Durgo size and height ??

[plumbtastic]

Hi

We're converting a barn with bedrooms and baths in the roof space with velux windows.

We don't want to penetrate the roof with unsightly soil vents. We're planning to put an open vent on the pipe run to the treatment plant (septic tank) and just have a durgo in the house.
Space is tight and siting the durgo is also a problem because of the direction of the joists etc and not wanting to move the wc forward from the wall whilst trying to incorporate a durgo which is what the plumber was talking about. First floor rooms have sloping roof so that does not help either with space as head height areas are at a premium.

I want to use the smallest possible diameter of durgo pipe ( maybe it can terminate in the stud wall with a grille. ) Is 50mm OK ?

Because of space problems I am also interested in some durgos that specify they can be fitted below flood level. What are the 'rules' about fitting these sorts of durgos ? eg Floplast AV110G Air Admittance Valves and Marley SVD2 and SVD3 say they can be fitted below the flood level but do not give any more information than that. What sort of height termination from the floor of the first floor can this be ?

I'm also seeing that there are external durgos which mean the soil pipe could go through the wall at ground floor ceiling height and then the exterior soil pipe would not have to rise too far and be an eyesore from the view from a window. What would the minimum height be if it was capped with an external durgo?

Thanks for looking.

 

[Sharp Point]

Can you put a diagram up of your proposal?

 

[plumbtastic]

Thanks for your reply.
I don't have a diagram unfortunately.

 

[Sharp Point]

Thanks for your reply.
I don't have a diagram unfortunately.

So you can’t draw one?

 

[plumbtastic]

What do you want on it ?

 

[Welder]

Hi

We're converting a barn with bedrooms and baths in the roof space with velux windows.

We don't want to penetrate the roof with unsightly soil vents.

Unfortunately, if you wish your property to perform properly and not smell of poo for eternity you will need to become more focussed on functionality than form. The clue is in your post: soil/vent.

Having an air admittance valve and no vent until the septic tank means you will get foul gases escaping into your living space at some point. With more than one bathroom please do not go down this route. With respect, this is a typical builder suggestion (little plumbing knowledge) but regardless of who suggested it it's a bad suggestion. Sorry.

 

[plumbtastic]

I can't really do a diagram until i know what is possible regarding the height of the the durgo because of the sloping ceiling. If it only needs to be 60cm, (ie the durgo that can go under the flood level), then i can put it in the eaves

 

[Welder]

I can't really do a diagram until i know what is possible regarding the height of the the durgo because of the sloping ceiling. If it only needs to be 60cm, (ie the durgo that can go under the flood level), then i can put it in the eaves

Thank you. Your reply reinforces my point. You have too little knowledge to even contemplate this course of action. Pretty or not.

 

[plumbtastic]

The BCO is ok with it in principle

 

[Welder]

The BCO is ok with it in principle

Now that made me laugh out loud. The BCOs generally have no clue about real world consequences. They tick boxes and walk away. The design is between you and whoever and so long as it does not contravene regs they could not give a hoot.

 

[Sharp Point]

The BCO is ok with it in principle

BCO knows absolute zero when it comes to drainage really, try approaching a well experienced plumber local to you and get his opinion.

 

[Sharp Point]

Your house NEEDS a 110mm open vent, it doesn’t matter which way it snakes above and into the loft to terminate through a tile vent( 900mm) above an opening into the building or through a gable end.

Oh and it has a slight fall back down to the vertical pipe, to drain condensation.

 

[plumbtastic]

If anyone else can answer my query about heights of durgo, then feel free to PM me. Cheers

 

[Welder]

If anyone else can answer my query about heights of durgo, then feel free to PM me. Cheers

Ahh the old, "I don't want to hear the truth routine."
"There are none so blind as those whose choose not to hear..."

 

[Sharp Point]

If anyone else can answer my query about heights of durgo, then feel free to PM me. Cheers

Okay then, to appease you. Just run a 110mm pipe straight off the back of your upstairs wc and down into the ground. Attach a strap on boss on the vertical pipe in 32mm and glue on a 32mm air admittance valve in a stud wall, then plaster over.

Job done

 

[Aire]

You should really follow the advice you've been given, in the future when you start getting bad smells in your house will your BCO be there to fix the problem for you?

