Two quandaries in one topic...

[overlander matt]

Work is progressing up at roof level right now and has thrown up a couple of problems that need solutions in the next couple of weeks while we have the scaffolding. I've included the followings photos for reference:





Problem 1: Rain water drainage.

There are three sections of the roof that require a better drainage design than at present. The front and sides of the roof have lead gulleys that empty to the rear so as to avoid unsightly guttering on the front of the house! The rear of the roof empties into standard cast iron guttering. Previously, water from the side of the roof, drained via a 3" lead pipe that emerges through a wooden cornice into a 4.5" gutter that also took the water from the rear of the roof. A short 2.5" downpipe on the right side of the gutter then dumped this water on the roof below. This seems a bad design because the water from the lead pipe tends to splash the wooden cornice and surrounding brickwork leading to rot and brick damage and I am looking for an alternative... How about a downpipe with a hopper directly below the lead pipe which can accommodate the gutter outlet too? This would then avoid any discharge onto the roofing below.

There is an extra consideration for the drainage - the rainwater from the front of the house is channelled through a box gulley in an attic bedroom where it is then also dumped onto the roof below. This feature although a bit of a novelty has caused a fair bit of damage over the years. We have permission to reroute the water through a plastic pipe and connect to a down pipe at the back of the house. I'm keen to see whether all 3 can be connected to a single downpipe running just below the side and rear gutters and how to make this look tidy. I was thinking about a 4" downpipe running up to a rectangular hopper that would catch the rainwater from the side and rear. As the outlet from the front will be lower and probably off to one side, I wonder whether a branch off the main downpipe would look ok and whether to have another hopper? It doesn't sound quite right to me but am not sure how best to collect three outlets into one downpipe...

Problem 2: Fake/wooden corbel detail.

With the gutter removed, it revealed a section of wooden fascia that looks like the adjacent brickwork corbelling! I'm unsure why anyone would have done this. Presumably the brickwork was damaged at some point and this detail was never restored. The timber is not in great condition but not so bad either that it must be replaced. I have no idea what I should do with this - reinstating the brick detail would be a lot of work.

Any ideas on the above dramas would be much appreciated.

Thanks,

Matt

 

[88v8]

...a downpipe with a hopper directly below the lead pipe which can accommodate the gutter outlet too? This would then avoid any discharge onto the roofing below.

It's surprising how much damage is eventually done by splash. So any change that removes splashing is probably for the better. Your hopper sounds a good idea... provided it won't clog up with leaves or moss, given that it will be out of sight and inaccessible.

I would also be tempted to replace any unseen cast iron with alloy.

..... connected to a single downpipe running just below the side and rear gutters and how to make this look tidy. I was thinking about a 4" downpipe running up to a rectangular hopper that would catch the rainwater from the side and rear. As the outlet from the front will be lower and probably off to one side, I wonder whether a branch off the main downpipe would look ok and whether to have another hopper? It doesn't sound quite right to me but am not sure how best to collect three outlets into one downpipe...

Internal box gutters, mmm, architects do like to hide the inconvenient nuts n bolts of a building.

A hopper as you describe is often a good starting point as it allows the interception of debris that might otherwise block a pipe.

Then, seeking inspiration from the Longbottom catalogue, I see a double rainwater branch A598 and a single branch A592.
Don't seal the joints, otherwise if things clog up you won't know where the blockage is.

I don't know the sideways distances involved, but one could also send water sideways by a downpipe and then a length of gutter at lower level, to avoid a transverse pipe across the wall.

When it's all painted to match other rainwater goods, I think the eye will accept most reasonable arrangements, or even arrangements which are a little unusual. It is after all an old building. However your house has a rather formal entablature which may preclude anything too eccentric.

With the gutter removed, it revealed a section of wooden fascia that looks like the adjacent brickwork corbelling! I'm unsure why anyone would have done this. Presumably the brickwork was damaged at some point and this detail was never restored. The timber is not in great condition but not so bad either that it must be replaced. I have no idea what I should do with this - reinstating the brick detail would be a lot of work.

So this is brick-size chunks of timber? How is it fixed? Is it embedded in the wall? Are you sure it wasn't there from new, to rectify a bricky's error? Or perhaps there was a design change mid-build. Oh for a time machine.
It's sheltered, under the overhang. If it were repainted it would probably last a long time. And if it gets a bit ropey, does it matter...
If replacement were feasible, iroko would be a good choice for unpainted durability and colour. Accoya is an option, but probably too light in colour.

EDIT: Ahh, hang on. I've just realised what that picture is. It's a cornice. You've got a section of wooden cornice. Good grief. Wonder if it was bomb damage.
I see what you mean about the cost of recreating it.
Hmm, other than painting it, don't see what to do. Is it possible to give it some detail weather protection with lead?

I wonder if a boat builder could make a repro in fibreglass? Take more than two weeks, but continuation costs of scaffolding aren't very high.

The unforeseens of old buildings.

Btw, lovely petiolaris. They do like to climb, and can reach 100ft in time so one needs to keep the height in mind. You know how to prune it... removing the old flowered breastwood in late summer. We had one on the front of our previous house for 25 years. Don't let the stems go behind downpipes as they grow fat and may prise the pipe off the wall.
We also have one on the end of a brick outhouse. Superb climber for a north or west facing, and I've also seen them trained as a free-standing bush.

Ivor

 

[overlander matt]

Thanks for your detailed thoughts on this Ivor. I've already pruned the climber quite aggressively as it has been allowed to get a bit out of control and with the various repairs we are carrying out it has been getting in the way. I have a slightly different angle...



I feel that time is getting a bit short for a major repair to the timber corbelling. We've been discussing various options and have decided it is best to retain it but repair it as best we can and paint it to hide in against the surrounding brickwork. With a replacement gutter in front of it, I don't think it will be too unsightly. It is just a board with timber blocks nailed to it. Some of these are a bit rotten so my repair is likely just to replace these. As for why it is there, nobody knows but I would suspect damage to the original brickwork.

I really should have sketched my proposed rainwater drainage plan on top of a photo. I've been on the lookout for other similar arrangements but not come across any other downpipes with branches and hoppers. The design is aimed to prevent further damage to the timber and brickwork. On the front of the house the brickwork and timber cornice has suffered significantly from the lead gulley getting blocked and spilling over the cornicing. This is just going to be one of those features we learn to live with and manage carefully.

Back to the hoppers, I have a choice of sizes for the rectangular hoppers - presumably as long as they are large enough to accommodate the incoming pipework then they should be suitable.

I'll post an update in the next couple of weeks when we get this installed.

Thanks again.

Matt