1930s Semi Refurb - Part 2 of ... (Edition: Boiler/Water Tank Relocation)

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I go copper everywhere if planning to stay in a home for a longer time.

I installed my first home's heating and HW systems (except for final gas connection/test of my pipework and boiler install) and had no issues installing copper as it's not hard to fit/bend and not a single tapping sound or creak in operation. In my current house I got the professionals in for almost a month and requested copper and spent the next year removing floorboards in several rooms and separating tapping pipes or allowing for expansion on longer pipe runs. I am still happy with the choice, not so much their fitting!

I know push fit (which can even be copper now) is all the rage given how much faster/cheaper it is to install, but how well those sealing rings work decades down the line of heating and cooling and pressure change in heating is my concern.
 
Simon42 said:
I go copper everywhere if planning to stay in a home for a longer time.

I installed my first home's heating and HW systems (except for final gas connection/test of my pipework and boiler install) and had no issues installing copper as it's not hard to fit/bend and not a single tapping sound or creak in operation. In my current house I got the professionals in for almost a month and requested copper and spent the next year removing floorboards in several rooms and separating tapping pipes or allowing for expansion on longer pipe runs. I am still happy with the choice, not so much their fitting!

I know push fit (which can even be copper now) is all the rage given how much faster/cheaper it is to install, but how well those sealing rings work decades down the line of heating and cooling and pressure change in heating is my concern.
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I have no idea running copper and learning how to solder - my problem is how tf do you get a length of copper between joists that run the wrong way?
 
dLockers said:
I have no idea running copper and learning how to solder - my problem is how tf do you get a length of copper between joists that run the wrong way?
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For standard joists the usual approach is to notch the top (not suitable for I beams as the top/bottom plate cannot be cut). Metal web joists have huge spaces so usually anything fits but few of us of lucky enough to have these.

In my current home I've got 18 rads and two zone heating however there's not a huge amount of joist notching as you plan the pipe runs to run as much parallel to the joists as possible (downstairs is solid floor so we had to cut channels in that no matter what pipe we put in).

If budget/time restricted me I would accept plastic and potentially spend the saving elsewhere on other projects. I don't think plastic push fit is bad, just not as good long term.
 
Simon42 said:
For standard joists the usual approach is to notch the top (not suitable for I beams as the top/bottom plate cannot be cut). Metal web joists have huge spaces so usually anything fits but few of us of lucky enough to have these.

In my current home I've got 18 rads and two zone heating however there's not a huge amount of joist notching as you plan the pipe runs to run as much parallel to the joists as possible (downstairs is solid floor so we had to cut channels in that no matter what pipe we put in).

If budget/time restricted me I would accept plastic and potentially spend the saving elsewhere on other projects. I don't think plastic push fit is bad, just not as good long term.
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Thanks - for some reason I thought notching was "against the rules"! Can't remember where I got that from.

Any guidance on chasing the rad pipes into the wall as opposed to having them come out of the floor? Do you need to wrap them to avoid corrosion?
 
Fyi this is useful if you've not seen it before regarding notching. It relates to new builds but similar should apply. Structurally notching is worse than holes thru the centre (which can't be done with copper)

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I got my house all done in copper (for the majority at least) , but in Hindsight I suppose maybe could have gone plastic as long as it is well fitted.


To be honest if you've never done it before and have loads to do /it's accessible I'd get a plumber to do it. If not Id do it in hep2o push fit fittings, ensuring its been tied/clamped fairly regularly. I've done some small mods in hep2o and compression fittings and it's fairly "idiot proof" stuff
 
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dLockers said:
Thanks - for some reason I thought notching was "against the rules"! Can't remember where I got that from.

Any guidance on chasing the rad pipes into the wall as opposed to having them come out of the floor? Do you need to wrap them to avoid corrosion?
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The risk of corrosion in brick/block walls is less than in concrete floors but I still give them some protection. Denso tape is commonly suggested for wrapping copper pipes, it can be messy but is slim which is useful for walls. For use in concrete floors I always go a wrap like Denso or similar tape for protection and then plastic backed hessian or pipe lagging for insulation.

