Hello,

Imagine a patio surrounded by a retaining wall, house and garden are
at two different levels. So patio will be against the house and
retaining wall will be needed as currently there is a slope down to
the grass. Next to house is an existing rainwater trapped gully.

My idea is to slope the patio towards this gully, so all rainwater
will drain away properly, as patio will be surrounded by a retaining
wall some drainage is definitely needed.

But the thought of sloping the patio towards the house seems counter-
intuitive.

But will it cause any problems?

Thanks,

Graham

On Sep 23, 9:12 am, Graham Jones wrote:
Hello,

Imagine a patio surrounded by a retaining wall, house and garden are
at two different levels. So patio will be against the house and
retaining wall will be needed as currently there is a slope down to
the grass. Next to house is an existing rainwater trapped gully.

My idea is to slope the patio towards this gully, so all rainwater
will drain away properly, as patio will be surrounded by a retaining
wall some drainage is definitely needed.

But the thought of sloping the patio towards the house seems counter-
intuitive.

But will it cause any problems?

such as?

what is the height difference from inside to outside?
what age is the house? what is the outer wall construction? is there a
DPC visible on the outside? if so what height is it above proposed
patio level?

Jim K

On Sep 23, 9:41*am, Jim K wrote:
On Sep 23, 9:12 am, Graham Jones wrote:

Hello,

Imagine a patio surrounded by a retaining wall, house and garden are
at two different levels. So patio will be against the house and
retaining wall will be needed as currently there is a slope down to
the grass. Next to house is an existing rainwater trapped gully.

My idea is to slope the patio towards this gully, so all rainwater
will drain away properly, as patio will be *surrounded by a retaining
wall some drainage is definitely needed.

But the thought of sloping the patio towards the house seems counter-
intuitive.

But will it cause any problems?

such as?

what is the height difference from inside to outside?
what age is the house? what is the outer wall construction? is there a
DPC visible on the outside? if so what height is it above proposed
patio level?

Jim K

Hello Jim,

There is currently a path next to the house, the patio will be to the
same level as this which is two bricks below the dpc.

Graham

On Sep 23, 9:46 am, Graham Jones wrote:
On Sep 23, 9:41 am, Jim K wrote:



On Sep 23, 9:12 am, Graham Jones wrote:

Hello,

Imagine a patio surrounded by a retaining wall, house and garden are
at two different levels. So patio will be against the house and
retaining wall will be needed as currently there is a slope down to
the grass. Next to house is an existing rainwater trapped gully.

My idea is to slope the patio towards this gully, so all rainwater
will drain away properly, as patio will be surrounded by a retaining
wall some drainage is definitely needed.

But the thought of sloping the patio towards the house seems counter-
intuitive.

But will it cause any problems?

such as?

what is the height difference from inside to outside?
what age is the house? what is the outer wall construction? is there a
DPC visible on the outside? if so what height is it above proposed
patio level?

Jim K

Hello Jim,

There is currently a path next to the house, the patio will be to the
same level as this which is two bricks below the dpc.

Graham

so if i get this right the land slopes away from the house? so why not
let it continue to absorb all the rain that comes off the patio? (or
are you proposing to completely pave over the mentioned grass/garden?)

Jim K

Graham Jones wrote:

Hello,

Imagine a patio surrounded by a retaining wall, house and garden are
at two different levels. So patio will be against the house and
retaining wall will be needed as currently there is a slope down to
the grass. Next to house is an existing rainwater trapped gully.

My idea is to slope the patio towards this gully, so all rainwater
will drain away properly, as patio will be surrounded by a retaining
wall some drainage is definitely needed.

But the thought of sloping the patio towards the house seems counter-
intuitive.

But will it cause any problems?

The last house we bought had a similar issue, garden sloping towards
the house, 2' drop onto patio which sloped towards and connected to the
house with a small drainage channel at the base of the house wall.
There were two steps up to get into the house. The dpc on that wall
was about 10" or so above the patio level and we had no problems
whatsoever, except for 'the usual' .. leaves/debris blocking the
channel and subsequent drain ..

I suggest checking where the dpc for the house wall is and if there's
any chance of water on the patio breaching it then it might be better
looking for another solution.

--
Paul - xxx

In message
,
Graham Jones writes
Hello,

Imagine a patio surrounded by a retaining wall, house and garden are
at two different levels. So patio will be against the house and
retaining wall will be needed as currently there is a slope down to
the grass. Next to house is an existing rainwater trapped gully.

My idea is to slope the patio towards this gully, so all rainwater
will drain away properly, as patio will be surrounded by a retaining
wall some drainage is definitely needed.

But the thought of sloping the patio towards the house seems counter-
intuitive.

But will it cause any problems?

I don't see why. We have a tarmac front yard which drains to a 6" gulley
and then passes under the house. Obviously blockage of the grid or pipe
and a deluge will eventually flood the house.

You may be able to arrange your patio slope such that ponding will
overflow elsewhere before things get serious:-)

regards

--
Tim Lamb

"Graham Jones" wrote in message
...
Hello,

Imagine a patio surrounded by a retaining wall, house and garden are
at two different levels. So patio will be against the house and
retaining wall will be needed as currently there is a slope down to
the grass. Next to house is an existing rainwater trapped gully.

My idea is to slope the patio towards this gully, so all rainwater
will drain away properly, as patio will be surrounded by a
retaining
wall some drainage is definitely needed.

But the thought of sloping the patio towards the house seems
counter-
intuitive.

But will it cause any problems?

Thanks,

Graham

Run a length of ACCO surface channel drain on the lower edges and on
into your trapped gully, that way heavy downpours are coped with
easily.

AWEM
(who has laid more ACCO drain this year than he cares to remember!!!)

On Fri, 23 Sep 2011 01:12:24 -0700, Graham Jones wrote:

Hello,

Imagine a patio surrounded by a retaining wall, house and garden are at
two different levels. So patio will be against the house and retaining
wall will be needed as currently there is a slope down to the grass.
Next to house is an existing rainwater trapped gully.

My idea is to slope the patio towards this gully, so all rainwater will
drain away properly, as patio will be surrounded by a retaining wall
some drainage is definitely needed.

But the thought of sloping the patio towards the house seems counter-
intuitive.

So why not take feed from the gully to a new drain point furthest from
the house and put a new/extra gully in there? That way if it ponds it is
away from the house.

You may even be inclined to put weep holes in the retaining wall so it
can discharge onto the grass.

Or have I misunderstood the layout?