Period Drainage

[malcolm]

I know I keep going on about drains, but what are your thoughts on the latest plan?

I had planned to hide the drain in the trench, but the trench is there to keep the walls dry and I don't want any overflow going down there. Also any drain in the trench would be the lowest point of the sewerage system and if a blockage occurred I would much rather it overflowed into the yard.

I'm now thinking about extending the trench behind the drain to keep the wall dry, but thinning it from 200mm to 100mm so I can still get an arm down for maintenance. The gully would be at yard height spaced out from the wall by 200mm.

Another solution might be to accept the wall might get a little damp (it is 250mm below outside ground level) and put a stud wall inside the kitchen with some ventilation, then stick the drain back against the wall with the botches sorted out.

A stack would be the other solution, but I can't see how I could send rainwater in there without effectively having a vent at gutter height which would be too close to the windows.

 

[Penners]

I can't see how I could send rainwater in there without effectively having a vent at gutter height which would be too close to the windows.

Just a thought - you could introduce a trap into the surface water downpipe. Just be sure that it is constructed in such a way as to be easily cleaned out.

 

[malcolm]

There are two drainpipes and an untrapped hopper goung in there and regs suggest any traps will need to be high enough to put them on show.

I wonder whether plan number 32 might be a winner - extend the trench at full width along the wall, put the drains in there at yard height with a bed of concrete at the top, then backfill with pea shingle and include a land drain to the trench.

 

[malcolm]

I think I've got it now. Plan 33 is to put the drain right up against the wall with a drainage geocomposite layer between the infill and the wall with the plastic face outboard, the top covered, and the side venting into the trench.

I didn't know this sort of thing existed - they might be handy for others with localised ground level problems. Hopefully they will be available in lengths under 50m. Otherwise a concrete slab dot and dabbed to the wall might do much the same thing.

 

[malcolm]

Just a report back in case someone else is looking for inspiration in the future. I decided having the drains in the trench would be a bad idea should the drain overflow, and ended up putting them at yard height and building a retaining wall spaced 2 inches from the wall. It's not a long wall so it should be possible to clear out the gap with a stick. I'll run some edging around the drain to direct any overflow into the yard.

A little later and it's just about finished apart from filling in the hole and surfacing. Hopefully this will be the first year in 10 years where I haven't had to rod out drains. If so it will be well worth the effort.

 

[Zebra]

Well done malcolm. That's some very attractive looking drainage you have there.

 

[mattice]

big boys meccano... very very neat indeed! Almost beaut...

 

[Flyfisher]

Good work there Malcolm. Satisfying isn't it? Even though there soon won't be very much to show for all your hard work - I know that feeling!

 

[malcolm]

Thanks everyone. There are lots of other bits of drainage that aren't quite right and it's good to have the confidence to adjust them when I get around to working in the area.

Haven't seen you around on here much lately Zebra. Have you found a life after the project?

I found a previous ground covering under the concrete - cobbles with a red and yellow panment path. The panments look identical to the ones used to support the chimney on both sides of the timber frame so are possibly quite old.

 

[Penners]

A fine job there, Malcolm! Although, on a point of order, your thread is called "Period Drainage" - and that doesn't look very "period"!

Flyfisher says that you won't have anything to show for all your hard work, but I always regard functional drainage as the antithesis of this. You only have a problem if there is something to see!

 

[Flyfisher]

:lol: :lol: :lol:
Very good point!

 

[Zebra]

Haven't seen you around on here much lately Zebra. Have you found a life after the project

Indeed, I'm afraid I've not been on here much lately. The focus has been rather more on Giraffe's plans, and on job prospects. The house is just sort of hanging about being itself, all nice, warm, dry and comfy, and I've even been getting the odd mountain climbed.

 

[TimHardusty]

Apologies for the thread hijack, but where did you/can one get those grilles? I need to dig a trench at the front of ours to let the walls breath (pavement is tarmacked right to the wall, but 18" higher than when the house was built) and that's exactly what I need!!

 

[Zebra]

Aha! I can answer this question, since it was me who recommended it to Malcolm.
It's fibreglass grating. It comes in black, and with its gritty top, it looks really quite OK, better than it sounds. The company will send out free samples.
http://www.fibregrid.com/grp-grating/square-mesh-grating
I made a galvanised metal frame to fit inside my trench, bolting it to the retaining wall, and making legs for the back so I didn't have to bolt it to the house wall. In my case, since the grating was in an area which had public access, using metal would have made it vulnerable to theft.
I paid I think about £280 for the fibreglass, 220mm wide, 10m long. Metal would have been around four times that, and actually, unless you got some really nice looking church grating, would have looked quite industrial.

 

[TimHardusty]

Fantastic - much appreciated

 

[malcolm]

There are some pictures of our grids installed here: http://www.periodproperty.co.uk/forum/viewtopic.php?f=1&t=14273&hilit=fibregrid&start=15 Mine is supported by wobbly poles.

Nice warm and comfy sounds great. Best wishes for your plans. There is probably quite a lot I could be doing here but most seems to depend on being able to use lime outside.

 

[TimHardusty]

Thanks again.

I've had a quick look at the Fibregrid website and I can't see it in narrow strips. Do you just buy large sheets and cut it, or am I missing something?

I like the centre-tube supports, with the brackets: very neat. I want to avoid screwing to the wall of the house, so that and a ledge on the outside for the grid to sit on is perfect. This is on a public pavement (albeit an extremely wide one and no one can actually walk that close to our house due to planters) so I do need it to be strong

 

[malcolm]

They order it in as sheet and then cut it to the width you want. I think it comes in 3m lengths. The strength largely depends on how you support it, but a post every 1m seems fine for pedestrian traffic. In any case it is quite difficult to walk so close to a wall.

 

[Zebra]

They'll supply it cut to whatever you want, within reason. I wanted 10m X 300mm, and they supplied it in 3m lengths.
It's quite easy to cut it yourself with an angle grinder or jigsaw.

 

[TimHardusty]

Thank you all