run pipes above existing bathroom

[shardy]

Hi all,
we are having a bathroom installed in a new loft conversion. We were told during the initial survey that the water supply would be run up from the existing bathroom to the new bathroom above it.
The plumber didn't want to do that as it would mean disturbing the tiles. It was only 2 or 3 tiles that needed removing to get at the central heating pipes. The hot and cold were in a bathroom cupboard that was easy to remove.
So he took a feed from the pipes in the corner of the 1st floor back bedroom above the boiler in the kitchen, ran under the floor in the bedroom to a fitted cupboard, then up the inside of the fitted cupboard into the loft.
It was an easier and quicker way for him to get the water and central heating pipes into the loft. But that means the pipes now run diagonally under the middle of the floor of the new loft bedroom. I wondered if that is a good idea? I would've preferred the pipes to run from bathroom to bathroom or does it not matter? The water pipes have always been around the edge of a room wherever I've lived.
I've attached a crude diagram of the position of pipes in loft.
Also should the new shower, sink and toilet all have a stop valve on them?

many thanks in advance

 

[PrenticeBoyofDerry]

There is nothing wrong using the alternative method, providing you are happy with the install? Quicker/faster should save on labour costs and remedial work to tiled area.
I would always recommend fittings service valves to both hot and cold water pipes to appliance taps/valves. I do this on each occasion I fit new and often when undertaking remedial work when none exist.

 

[dilalio]

Bit late now but if it was your preference to have it the other way, you could have insisted! And maybe done the prep and make good for him!
Aside from that, the end result will be no different, I.e: it'll work just as well!

 

[shardy]

Thanks for your replies folks. If it works just as well and is less work for the plumber and myself, that sounds good to me. I suppose I was concerned if a valve ever leaked it and ran along the pipe it could drip on to the lights below. But that is unlikely and if everything is earthed I think that's fine. I'm wondering where he can put the service valve to the shower as its all under the floor until it pops out of the wall in the cubicle itself?
The only place I can think of is the cupboard on the floor below or do showers not have service valves?
Its a combi boiler system so no tanks feeding the water supply

 

[PrenticeBoyofDerry]

I'm wondering where he can put the service valve to the shower as its all under the floor until it pops out of the wall in the cubicle itself?
The only place I can think of is the cupboard on the floor below or do showers not have service valves?

If it is a cubicle shower, rather than a bath-shower it is normally difficult to isolate locally, unless pipe comes up from an exposed location or if the pipes are routed from the reverse side of the wall.
I have had on occasions been able to divide the bathroom supply from the rest of the house, so only the bathroom is isolated, that would be one option but all bathroom appliance will be isolated if the shower requires maintenance.

 

[dilalio]

Maybe the shower valve has built in isolators? Some have a slotted screw, ballofix type on the hot & cold inlets, that can be accessed when the cover plate is removed!?

 

[shardy]

The shower we chose is an exposed thermostatic bar type. Sounds like the best place to put the isolator valve might be on the feed pipes in the built in cupboard below