To answer your question, durgo valves should be installed above the highest spill over level. Usually this is the basin which vary from 800 to 850mm so you'll want your durgo valve at around 900mm.

 

[plumbtastic]

Thanks folks. I hear what you say.

What are these below the flood level durgos all about then ?

 

[Aire]

Thanks folks. I hear what you say.

What are these below the flood level durgos all about then ?

Below flood level valves are designed to withstand higher pressures so in the event of the drains backing up they are less prone to leaking and flooding your house.

 

[king of pipes]

Come on guys be a bit more professional here the op has the option that he can get away with a vent at the septic tank and install one or more durgos? well we all know the drains need to be vented open at some point near the property I would advise you take our advise mr Plumb and fit one you do not necessarily need to penetrate the roof you could install tile vents they are not that unsightly and can be fitted out of sight . Kop

 

[Welder]

Come on guys be a bit more professional here the op has the option that he can get away with a vent at the septic tank and install one or more durgos? well we all know the drains need to be vented open at some point near the property I would advise you take our advise mr Plumb and fit one you do not necessarily need to penetrate the roof you could install tile vents they are not that unsightly and can be fitted out of sight . Kop

I genuinely respect your experience KOP, however I'm going to vehemently disagree with you on this one

There is no evidence that a single vent at the tank is even viable. The OP has been asked for a drawing but has not provided it. As the septic tank has to be a min distance from the property AND the property has multiple bathrooms an AAV cannot be classed as even a borderline 'acceptable' solution.

If you wish to advise it is, and of course the OP will jump on anything that reinforces his thought process, then that is your prerogative.

My, purely personal view, is that we have a poor enough reputation as an industry already so we can hardly complain about it in our own day to day dealing with customers if we sanction poor practice here.

 

[plumbtastic]

I am confused.
There are new housing schemes being built that build 4-5 houses sharing one open vent. The rest have durgos. the reason for this is to minimise work at heights and also maintain the thermal integrity of the roof. There seems to be a conflict in 'theory' here between seasoned plumbers and what the industry does.

Is your main beef that you do not trust durgos to do their job properly ?

 

[snowhead]

In no particular order.

Air admittamce valves, aka Durgos, do just that.
They let air in to prevent syphoning, when required, they don't vent the system.

Open vents are most effective at the head of the system, that way they guarantee to vent the whole system.

Just because others use 1 vent per system doesn't mean it's laid out in the same manner as your proposal.

Search on here for issues with AAVs failing and causing smells.

An open vent has no moving parts.

You'd need to consider how a potential buyer and or their surveyor will respond to the reliance on Durgos.

If it was my property I wouldn't have one in the place.
If I was installing for others and Durgos were the most economic and suitable way, I'd make sure they were fitted so they were accessible and would not cause too much nuisance when they fail.

 

[Sharp Point]

I am confused.
There are new housing schemes being built that build 4-5 houses sharing one open vent.

And I will pretty wager, that a lot of the above ground drainage that serves these houses are wrong, as a lot of plumbers don’t know what they’re doing. Yes a single vent could be used to serve multiple houses, as long as the configuration is correct. But nowadays these rabbit warren type estates that have drains going all over, that throws the multiple house method out of the window.
AAV are a get out of jail method and not good practice,

 

[Welder]

I am confused.
There are new housing schemes being built that build 4-5 houses sharing one open vent. The rest have durgos. the reason for this is to minimise work at heights and also maintain the thermal integrity of the roof. There seems to be a conflict in 'theory' here between seasoned plumbers and what the industry does.

Is your main beef that you do not trust durgos to do their job properly ?

The ONLY reason they install them is to reduce costs. End of.

 

[king of pipes]

I genuinely respect your experience KOP, however I'm going to vehemently disagree with you on this one

There is no evidence that a single vent at the tank is even viable. The OP has been asked for a drawing but has not provided it. As the septic tank has to be a min distance from the property AND the property has multiple bathrooms an AAV cannot be classed as even a borderline 'acceptable' solution.

If you wish to advise it is, and of course the OP will jump on anything that reinforces his thought process, then that is your prerogative.

My, purely personal view, is that we have a poor enough reputation as an industry already so we can hardly complain about it in our own day to day dealing with customers if we sanction poor practice here.

I agree with you Davy boi if you read again what I said the drains need a open vent not just one on the run I wouldn't do it . Kop