Bungalow Piping Manifold and Air

[umiq88]

New build looking to install mains water and UVC centrally and run piping through attic to kitchen, WCs etc. 

 

In my head sounds like a great idea for access, maintenance etc. however thinking about it am I going to need a air vents on every line or will a pressurised system push the air out?

[JohnMo]

Our cylinder is in an upstairs plant room, the pipes go along in the ceiling and down into the utility to the hot manifold and then back up and down to the wet rooms, never seen an issue.

[Jenki]

You have to look at all systems at the same time. Where will your air tightness layer be? You say bungalow, so assume single level no attic rooms?

In my build, a  true bungalow with cold roof, I ran conduit in the floor insulation for all services required, shower, bath, basin, WC, kitchen sink, WC, basin, utility room etc. then all pipes go under the floor from a manifold in the plant room. This allows for less penetrations into the airtightness layer.

All my cables run in a service void at ceiling level and the only penetrations into the ceiling are 7 MVHR vents, plus 4 to connect to the MVHR unit. And 4 cables for solar, loft light, and a socket.

 

[ProDave]

With an UVC in the middle, think where you are going to route the D2 discharge pipe.  That is to vent possibly boiling hot water being vented in the event of a fault.  There are strict rules on how it can be laid.  It either has to vent out of the building or under some circumstances into a drain pipe stack.  That will almost certainly need something building in for it at foundation time.

[umiq88]

Thanks guys 

 

Location of UVC is a 800x1900 cupboard in the hall. Plan to make floor lower and put in floor drain. All CH and DW pipes etc will come from here and can be isolated and drained down. Looks like conduit in the floor solves all problems.

 

Build is normal bungalow no upstairs. Attic vented to outside.

 

Cabling will be chased into walls and go up to attic but will have to think about how to seal. Same for penetrations around lights.

[Russell griffiths]

Why put something in the floor where you cannot get access to it, when you have a large void over the entire house that is being unused 

I’ve built two bungalow type houses and everything goes up in the loft for easy placement and easy maintenance later. 

[umiq88]

On 21/03/2024 at 11:27, Russell griffiths said:

Why put something in the floor where you cannot get access to it, when you have a large void over the entire house that is being unused 

I’ve built two bungalow type houses and everything goes up in the loft for easy placement and easy maintenance later. 

 

My cylinder and manifolds will be in the house. How do you deal with air in the pipes? 

 

Jenki makes a good point about air tightness which can be solved but is another consideration.

[Russell griffiths]

What air in pipes. 
does your house now not have pipes in the loft. 
the bungalow I live in now certainly has pipes that go from a cylinder up into the loft and then down to a bedroom 

 

[Jenki]

On 25/03/2024 at 17:37, Russell griffiths said:

What air in pipes. 
does your house now not have pipes in the loft. 
the bungalow I live in now certainly has pipes that go from a cylinder up into the loft and then down to a bedroom 

 

I put conduit under the slab for all pipes terminated at a manifold in the plant room. All plastic pipe with no joints. No pipes in the loft. Just MVHR, and ethernet cable, coaxial, power.

[umiq88]

@Russell griffiths

 

If the pipes start in the house, go up into the attic and then back down into the house then you create a pocket for air to gather. 

 

On a conventional gravity fed system this would air lock and you would either get no flow or reduced flow.

 

I have not lived in or worked on many pressurised systems. Surely the same problem exists unless the pressure is enough to drive water through the system. 

[Russell griffiths]

As far as I’m aware in a mains fed hot water tank this problem doesn’t exist. 

[sharpener]

When I extended the rainwater supply I put in 15mm polypipe mains water pipes to supply drinking water to the bathrooms. They go up into the loft and down again. I didn't consider the possibility of air locks at the time and there has never been a problem since.

[Nickfromwales]

On 26/03/2024 at 12:25, umiq88 said:

@Russell griffiths

 

If the pipes start in the house, go up into the attic and then back down into the house then you create a pocket for air to gather. 

 

On a conventional gravity fed system this would air lock and you would either get no flow or reduced flow.

 

I have not lived in or worked on many pressurised systems. Surely the same problem exists unless the pressure is enough to drive water through the system. 

I've fitted scores of UVC's and you can 100% relax. Zero trapped air problems will occur here, ever. Blast them through once, go to pub, celebrate. 😎