Options for improving drainage of an area near my house

[danlightbulb]

Hi,

I have water pooling in the area shown on the plan below. This is what caused my brickwork damage in this thread which Ive now had repaired and repointed.

But I need to sort the drainage somehow.

Does anyone have any advice please?

Water pools in the area shown in blue. The existing gulley, shown in red, is too high to drain surface water into.

So I either need to get water into the existing gully and therefore into the proper drainage system, shown in diagram as option 1, which would be the better option. But this would require me to expose the existing drains and fit a new gully trap and then a second patio drain trap in the blue area which links into the drainage system.

Or option B is I fit something like a channel drain or a patio drain and send the water away down the side of the outhouse and down into the garden area.

Or perhaps a third option is doing something with the ground levels to stop water pooling there at all. For example building a step so that section is higher and water can't pool there.


I attach some photos of the existing gulley.

 

[Mrs Ten Names]

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[danlightbulb]

Buy a drainage channel / Slot drain | Guttering Expert

A drainage channel/ slot drain ensures subtle drainage for your terrace or driveway. ✓In stock ✓Competitive prices. Click here for all drainage channels!

www.guttering-expert.co.uk

Thanks but not sure why you have just linked me to a website that doesn't even ship to UK, and I'm still none the wiser on how to actually install some additional drainage I.e what configuration to use in my diagram above?

 

[noseall]

Thanks but not sure why you have just linked me to a website that doesn't even ship to UK

In fairness to the poster, he's shown you an example of an Aco type linear drain, which are available at about a billion places in the UK. Like if he'd shown you a Canadian plasterboard, or an American door, or a Dutch window, or a French brick - he was probably hoping you could work it out.

With all the digging and disruption involved (regards any options), your best bet is to just re-lay the existing low slabs so that they fall to the nearest rainwater gully.

 

[danlightbulb]

In fairness to the poster, he's shown you an example of an Aco type linear drain, which are available at about a billion places in the UK. Like if he'd shown you a Canadian plasterboard, or an American door, or a Dutch window, or a French brick - he was probably hoping you could work it out.

With all the digging and disruption involved (regards any options), your best bet is to just re-lay the existing low slabs so that they fall to the nearest rainwater gully.

Ok thanks. I'm aware that either gulleys or acco drains are available, but the advice I need really is which option to choose or how to go about the job.

I can't re lay the existing slabs to achieve the level of the existing gully because they would have to be lifted quite a lot and over a large area (unless I build a step). Also they would be higher than a subfloor airbrick I have at the back then as well (which is another reason I can't just fill in the area with a step, as I'd be blocking the airbrick).

If I go the acco drain route I will have to channel out a lot of material, possibly fit a sub ground pipe too and the only place I can then send this water is onto the grass which might lead to flooding there.

 

[Ivor Windybottom]

Would you like me to design the whole thing for you? I'll pop round and take all the measurements this aft.

Seriously though, gravity goes downwards. Design something that doesn't rely on it going uphill and all should be well. Breaking out and replacing that old gully wouldn't be a big deal, if that's a good way of doing it.

But I wouldn't want to put surface water into a sewer, especially not when you have lower land elsewhere. It may just need re-paving with a controlled gradient directing the water to where you want it, no need for pipes at all.

 

[danlightbulb]

Would you like me to design the whole thing for you? I'll pop round and take all the measurements this aft.

Seriously though, gravity goes downwards. Design something that doesn't rely on it going uphill and all should be well. Breaking out and replacing that old gully wouldn't be a big deal, if that's a good way of doing it.

But I wouldn't want to put surface water into a sewer, especially not when you have lower land elsewhere. It may just need re-paving with a controlled gradient directing the water to where you want it, no need for pipes at all.

Ok understood.

Can I just ask a couple of clarification questions then please.

The area in question is round a corner of an outhouse and is only narrow. If I slope a slab or concrete away from the house (which obviously I want to do) it would be sloping towards the outhouse. Does this matter?

