My mum and dad's garage flat roof has a gutter at one end that runs via
a drainpipe into a grid that just leads into a soakaway. Needless to
say, said soakaway silted up years ago; and now, whenever it rains
(which it has done rather a lot of recently), their patio floods nicely.
The nearest downpipe from the roof goes between their house and their
neighbour's between two conservatories, and wouldn't be easy to connect
to (especially since the water would be required to flow uphill); but
there is a soil stack about eight feet away. Can it be connected to
that? Or is a water butt the best (and only legal) option?

Dan S. MacAbre wrote:
My mum and dad's garage flat roof has a gutter at one end that runs
via a drainpipe into a grid that just leads into a soakaway. Needless to
say, said soakaway silted up years ago; and now, whenever
it rains (which it has done rather a lot of recently), their patio
floods nicely. The nearest downpipe from the roof goes between their
house and their neighbour's between two conservatories, and wouldn't
be easy to connect to (especially since the water would be required
to flow uphill); but there is a soil stack about eight feet away. Can it
be connected to that? Or is a water butt the best (and only
legal) option?

It can't really go into the stack as the sewer smells will end up in the
gutter of the garage.

A water butt would probably be the easiest solution. there are others but
they would cost a few quid more than a butt and require a bit of work

Phil L wrote:
Dan S. MacAbre wrote:
My mum and dad's garage flat roof has a gutter at one end that runs
via a drainpipe into a grid that just leads into a soakaway. Needless to
say, said soakaway silted up years ago; and now, whenever
it rains (which it has done rather a lot of recently), their patio
floods nicely. The nearest downpipe from the roof goes between their
house and their neighbour's between two conservatories, and wouldn't
be easy to connect to (especially since the water would be required
to flow uphill); but there is a soil stack about eight feet away. Can it
be connected to that? Or is a water butt the best (and only
legal) option?

It can't really go into the stack as the sewer smells will end up in the
gutter of the garage.


Good point :-) There are lots of other things going into it, since it
lines up nicely with the kitchen, but they all have traps.

A water butt would probably be the easiest solution. there are others but
they would cost a few quid more than a butt and require a bit of work


Makes sense. But if it carries on raining like this, they'll be
emptying it daily.

Chris Hogg wrote:
On Tue, 12 Jul 2016 09:16:22 +0100, "Dan S. MacAbre"
wrote:

Phil L wrote:
Dan S. MacAbre wrote:
My mum and dad's garage flat roof has a gutter at one end that runs
via a drainpipe into a grid that just leads into a soakaway. Needless to
say, said soakaway silted up years ago; and now, whenever
it rains (which it has done rather a lot of recently), their patio
floods nicely. The nearest downpipe from the roof goes between their
house and their neighbour's between two conservatories, and wouldn't
be easy to connect to (especially since the water would be required
to flow uphill); but there is a soil stack about eight feet away. Can it
be connected to that? Or is a water butt the best (and only
legal) option?

It can't really go into the stack as the sewer smells will end up in the
gutter of the garage.


Good point :-) There are lots of other things going into it, since it
lines up nicely with the kitchen, but they all have traps.

A water butt would probably be the easiest solution. there are others but
they would cost a few quid more than a butt and require a bit of work


Makes sense. But if it carries on raining like this, they'll be
emptying it daily.

You could bodge it like this: http://tinyurl.com/zqhj4xv but two

I'd sort of imagined something like that, and it's interesting to see it
done. The roof doesn't get much stuff on it - there are no trees
nearby, and no gravel; but I remember that our own gutters were once
blocked by soil (lovely quality, too), and I've no idea where that came
from. Probably rotten moss.

issues. 1) the trap would soon get blocked by debris off the roof, and
2) your local water authority might not take kindly to having
rainwater discharged into the sewer system. AIUI some WA's are OK with
that, but others not, as it may overload the sewerage system's
capacity and raw sewage may get forced up through manholes etc.

The best option is to dig out and redo the soakaway.

It sounds like one hell of a job, but I'll see what I can find out.
I've no idea what I'd find down there. It's at the bottom of a natural
depression anyway, so I've no idea how it was ever expected to work.

