Unvented D1& D2 terminations

[TFGplumbing]

Hiya guys

aside from a trapped gully what other acceptable terminations are available for unvented discharge pipework?

Can you discharge into an internal soil stack? via waste pipe and hot tuns?

Thanks in advance

If anyone has some g3 documentation that would be handy

 

[ShaunCorbs]

Can be internally but need a hep 20 trap etc

But d2 needs to be in push fit clipped well or solvent weld high temp etc

 

[TFGplumbing]

Thanks Shaun, The builder has tiled in the soil stack only leaving one strap on boss connection, intended for the basin and unvented cylinder discharge.

Am I right in assuming that the cylinder will need a seperate strap on boss?

 

[ShaunCorbs]

Thanks Shaun, The builder has tiled in the soil stack only leaving one strap on boss connection, intended for the basin and unvented cylinder discharge.

Am I right in assuming that the cylinder will need a seperate strap on boss?

No aslong as it's designed to take both loads and high temp rating

 

[Scott_D]

It should be a separate pipe to the soil stack

 

[Welder]

You can indeed use a hotun and go into the internal stack. Is the UVC direct or indirect? Direct are potentialy more problematic for high discharge temps. I know the test for such things is a CONTINUAL discharge of 95 deg C water for something like an hour!! Their point apparently is that two immersions could run rogue for an hour!

Personally, I think its utter tosh and all they are doing is making it up as they go along. That said I'm a cynical old heffer

 

[kozak1968]

It would be nice if they do updates on regs for unvented cylinders. I renewed mine last month and a couple of things caught my eye, high level termination is allowed back against the wall and discharge now has to be lagged if run external or in an unheated area.

 

[Welder]

Really? So how the dickens do we stay abreast of these (significant) changes?

 

[Last Plumber]

Read pages 23 and 24 of this link.

 

[ShaunCorbs]

Why the disagree Chris ?

 

[chris watkins]

Why the disagree Chris ?

You can't combine wastes Shaun it states it must be a separate dedicated run, I guess in case the waste pipe became restricted or blocked with normal use of the sanitary appliance.
Part G3 3.60 b & d.

I am also not aware of a solvent weld plastic in common use by plumbers that is suitable. If run is plastic it should be polybutylene (PB) or cross linked polyethylene (PE-X) or to Class S of BS 7291-3:2006 albeit that I think that BS has been superseded.

 

[ShaunCorbs]

So that means you can't use the stack for anything else but the unvented

Also that could be said for a normal dedicated line for the unvented terminal end could become blocked etc

Also there are a lot of 30 plus l undersink water heaters teed into drain lines that manufacturer instructions and building regs that are happy / acceptable with it

Also haven't you come across high temp solvent waste systems uses a different high temp glue to the normal stuff

 

[chris watkins]

So that means you can't use the stack for anything else but the unvented
No, not the stack just the waste pipes. It just states we need to demonstrated that the soil stack is capable of safety withstanding temp of discharge, not sure how was are supposed to do that but I normally say if it is vertical, clipped & vented directly so that there is air flow it should be OK.
Also that could be said for a normal dedicated line for the unvented terminal end could become blocked etc
Yes but you must admit teeing in to a waste pipe increases the risk dramatically.

Also there are a lot of 30 plus l undersink water heaters teed into drain lines that manufacturer instructions and building regs that are happy / acceptable with it
Not sure what you mean, I have not seen them but as we know two wrongs don't make it right & policing is weak. I am just quoting the Regulations Approved Document as I see it.

Also haven't you come across high temp solvent waste systems uses a different high temp glue to the normal stuff.
Can't remember but does it comply with BS7291-1,2&3:2006 if so fine it could be used. The problem is by stating that a solvent weld system acceptable the uneducated may be lead to believe that all S/W systems are OK.

The devil is always in the detail for example- you & I know that if Terrian or Anchor S/W plastic system was used & clipped frequently it would be capable of withstanding the temperatures whereas a thin wall type would not (poly & the like), the trouble is the BS dose not distinguish between them however all PB plastic pipe is capable, however cheap.

 

[ShaunCorbs]

The devil is always in the detail for example- you & I know that if Terrian or Anchor S/W plastic system was used & clipped frequently it would be capable of withstanding the temperatures whereas a thin wall type would not (poly & the like), the trouble is the BS dose not distinguish between them however all PB plastic pipe is capable, however cheap.

whats the difference in the stack blocking, ive seem more stacks /main drainage block rarther than sinks same risk either way if you see where im coming from

i dont sorry esp if its something like a 2" waste (heat resistant of course)

manufacture instructions / spec overrule bs

and think the spec is 90dc for 30 mins

 

[Old Account]

The devil is always in the detail for example- you & I know that if Terrian or Anchor S/W plastic system was used & clipped frequently it would be capable of withstanding the temperatures whereas a thin wall type would not (poly & the like), the trouble is the BS dose not distinguish between them however all PB plastic pipe is capable, however cheap.

Where to get the high temp pipes and fittings .

 

[ShaunCorbs]

Where to get the high temp pipes and fittings .

LMGTFY

 

[Old Account]

LMGTFY

Thank you very much. Is there only a chance to buy online?

 

[ShaunCorbs]

or special order from stockists

 

[chris watkins]

The push fit pipe sold in B&Q, Tool station etc. as well a Wilaims & Co & other merchants is all suitable as it is polybutylene (PB) it is also cheap! albeit not great as waste pipe in my humble.

At the end of the day by using it no one can argue that I haven't met the requirements of the Building Regulations Part G3 (the Law) not even a BC officer and that is good enough reason for me.