For both copper and plastic you can reduce down to 10mm for the final radiator fittings unless its a particularly large rad (and mix and match). This means smaller flexible pipes in the wall and for standard style rads close to the wall you can then use a single radiator exit plate centrally behind the rad with the two pipes going across to the fittings from there giving a very clean look. It all depends on the size and style of rad really and if you want the whole house to match.
 
Simon42 said:
The risk of corrosion in brick/block walls is less than in concrete floors but I still give them some protection. Denso tape is commonly suggested for wrapping copper pipes, it can be messy but is slim which is useful for walls. For use in concrete floors I always go a wrap like Denso or similar tape for protection and then plastic backed hessian or pipe lagging for insulation.

For both copper and plastic you can reduce down to 10mm for the final radiator fittings unless its a particularly large rad (and mix and match). This means smaller flexible pipes in the wall and for standard style rads close to the wall you can then use a single radiator exit plate centrally behind the rad with the two pipes going across to the fittings from there giving a very clean look. It all depends on the size and style of rad really and if you want the whole house to match.
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10mm microbore is easy for self installs as well if one doesn't want to use plastic. You can bend the stuff really easy with no need for any joins under floors etc and terminate straight into a pushfot valve connector. My home heating is all 10mm microbore, not my choice as it was already here but it works just fine.
 
Right chaps - my preferred guy has come back with this:

  • Supply and fit a new Vaillant system boiler with system filter and Kingspan unvented cylinder in loft space.
  • Remove old boiler, flue, hot water cylinder, cold water tanks in loft.
  • Run electrical supply into loft to power immersion heater and boiler power supply.
  • Supply and fit a Hive heating and hot water controller
  • Run a 22mm cold mains, gas supply, heating and hot water supply pipes into the loft space.
  • The new boiler will have a new flue terminate through the roof tiles, new zone valves, auto bypass valve, system filter for 10 year boiler warranty, hot water cylinder will have a scale reducer to help reduce limescale. Fitting of a plywood wall backing to mount the boiler and pipework to in loft space.
  • All water pipework in loft to be lagged, boiler condense, and cylinder safety discharge pipework will be terminated per regulations to a drain or low level externally.
  • Remove bank of hot, cold and heating pipes in boxing low level in bathroom below window and re route underfloor boards or high level in kitchen.
  • Connect to the existing heating system and radiators, replace 4x radiators as supplied by customer in bedroom 1, bedroom 2, dining room and hallway, other radiators to stay as existing.
  • Power flush heating system.
  • A gas safety certificate issued on completion and a building regulations compliance certificate issued via gas safe and Vaillant, the boiler will be registered with Vaillant for the manufacturer warranty.
  • The manufacturer’s warranty is upheld if the boiler is serviced yearly by a gas safe engineer
  • All rubbish will be cleared away from site.

  • Vaillant Ecotec system boiler 10 year warranty, hot water cylinder
  • and associated works

  • Total Cost for works
  • £ 8,300 Inc Vat
Now to be honest this seems like a proper "Rolls-Royce" solution in that the cylinder/boiler will be both out of sight/out of mind - it means I can do whatever I want downstairs (extension wise subject to the world not ending), and he'll swap the rads for me (minor benefit but buys me a weekend with my daughter).

I haven't yet received any quotes for the combi idea I had, but in the long term this £8,300 proposal seems solid?

Thoughts?
 
Plot twist - I've had the quote for a combi come through -- £3890 inc vat. That includes fiddling with my pipework to suit new downstairs rads as well...

This guy is a much more "brute force and ignorance" though, so excludes any power flushing etc...
 
dLockers said:
Plot twist - I've had the quote for a combi come through -- £3890 inc vat. That includes fiddling with my pipework to suit new downstairs rads as well...

This guy is a much more "brute force and ignorance" though, so excludes any power flushing etc...
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Aint hot water cylinders costly in terms of energy/gas used to keep it hot?

Also, how did you end up choosing the boiler? Is there a guide out there that helps a noob choose one based on needs/wants?
 
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dLockers said:
Plot twist - I've had the quote for a combi come through -- £3890 inc vat. That includes fiddling with my pipework to suit new downstairs rads as well...