On Tuesday, 12 July 2016 09:16:24 UTC+1, Dan S. MacAbre wrote:
Phil L wrote:
Dan S. MacAbre wrote:
My mum and dad's garage flat roof has a gutter at one end that runs
via a drainpipe into a grid that just leads into a soakaway. Needless to
say, said soakaway silted up years ago; and now, whenever
it rains (which it has done rather a lot of recently), their patio
floods nicely. The nearest downpipe from the roof goes between their
house and their neighbour's between two conservatories, and wouldn't
be easy to connect to (especially since the water would be required
to flow uphill); but there is a soil stack about eight feet away. Can it
be connected to that? Or is a water butt the best (and only
legal) option?

It can't really go into the stack as the sewer smells will end up in the
gutter of the garage.


Good point :-) There are lots of other things going into it, since it
lines up nicely with the kitchen, but they all have traps.

A water butt would probably be the easiest solution. there are others but
they would cost a few quid more than a butt and require a bit of work


Makes sense. But if it carries on raining like this, they'll be
emptying it daily.

If you fitted a trap there'd still be the issue that a blockage would bring sewage out into the garden - but historic houses are often plumbed that way. Water butt or soakaway sound better.

FWIW water can drain uphill if it has a head of water pushing it. But you don't want that outdoors, it'll freeze and split the pipe.


NT

wrote:
On Tuesday, 12 July 2016 09:16:24 UTC+1, Dan S. MacAbre wrote:
Phil L wrote:
Dan S. MacAbre wrote:
My mum and dad's garage flat roof has a gutter at one end that runs
via a drainpipe into a grid that just leads into a soakaway. Needless to
say, said soakaway silted up years ago; and now, whenever
it rains (which it has done rather a lot of recently), their patio
floods nicely. The nearest downpipe from the roof goes between their
house and their neighbour's between two conservatories, and wouldn't
be easy to connect to (especially since the water would be required
to flow uphill); but there is a soil stack about eight feet away. Can it
be connected to that? Or is a water butt the best (and only
legal) option?

It can't really go into the stack as the sewer smells will end up in the
gutter of the garage.


Good point :-) There are lots of other things going into it, since it
lines up nicely with the kitchen, but they all have traps.

A water butt would probably be the easiest solution. there are others but
they would cost a few quid more than a butt and require a bit of work


Makes sense. But if it carries on raining like this, they'll be
emptying it daily.

If you fitted a trap there'd still be the issue that a blockage would bring sewage out into the garden - but historic houses are often plumbed that way. Water butt or soakaway sound better.

I think I'll try the water butt first, and see how they get on with that.

FWIW water can drain uphill if it has a head of water pushing it. But you don't want that outdoors, it'll freeze and split the pipe.


NT

On Mon, 11 Jul 2016 14:28:32 +0100, "Dan S. MacAbre"
wrote:

My mum and dad's garage flat roof has a gutter at one end that runs via
a drainpipe into a grid that just leads into a soakaway. Needless to
say, said soakaway silted up years ago; and now, whenever it rains
(which it has done rather a lot of recently), their patio floods nicely.
The nearest downpipe from the roof goes between their house and their
neighbour's between two conservatories, and wouldn't be easy to connect
to (especially since the water would be required to flow uphill); but
there is a soil stack about eight feet away. Can it be connected to
that? Or is a water butt the best (and only legal) option?
The whole rear roof on my Victorian house discharges into the main
sewer, via a gully/trap where the kitchen waste water goes. Been like
this since the house was built.

On 12/07/2016 10:52, Davidm wrote:

The whole rear roof on my Victorian house discharges into the main
sewer, via a gully/trap where the kitchen waste water goes. Been like
this since the house was built.

Yes but (a) there is a trap - and one which is relatively easy to clear
of leaves, moss, dead rats and other dross; and (b) in later times many
houses were built with separate rain water and sewage systems.

--
Robin
reply-to address is (intended to be) valid

Dan S. MacAbre wrote:
Chris Hogg wrote:

The best option is to dig out and redo the soakaway.

It sounds like one hell of a job, but I'll see what I can find out.
I've no idea what I'd find down there. It's at the bottom of a
natural depression anyway, so I've no idea how it was ever expected
to work.

It doesn't need to be huge.
And don't fall for the 'hole full of rocks' method as these work for about a
month, after which they are simply 'rocks with soil inbetween them' IE,
ground that the rainwater passes over on it's way to somewhere else,
probably your patio.

You can wrap two plastic beer crates in weed membrane (several layers and
well taped), bury these and run the outlet into these underground. If the
gutters get mossy, this method will fill the soakaway with moss in short
time, so maybe better to run the outlet onto the top of them, the top can be
disguised with half bricks or broken paving.

