2 x 15mm elbows with 10mm reducers above where the radiator is, then take the 10mm to the rad positions using a junction box to hold them in place. No fittings in the wall, make sure you nail clip the 10mm to wall with hair felt behind the 10mm for protection against the block work.

It works perfectly, been doing it for years and never had problems with flow rate.

Also it can be 1 zone as under 150m2. Part L 2014 got rid of that rule. Over 150m2 must be zoned.

 

[Riley]

All new build must be zoned

 

[Toby emery]

No, not since April 2014.

 

[ShaunCorbs]

No, not since April 2014.

Yes they do also in Wales sprinkler system must be fitted

 

[Aire]

No, not since April 2014.

That depends on house size and it doesn't say zones aren't required, it's says trvs at a minimum are deemed acceptable for zoning.

 

[Toby emery]

Yes if it’s over 150m2 it’ll need to be zoned and controlled by two different room stats linked to 2 port valves.

Well yes Trv’s are a must anyway, but being 110m2 it doesn’t need to be zoned via 2 port valves which is what people are implying by saying all new builds must be zoned.

 

[Aire]

Yes if it’s over 150m2 it’ll need to be zoned and controlled by two different room stats linked to 2 port valves.

Well yes Trv’s are a must anyway, but being 110m2 it doesn’t need to be zoned via 2 port valves which is what people are implying by saying all new builds must be zoned.

Yes so if your below 150m2 then trvs only are fine. That's the way I understand the regs anyway.

 

[Knappers]

I like pipe-in-pipe down the walls (and my Hilti wall chaser), does anyone else do that?

 

[Ryooo]

In regards to new builds requiring zoning I'm working on a Cala development with a minimum of 5 bed house and not one house type is zoned. Where as the site i was on before was 1/2 bed social housing and was zoned. Zone 1 was living room, kitchen, bathroom & hall. Zone 2 bedroom. Seemed pointless to me at the time.

 

[Aire]

In regards to new builds requiring zoning I'm working on a Cala development with a minimum of 5 bed house and not one house type is zoned. Where as the site i was on before was 1/2 bed social housing and was zoned. Zone 1 was living room, kitchen, bathroom & hall. Zone 2 bedroom. Seemed pointless to me at the time.

Has any house been finished/signed off yet? I'd bring it to the developers attention, remember that if your installing the systems, it's up to you to make sure they comply with the latest requirements.

 

[Ryooo]

Has any house been finished/signed off yet? I'd bring it to the developers attention, remember that if your installing the systems, it's up to you to make sure they comply with the latest requirements.

Yeah mate, there a into the 3rd phase with other 100 houses signed and handed over. The system is ASHP with hyprid boiler with an unvented indirect cylinder. I've not asked the agent yet but i think it's more to do with SEDBUK rating witch CH zoning obvisouly improbe as does ASHP. I'll find out more. I'm in Scotland also which might make a difference.

 

[OffshoreGas]

Burying pipes in a wall is expensive in both the short and long term.

Short term you haven’t got space to properly insulate them meaning a fair portion of your heat will be lost into walls/brickwork.

Long term you’re going to have to rip the room apart if ever you need access.

I dug about 50m of heating pipe out of the wall in our last house and ran properly insulated under the floor. Saved us about 20% on heating bills.

If it were my forever home I’d be avoiding plastic pipe if at all possible.

 

[Coby kenny AGUILAR]

Have been sadly let down by a plumber and doing the first fix for a new build. I have questions regarding the correct procedure for chasing in pipework behind what will be dot and dabbed..

Its 3 bed bungalow with 9 radiators in total.

I was planning on running lagged plastic22mm flow / returns in the roof space to and tee off 15s for each radiator. Some of which are underneath windows.

1. How deep do you usually chase when its being dot and dabbed? And do you also just take a notch out of the wall plate?

2. Would you chase one larger channel and run both pipes in the same place?
Does the plastic need to be insulated or ducted in some way so it could potentially be removed at a later date?

3. The rads will be attached to chrome.. would compression fittings with liquid ptfe be ok to use to connect the chrome to plastic? But obvioulsy this wont be able to be removed at a later date without pulling the wall apart.

4. How would you chase it in? Straight line down the wall with an elbow at rad pipe height?

Finally anything else ive overlooked / missing? How would you usually approach this job?

Thanks in advance for any help

1. Speak to the boarder usually around 15mm cavity, I wouldn't cut through any wall plates joist hangers ect.. Take the most direct route, keeping joints to a minimum

2. You can insulate pipes in a wall chase but there might not be any meat left on the block, example a 22mm pipe with 13mm lagging with an extra 5 mm to cover over the pipe would be a 40mm deep chase, in ceiling voids I insulate if it's being chase in the wall I don't, ducting is a good idea and is great in a concrete floor wouldn't use it in walls unless it was a data cable for a shower that has a processor

3. I prefer to solder on chrome, file the chrome off make sure it's very clean and solder an elbow onto it with clean copper, and push the copper into a couplin, that's the only time I put an extra joint in the wall

4. Find the most direct route, but keep away from where people hang pictures, where door hinges are (I had a chippy put a 4 inch screw!! through a heating pipe), you're normally OK though) avoid where the skirting will go.

I use hep20 and test 1.5x working pressure for 45mins. 10 bar for 45mins where pressure is not know yet (new water main ect..) waivin suggest 18 bar with no appliances connect but I have yet to try this for good reason lol I trust there push fit caps but not that much