Perhaps I could try angling the slab/concrete away from the house and at the same time away from the outhouse but this would direct water exactly to the step outside the back door. Likely to mean icy area in winter?

Or do I definitely need aco drains along the side of the outhouse to try and carry the water away. The issue is there isn't much of a slope so I'm digging out to fit the aco drain then there is nowhere for the water to get out of the aco drain unless I dig a deeper channel at one end and connect some actual pipe to it.

Finally at the moment the paving is a mismash of block paving and concrete slabs all laid on top of an old concrete patio slab. I could try and pave the area nicely or I could just try and form a concrete pad with the required slope. Any thoughts on this?

 

[Ivor Windybottom]

My suggestion...

You'll know better whether this would be possible. 45 degree cuts are commonly used on paving.

Add a bit of tip away from the wall to get it out from behind the step.

 

[Ivor Windybottom]

Oh, is that your neighbour's house or boundary? If your houses are that close then you definitely need something more complicated.

 

[danlightbulb]

It's the neighbour house. We share a side access 1m wide. All the guttering downpipes, kitchen wastes and bathroom wastes go into a shared drain/sewer running down the centre of this access.

The neighbours house is slightly higher than mine so there is a step up into their back gate. So I can't send water that way.

I'll post some more photos later but basically the downwards direction is down the alleyway, a right turn into my garden to my back gate then a left turn down my patio in front of my back door.

 

[Ivor Windybottom]

I'm sure you can work it out. 45 degree cuts are useful in confined corners. But acco drains are a good option, better to drain into the lower land via a soakaway. You shouldn't really be putting potentially muddy surface water down the drain.

 

[Ivor Windybottom]

Also have a walk around when it's next raining heavily. If a 1m wide strip of ground is getting unusually wet then it's likely that there's something wrong with the gutters, downpipes and drains. Check everything, including what happens at (and below) ground level.

I had a similar scenario at our last place, with a damp underfloor. I buggered about with all kinds of stuff on our side, spent days and £1000s fitting drains, then saw that the neighbour's downpipe just spewed into the soil, there wasn't even a gully. They grumpily fixed it after I complained, protesting that I was talking rubbish, all our damp issues went away months after.

 

[danlightbulb]

I'm sure you can work it out. 45 degree cuts are useful in confined corners. But acco drains are a good option, better to drain into the lower land via a soakaway. You shouldn't really be putting potentially muddy surface water down the drain.

Are you saying 45 degree cuts in a paving slab in order to get a fall in two directions?

I'm not sure whether to put paving slabs there or just lay a concrete pad. Then I can shape the pad to fall in the direction I want.

I do have some dripping guttering up at the roof too. Problem is I can't get up there, due to the access being only 1m wide it's no good for ladders, would need scaffold.

I've had quotes to get roofing and guttering work done but all in it's in the region of 5 grand so a lot of money.

 

[Ivor Windybottom]

You need to fix the roof, you're dealing with the symptoms rather than the cause. You can buy or hire some very high scaffold towers, but they need outriggers and you don't have the space for them. Scaffold is probably the only way it can be done, the scaffolders will rest against or anchor to the buildings to give the required stability.

I mean the green 45 degree line I've drawn on your plan. That's how sloping paving is usually resolved where there's a change of direction. Either by sculpting concrete (harder than it looks), or cutting a slab diagonally (easier than it looks if you have a cutter).

Poured concrete could work, but would need to be skilfully laid and you would still need sufficient fall (>1 in 80) available and a design. If you try to wing it then you'll just end up with puddles in different places. The surfacing material doesn't really matter, the design does.

You will need underground drainage due to the houses being so close. But you still can't avoid solving the actual issue, which is fixing the roof.

 

[Ivor Windybottom]

...before your neighbour asks you to pay for the damp issues that they will undoubtedly also be suffering from.

If their roof also needs attention then there should be potential for saving money by sharing the scaffolding.