Unvented direct cylinders in 5 flats

[TimeServed]

Hi, I'm after some advice from you guys. Basically I have been drafted into a job as the client has been let down by the plumbers on site. The job consists of an old nursing home which is being refurbished into 5 flats. No heating, only hot and cold supplies to kitchen, bathroom and ensuite in each of the 5 flats. No baths, only 2 showers per flat. The original plumbers planned to have fortic cylinders and electric showers, but the client now wants mixer showers, which the original plumbers said would be ok as they can add pumps to the showers. Now this doesn't seem a great idea to me coming off fortics. Anyway I've had a look today and I feel that small, 90L or 120L direct unvented cylinders would be a much better option for each of the flats. I took a pressure reading which is showing 4.5 bar. My concern will be that the building has a 25mm poly incoming mains which then splits off to each flat in 15mm. I'm aware that I will need to feed each cylinder with 22mm directly from the mains but I'm just a bit worried about the 5 flats using numerous outlets at the same times. I have recently gained my unvented qualifications so I do not have great experience installing multiple cylinders with one incoming mains. Any suggestions and advice welcome, thanks.

 

[galaxy_plumbing]

you will need to go to 22mm

 

[TimeServed]

Hi Galaxy, yes I'm aware that I need to have a 22mm feed directly to the cylinders.

 

[on31ll]

is there room for accumulators ? or pump the mains ?

 

[TimeServed]

on31ll, there would be no suitable room for accumulators. Pumping the mains could be an option. As the original plumbers allowed for fortics and elec showers I imagine that the one incoming mains was suitable. After I mentioned the possibility of unvented cylinders to the client he was happy to have another incoming mains into the property but only if required, if the planned design with unvented cylinders is not producing enough pressure/flow to the outlets. This is where I don't really want to mess up, even though he has giving me a little insurance regarding another incoming mains......

 

[AWheating]

either seperate 25mm mains to each flat or a 50mm main to a manifold to 25/22mm main to each flat. Where are the water meters being fitted?

it al depends on what the client is willing to pay for, but either way 1 x 25mm main is not going to work with the orignal plan, each flat will require its own supply and meter.

 

[PriestyUK]

Dont forget about your discharges when siting your unvented cylinders mate And use combination valves to balance your hot and colds

 

[TimeServed]

Thanks for the helpful reply AWheating. The client will only ever be renting the flats and so there will be only one water meter. I like the idea of an upgraded 50mm mains with a manifold, this single 25mm mains is my concern. I'll be at the property all day tomorrow and will hopefully have more answers and questions.

 

[Destroyer2813]

I wouldnt even consider running 5 flats on 1 25mm main its bound to be your problem when the flow is poor, what about seperate electric meters they not having them either. How they gonna rent the flats then on a all bills included basis.

 

[TimeServed]

Agree on the 25mm mains Destroyer and this is why and where I'm looking for experienced advice. No he's not having separate electric meters either. I take it he's renting as an 'all bills included' but to fair that's his game and not mine. Thanks for the responses.

 

[lame plumber]

he'll regret not metering each flat, which as mentioned will need its own main feed to work. economy 7 or equivalent needed to keep costs down and 210 cyls to work properly on economy 7 for 2 bed flats, but check requirements yourself.

 

[jim fennessey]

i dont think any of this will meet building regs or water regs or electrical regulations has the guy got planning permission to convert this building into flats and if so the water undertaker will guide you , all i know when you make a material change of use to premises you must apply the latest regulations alround ie every flatted dwelling should have own electric supply and meter,and same with water,even if they are to be rented out i smell a rat somewhere with your client,dosent seem right

 

[helpsy]

If I recall in the MI with Gledhill you can supply in 15mm.. I know when I did the course it was 20 l per min and 22mm supply

 

[TimeServed]

Thanks for the replys guys. Regarding the regs I fully understand what your saying. The client has a large portfolio of properties in the area and has vast experience with this type of project. He likes to do things his way, so i'll be leaving that to him. I'm basically taking over and putting right what the last plumbers messed up. In regards to the water main, I have received more opinions from others and it seems like the 50mm incoming mains with a manifold split to each flat will be the best option. This will also be easy enough as the client owns a ground working company so no problems there. Thanks again for the advice.

 

[AWheating]

let us know how the job goes.

 

[TimeServed]

Will do, thanks.

 

[lame plumber]

Thanks for the replys guys. Regarding the regs I fully understand what your saying. The client has a large portfolio of properties in the area and has vast experience with this type of project. He likes to do things his way, so i'll be leaving that to him. I'm basically taking over and putting right what the last plumbers messed up. In regards to the water main, I have received more opinions from others and it seems like the 50mm incoming mains with a manifold split to each flat will be the best option. This will also be easy enough as the client owns a ground working company so no problems there. Thanks again for the advice.

its hard to mess up what is a pigs ear in the first place and the previous plumber may have been trying to work to an impossible budget, working for a landlord like yours will hurt you in the long term, been there and run away.

 

[TimeServed]

Thanks Lame, but the only advice I was after in this thread was regarding the mains water supply for the multiple unvented cylinders. I'm more than comfortable working with the client with our agreements and i'm also more than comfortable putting the last plumbers work correct and completing the job to a high standard. Thanks.

 

[lame plumber]

Thanks Lame, but the only advice I was after in this thread was regarding the mains water supply for the multiple unvented cylinders. I'm more than comfortable working with the client with our agreements and i'm also more than comfortable putting the last plumbers work correct and completing the job to a high standard. Thanks.

to get this done to the highest standard requires individual feeds to each flat, wait until 4 or 5 turn on their showers at 7am along with the rest of the world and the mains pressure is a bit low, seen it before and youll have a landlord kicking your bum for doing as he wanted.

 

[jim fennessey]

how can you correct the last plumbers work and leave a high standard when the building regs and water regs say about individual supplies and meters,you will be the one to get a heavy fine for contravening all the regs,and you are meant to supply a certificate saying all work meets regs to your client and send copy to local authority? also we are just trying to advise you to help out

 

[TimeServed]

Thank you Lame and Jim, advice taken on board.