Merry Christmas!

Following on from my previous queries about our badly designed and executed
soil ventilation stack situation....

I'm liking the idea of capping off both of our soil stacks with access caps
and using Hepvo waste traps on all of the sinks, baths, shower etc. This
will prevent me putting in what will likely be unreliable air admittance
valves and will also stop any warm damp air from entering the loft and
causing damp, dry rot etc situations from becoming a problem in the future.

It's going to be a PITA to do, but I'd rather do the job done right first
time.

Would I have to change all of the following p-traps with hepvo's or just
some?:

Soil stack #1 services:
1x sink in utility
1x sink in kitchen
1x basin in en-suite
1x shower in en-suite
(plus WC in en-suite)

Soil stack #2 services:
1x basin in d/s toilet
1x basin in bathroom
1x bath
(plus WC in d/s toilet and bathroom)

Many thanks.

On 25/12/10 10:26, Tom Pickles wrote:
Merry Christmas!

Following on from my previous queries about our badly designed and executed
soil ventilation stack situation....

I'm liking the idea of capping off both of our soil stacks with access caps
and using Hepvo waste traps on all of the sinks, baths, shower etc. This
will prevent me putting in what will likely be unreliable air admittance
valves and will also stop any warm damp air from entering the loft and
causing damp, dry rot etc situations from becoming a problem in the future.

It's going to be a PITA to do, but I'd rather do the job done right first
time.

Would I have to change all of the following p-traps with hepvo's or just
some?:

Soil stack #1 services:
1x sink in utility
1x sink in kitchen
1x basin in en-suite
1x shower in en-suite
(plus WC in en-suite)

Soil stack #2 services:
1x basin in d/s toilet
1x basin in bathroom
1x bath
(plus WC in d/s toilet and bathroom)

Many thanks.




Essentially one on each sub-line.

eg if you have washing-machine : dishwasher : sink

on the same bit of 50/40mm then on HepVO should do.

But you'd want another on the bathroom basin -especially if that
connects into a different stack or a stack adjacent to a loo (loos cause
big local suction effects).

You'll know if you don't have enough if any traps end up gurgling when
flushing loos - especially when flushing lots of bog paper as this forms
a fairly effective piston in the pipe.

So if you're not sure, leave the pipes exposed where applicable for a
month and see how it pans out in case you need an extra one, but if you
stick one on each logical sub branch, I don;t think you'll have any trouble.

I put one 110mm AAV behind the loo where the basin joints in nd that
does "fire" occasionally.

I didn't bother with any AAVs on the kitchen or bath branch and both,
although long branches in 50mm, drop into their personal grey-only 110mm
pipe that goes into a pit that also sports the open to air main vent.

What I'm saying there is think about the causes of suction and where
they are and what they impact in the locality and consider HepVOs there
first.

The Building Regs Approved Doc on drainage will also offer some general
guidance - AAVs and HepVOs perform exactly the same function, so where
the Docs say AAV, consider a HepVO.

Cheers

Tim

--
Tim Watts

On Dec 25, 10:26 am, "Tom Pickles" wrote:
Merry Christmas!

Following on from my previous queries about our badly designed and executed
soil ventilation stack situation....

I'm liking the idea of capping off both of our soil stacks with access caps
and using Hepvo waste traps on all of the sinks, baths, shower etc. This
will prevent me putting in what will likely be unreliable air admittance
valves and will also stop any warm damp air from entering the loft and
causing damp, dry rot etc situations from becoming a problem in the future.

It's going to be a PITA to do, but I'd rather do the job done right first
time.

Would I have to change all of the following p-traps with hepvo's or just
some?:

Soil stack #1 services:
1x sink in utility
1x sink in kitchen
1x basin in en-suite
1x shower in en-suite
(plus WC in en-suite)

Soil stack #2 services:
1x basin in d/s toilet
1x basin in bathroom
1x bath
(plus WC in d/s toilet and bathroom)

Many thanks.

But does it smell of sh1te in your loft? if not how do you know they
are the (working) soil stacks?
I would have thought one open stench pipe (clue in nickname) would
have been smelly but two....?!!? ;P

Personally I'd seriously be considering doing the job right once by
exposing enough of the stacks and seeing what they are currently
before going to the trouble and bother (and expense) of rigging HepVOs
allover the place.

It may be that in the boxing-in there may already be durgos (aka AAVs)
and the pipes you have in the loft are/were something else? or a
cockup that was just abandoned in the past?

Jim K

On Dec 25, 10:26*am, "Tom Pickles" wrote:

Following on from my previous queries about our badly designed and executed
soil ventilation stack situation....

I'm liking the idea of capping off both of our soil stacks with access caps
and using Hepvo waste traps on all of the sinks, baths, shower etc.

Be aware that using the Hepvo's essentially as air admittance valves
may result in them producing an unacceptable rasping sound as they
operate.

Mathew

On 25/12/10 23:57, Mathew Newton wrote:
On Dec 25, 10:26 am, "Tom wrote:

Following on from my previous queries about our badly designed and executed
soil ventilation stack situation....

I'm liking the idea of capping off both of our soil stacks with access caps
and using Hepvo waste traps on all of the sinks, baths, shower etc.

Be aware that using the Hepvo's essentially as air admittance valves
may result in them producing an unacceptable rasping sound as they
operate.

Mathew

I can't answer for HepVOs - but:

some unknown AAV in 110mm format I knew at work made a hell of a "parp"
when it operated.

My Floplast 110 AAV makes a discrete "blurp" and a 50mm Floplast AAV I
also have in the spares box seems virtually silent - though I've only
mouth operated it.

--
Tim Watts