I built a small one a few days ago on a site I'm working on, I used two
plastic manhole rings 450mm by250mm sitting on 75mm stone 100mm deep over
the subsoil, which is actually sand.
The thing ended up 450(W) X 500(H). I ran an underground drain into the top
then cut a paving slab to fit the top, then put 100mm concrete over the lot

Phil L wrote:
Dan S. MacAbre wrote:
Chris Hogg wrote:

The best option is to dig out and redo the soakaway.

It sounds like one hell of a job, but I'll see what I can find out.
I've no idea what I'd find down there. It's at the bottom of a
natural depression anyway, so I've no idea how it was ever expected
to work.

It doesn't need to be huge.
And don't fall for the 'hole full of rocks' method as these work for about a
month, after which they are simply 'rocks with soil inbetween them' IE,
ground that the rainwater passes over on it's way to somewhere else,
probably your patio.

You can wrap two plastic beer crates in weed membrane (several layers and
well taped), bury these and run the outlet into these underground. If the
gutters get mossy, this method will fill the soakaway with moss in short
time, so maybe better to run the outlet onto the top of them, the top can be
disguised with half bricks or broken paving.

I built a small one a few days ago on a site I'm working on, I used two
plastic manhole rings 450mm by250mm sitting on 75mm stone 100mm deep over
the subsoil, which is actually sand.
The thing ended up 450(W) X 500(H). I ran an underground drain into the top
then cut a paving slab to fit the top, then put 100mm concrete over the lot


Thanks, that sounds interesting, and easy to examine in the future.
Presumably, it relies on having good (i.e. not clay) soil?

On Mon, 11 Jul 2016 14:28:32 +0100, Dan S. MacAbre wrote:

My mum and dad's garage flat roof has a gutter at one end that runs via
a drainpipe into a grid that just leads into a soakaway. Needless to
say, said soakaway silted up years ago; and now, whenever it rains
(which it has done rather a lot of recently), their patio floods nicely.
The nearest downpipe from the roof goes between their house and their
neighbour's between two conservatories, and wouldn't be easy to connect
to (especially since the water would be required to flow uphill); but
there is a soil stack about eight feet away. Can it be connected to
that? Or is a water butt the best (and only legal) option?

Leaving aside the need for some kind of cleanable trap to prevent sewer
gasses leaking out, the answer is "it depends".

If the rain water from your main house already empties into the main sewer
then it is probably O.K. to use the main sewer - but this is at the
discretion of your local water authority.

If your main house drains into a separate storm water drain one or more
soakaways then they are unlikely to permit you to use the main sewer.
However you could always ask.

A water butt seems to me to be only delaying the problem.
Once it has filled up then you will get exactly the same volume of water
off the roof wanting to go to exactly the same place.

Fixing or replacing the soakaway is probably your best bet (but see above).

Oh, and on the subject of traps - normally a waste water trap outside is
sunk into the ground and connected to the drain underground. Sinks and the
like have a U bend trap fitted underneath then a direct connection to the
soil pipe pipe (inside or out).

I am trying to find a reason not to fit a trap half way up the garage wall
so that your gutter drains into it but you can still connect to the soil
stack above the ground. As long as it is in a place where you can service
it easily.


Cheers


Dave R


--
Windows 8.1 on PCSpecialist box

Dan S. MacAbre wrote:

Thanks, that sounds interesting, and easy to examine in the future.
Presumably, it relies on having good (i.e. not clay) soil?

It works best without clay soil yes, sand, chalk, stone etc will drain
farily quickly, clay tends to hold it.

All you are doing is creating a holding tank which fills during a heavy
downpour and then seeps away later

On 11/07/2016 14:28, Dan S. MacAbre wrote:
My mum and dad's garage flat roof has a gutter at one end that runs via
a drainpipe into a grid that just leads into a soakaway. Needless to
say, said soakaway silted up years ago; and now, whenever it rains
(which it has done rather a lot of recently), their patio floods nicely.
The nearest downpipe from the roof goes between their house and their
neighbour's between two conservatories, and wouldn't be easy to connect
to (especially since the water would be required to flow uphill); but
there is a soil stack about eight feet away. Can it be connected to
that? Or is a water butt the best (and only legal) option?
Water butts fill up, however if you connect a length of drip/leaky hose
laid down the garden in a suitable location (a soak away without any
digging) you can leave the tap turned on during the wetter months so
that the butt drains out and can normally cope with the next rainfall
without overflowing and then when it's drier you can turn the tap off to
conserve the water for use when you need it.

Peter