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Jeff
 
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Default Plumbing Question

Hi All,

I'm helping out with the re-plumbing of a house, the house has been gutted
and significantly extended. So rather than adding a new bathroom and just
joining the pipe work onto the existing pipes, I'm in the situation of
there's the domestic supply pipe we need a bathroom here and here etc.

My first question is really about the sizing of the pipe, the house in
question will have 3 bathrooms ( I've been told it has low mains pressure);

Up-stairs bathroom 1 bath, 1 w.c, 1 basin, 1 mixer shower.
Downstairs cloak room with 1 basin, 1 w.c
Downstairs shower room with 1 basin, 1 w.c, 1 mixer shower

The owner has been advised by the builder that a 15mm supply will be
adequate, now I'm no plumber but when you also include the sink, washing
machine and dish washer into the equation and not forgetting the supply to
the combi boiler. I don't think this is right, gut feeling is 22mm (boiler
has 22mm connection anyway) reducing down to 15mm at the furthest point
seems to be more sensible. Anyone any thoughts on this?

My second question is more straight forward. Because of the location of one
of the toilets, I need to lay a horizontal run of soil & waste pipe which
will have 2 toilets on it, what fall should the pipe have?

And lastly on the above soil & waste pipe, I believe its ok to use a
strap-on boss to join the basin waste to it as long as its not within 200mm
of the wc connection or does this only apply to vertical soil pipes?

Hope someone can shed some light on these questions.

Many thanks.

Jeff







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Christian McArdle
 
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The owner has been advised by the builder that a 15mm supply will be
adequate,


As a general rule, I've only used 15mm for basins, toilets and appliances.
Showers and baths get 22mm. However, you appear to be installing a combi
boiler. If the mains pressure really is low, you should check that it is
still enough for a mains pressure installation. What sort of flow rate can
be supplied?

Christian.



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Jeff
 
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Default Plumbing Question

Thanks for the prompt reply Christian.

The short answer is I don't know, but you have a point.
The longer answer is I was asked to go down and give them a hand, I didn't
know they wanted me to plan the system, they've already bought the boiler a
Valiant eco 82? the outside temporary tap fills a kettle pretty quickly, but
I didn't think to check the flow rate...too many other problems to sort out

Cheers,

Jeff


"Christian McArdle" wrote in message
. net...
The owner has been advised by the builder that a 15mm supply will be
adequate,


As a general rule, I've only used 15mm for basins, toilets and appliances.
Showers and baths get 22mm. However, you appear to be installing a combi
boiler. If the mains pressure really is low, you should check that it is
still enough for a mains pressure installation. What sort of flow rate can
be supplied?

Christian.





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Roger Mills
 
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Default Plumbing Question


"Jeff" wrote in message
...
Hi All,

I'm helping out with the re-plumbing of a house, the house has been gutted
and significantly extended. So rather than adding a new bathroom and just
joining the pipe work onto the existing pipes, I'm in the situation of
there's the domestic supply pipe we need a bathroom here and here etc.

My first question is really about the sizing of the pipe, the house in
question will have 3 bathrooms ( I've been told it has low mains

pressure);

Up-stairs bathroom 1 bath, 1 w.c, 1 basin, 1 mixer shower.
Downstairs cloak room with 1 basin, 1 w.c
Downstairs shower room with 1 basin, 1 w.c, 1 mixer shower

The owner has been advised by the builder that a 15mm supply will be
adequate, now I'm no plumber but when you also include the sink, washing
machine and dish washer into the equation and not forgetting the supply to
the combi boiler. I don't think this is right, gut feeling is 22mm (boiler
has 22mm connection anyway) reducing down to 15mm at the furthest point
seems to be more sensible. Anyone any thoughts on this?

My second question is more straight forward. Because of the location of

one
of the toilets, I need to lay a horizontal run of soil & waste pipe which
will have 2 toilets on it, what fall should the pipe have?

And lastly on the above soil & waste pipe, I believe its ok to use a
strap-on boss to join the basin waste to it as long as its not within

200mm
of the wc connection or does this only apply to vertical soil pipes?

Hope someone can shed some light on these questions.

Many thanks.

Jeff







Low water pressure . . . 3 bathrooms . . . . .combi boiler - forget it!!

If I were doing it, I would use a conventional boiler and have a large hot
water storage tank - and an even larger cold water storage tank. I would
plumb the hot water system in 22mm - except for a 28mm feeder pipe from the
header tank to the hot tank. I would use mains cold water - probably plumbed
in 15mm - to the kitchen sink, washbasins and toilets - and to fill the
storage tank. I would use stored cold water, plumbed in 22mm for the baths
and showers - and would use shower pumps to boost the pressure/flow to the
showers.

The above is based on gut feel rather than detailed science - but seems
reasonable to me.

I will leave others to comment on what you can and can't do with regard to
the waste water connections.

Roger



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Dave Liquorice
 
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Default Plumbing Question

On Mon, 1 Dec 2003 11:28:14 -0000, Jeff wrote:

The owner has been advised by the builder that a 15mm supply will be
adequate,


"adequate" in that some water will come out of the taps some of the
time. I'd plumb all the water in 22mm T'ing to 15mm on visible feeds,
basins, loos etc. Especially with a combi in the equation.

I need to lay a horizontal run of soil & waste pipe which will have
2 toilets on it, what fall should the pipe have?


1:40 rings a bell. There are rules about the maximum effective length
on "horizontal" soil runs as well. Not effective length each bend
counts as x feet etc...

--
Cheers
Dave. pam is missing e-mail



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