This guy is a much more "brute force and ignorance" though, so excludes any power flushing etc...
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That sounds expensive!

I had one fitted a few years back and it cost £1600 all in.

Or have they really gone up that much in three years??
 
IvanDobskey said:
That sounds expensive!

I had one fitted a few years back and it cost £1600 all in.

Or have they really gone up that much in three years??
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It's an F&E setup at the moment so needs about a grands worth of conversion.

Anyway I've settled that I'm going to go for the 8.4k proper job in the loft with all new pipework.
 
dirtychinchilla said:
22 mm pipe is rather large
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22mm is important for best flow rates in most pipework (heating or HW) and especially the mains feed even if the external house cold supply is less than that at present as it reduces flow restriction and allow for a mains supply pipe upgrade down the line. Old homes may have half inch supplies, more modern 25mm MDPE generally.

In our case we upgraded to 32mm mains supply pipe to the house and ran 28mm copper internally (similar internal diameters) all the way to the HW cylinder and cold feed splits (goes down to 22 and 15 later on). We've got a similar 28/22/15 mix for CH.
 
200sols said:
Looks like a decent amount of work for the price that.
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Yeah it's from a bloke I trust as well. Local lad my age who works with his old man. He did my rad move in the last place - meticulous.

Edit: replace all pipework is limited to heating system itself, so existing rad circuit - but he will do a proper power flush and replace 5 of the rads that I supply.
 
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dirtychinchilla said:
I was thinking about your situation. Personally, I'd go with a combi. I'm still not convinced that instant hot water is a good enough benefit to having a cylinder. The disbenefit of having a cylinder is that you nee da higher DHW temperature. So I would go combi personally.

You have a great opportunity here to have a super efficient heating system, which is what people in the UK need right now. If I had that opportunity, I'd go all out. Oversized radiators, small pipework, low flow temperature, high delta T, good TRVs etc
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Does cylinder /conventional boilers use up more electricity /gas than a combi boiler?
 
Simon42 said:
For both copper and plastic you can reduce down to 10mm for the final radiator fittings unless its a particularly large rad (and mix and match). This means smaller flexible pipes in the wall and for standard style rads close to the wall you can then use a single radiator exit plate centrally behind the rad with the two pipes going across to the fittings from there giving a very clean look. It all depends on the size and style of rad really and if you want the whole house to match.
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I'm thinking 10mm in the walls is only suitable with stud walls? Chasing channels in single-skin block/brick walls deep enough to take this sounds like significant weakening, given how much larger this is than the usual electric cable you do that for.
 
jonneymendoza said:
Does cylinder /conventional boilers use up more electricity /gas than a combi boiler?
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In theory yes pretty much certain and in reality almost always
There are some mitigating factors that will bring a tank closer to a combi, repeated calls for hot water will see higher losses in repeatedly heating pipes to the taps with a combi, but if that taps closer to the combi than a tank that reverses back.

The benefits of a pressured tank (I would recommend this over an old system one) is that its mains pressure hot water and the flow will be higher. Its really a quality of life benefit not a financial one.
My megaflow lists around 2kwh a day loss but I forget at what temp as the label is behind the tank in the cupboard so I cannot easily see it. So around 20p a day at current gas prices.

There are a couple of financial ones now though.
Solar diverters sending spare electricity from generation into the hot water tank, assuming you have some spare when you generate
And linked to above, if your on solar and especially if you have an EV you are likely to have something like a Go tariff which means electricity (with 100% effectiveness) available for 5/7.5p a unit as opposed to using gas at less than 100% efficiency.
 
jonneymendoza said:
Aint hot water cylinders costly in terms of energy/gas used to keep it hot?

Also, how did you end up choosing the boiler? Is there a guide out there that helps a noob choose one based on needs/wants?
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It depends - I think in my old house on an unvented cylinder with modern boiler I was paying 80p a day for 2x heat ups of a tiny vented tank. I imagine my new boiler will be similar but for much more water (and potentially only needs to come on once).

I didn't get involved in sizing the boiler, it all seems a bit of a muchness at my end of the scale (like 400 quid difference across the range). It depends on number of rads primarily iirc.
 
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