Help: Deep-flow gutters

[my_name_is_slim_daisy]

Hi everyone,

Good to be here. After googling around for help with period properties I stumbled upon this forum, and looks like the community is active, friendly and helpful!

I recently purchased an Edwardian house - built around 1925 I believe. I'm trying to get it water tight so have done a fair bit of roof work which I was rather pleased with. Then it rained bucket loads for the first time since I moved in, and I realised the gutters are probably made from Ikea plastic colanders.

I've been advised to get deep-flow gutters as it holds a lot more rain water. I've been doing some research on what the process is to have new gutters installed and I was hoping you might be able to chime in with anything I may have missed. Any advice would be greatly appreciated .

• To measure the "fall" (i.e. decline?) for the gutters, this is the proposed calculation/method: use a fall of: 1mm:800mm. Measure the total length of fascia that needs guttering and divide it by 80. This gives the total fall over that distance. Fix first bracket and run a string line from it but lower at opposite end according to your fall. Fix brackets to fascia at correct spacing so and clip gutter in. Does this sound about right?
• Place a gutter bracket every 800mm.
• Use rust proof screws.
• Do I need to prepare the fascia boards e.g. filling in holes, primer etc?
• Is it sufficient to use a ladder or is it best to hire a mobile platform / scaffolding? I'm happy to use a ladder if it's enough to get good results.
• At what distance should I place each union joint?
• Anything else to consider?

I'm quite tempted to do the work myself, but I have the following three quotes too - what do you think?

• Quote 1: £2,160 + VAT. Replacing gutters and using existing downpipes. Not specified whether they will use a ladder or mobile platform/scaffolding. Lots of good reviews on Which.co.uk and other sites.
• Quote 2: £5,000 + VAT. Replacing gutters and downpipes. Erecting scaffolding to front, side and rear elevations. Good reviews on Which.co.uk and other sites.
• Quote 3 : £1,000 + VAT. Replacing gutters and downpipes. Sounds like they will use ladders to get the job done. Found via recommendation. Decent google reviews.

Very nervous about this as I really want to get this right. I really can't deal with having damp issues from the splashbacks etc. Thanks in advance for your time and advice!

 

[CliffordPope]

I've sometimes thought about the theory of gutter design - it's good that you have found a recommended fall. I have sometimes wondered whether that figure should be adjusted depending on the kind of leaves prevalent in your area - common sense would suggest that pine needles and say sycamore leaves would need a different speed of water flow in order to carry them along the gutter without stopping and blocking. It would also depend upon the angle of the roof.

Another point of course is the position of the gutter in relation to the slates - you don't want the water to overshoot the outer edge, but neither to dribble down the inner. Obviously it can't be optimum at all points along the length because of the fall.

 

[Cubist]

Installation of new guttering, downpipes and other associated rain goods does not require much in the way of expertise, effort or equipment. Barring for the fact that it requires the installer to work at some height and therefore carries some risk, the work involved is far from arduous and the technical challenges are limited to those associated with achieving a consistent 'fall' (as you term it decline) from one side to the other of the house and the making of a few cuts to ensure correct length and good joints between the various components.

I appreciate that in London one can find plumbers that arrive on site in their personal Feraris but.....

Unless your house is a mansion with exceptionally large front and rear elevations I would suggest that one man, his lad, and their ladders and other tools could eat this job easily within a single day for both elevations! In terms of materials costs for a typically sized home I would not expect to see a cost, assuming modern and typical rain-goods, above a £100 for everything that may be needed.

In terms of the prices you have been quoted;

1. The £1k is more than healthy and the profit should pay for a family weekend in Brighton.
2. The £2160 is extortionate and the profit would pay for a family fortnight in Mallorca.
3. The £5160 is criminal and the profit will pay for the guys next couple of weeks in Dubai. (Call the cops)

Frankly, I think you would be barking to consider any of these as being realistic.

 

[fernicarry]

realised the gutters are probably made from Ikea plastic colanders.

You mean they were overflowing? The culprit might be the below ground drainage not allowing water to drain away fast enough rather than the capacity of the gutters. You'd need an awfully large roof area draining into a relatively small number of downpipes to need higher flow than normal. And if you did need it then you'd need the whole system to be high capacity otherwise it will still back up somewhere.

Several of my downpipes didn't drain in any meaningful way but it was only obvious when you got a really heavy downpour. Rest of the time I suppose the rain slowly soaked into the ground. Over the years I've ended up replacing almost all the original clay below ground drainage around the house as it was either broken and leaking or completely clogged up. Start by evaluating that aspect and work upwards.

Related, its good design to have a shoe and a gully at the bottom of the downpipe rather than the pipe just disappearing underground. That lets you assess how well its draining and you can fish the leaves and gunk out of the grating.

My gutters were replaced by a local builder and his labourer off of ladders. That was before I got stuck into doing things myself. If it was today I'd have no issue doing it myself with a trusted mate. You would have to be comfortable with that mode of working since you're going to be moving around somewhat heavy items that will have a lot of leverage over you and the ladder. You'll also want a stand-off so that you can work from further away from the wall than the distance that the roof overhangs by. Check that you can actually get to everywhere you need off of ladders. There are bits of mine that really need two towers with a platform across between them. No idea how the builder did that, probably in a very non-HSE compliant manner...

Definitely take the opportunity to tidy up the fascia boards. But you'd want a guaranteed spell of dry weather to prep and let a couple of coats of paint dry properly. Doesn't need to be a crazy perfect finish, its 20 foot up in the air after all but you do want the fascias to be well protected so that they last and to not have to redo it all again in 3 years time. Too late in the year to start that job up where I am.

When evaluating quotes its useful to break it down into components -- materials, plant hire, labour (ask how many guys and for how long) etc. The difference between this and the quote is the profit and you can judge for yourself whether you want to be giving that away as a present.

There will be a good few hundred in materials whoever does it so a grand for a couple of guys for a couple of days (in London!) sounds alright if it fixes your problem. It might not and just be the start though...

 

[Lacan07]

For 1K plus I'd be expecting them to renew the stuff the gutters are actually attached to.

The trouble with replacing guttering for the DIY'er is its probably a 2 man job.

 

[my_name_is_slim_daisy]

Thank you all so much for your responses

@CliffordPope I hadn’t even thought about leaves and other debris! So many different angles and slippery slopes (pardon the pun). There aren’t really too many trees within a 5-10metre radius. At the back of the garden there are a variety of trees but these are around 15-20metres from the building. Will definitely discuss the fall and optimal angles with the roofer (hopefully I’ll understand what he’s proposing).

@Cubist I’d love to attempt this myself but I realised coming into a period property, there’s so much to do, and since this is a fairly urgent task, I have to bite the bullet and get the roofer in. The roofer assures me it’s not going to pay for a weekend trip to Brighton, but if you all tell me it is then I believe you :-(

@fernicarry yes I went out in the pouring rain to walk around the perimeter of the house, and the gutters are definitely leaking in some areas. The downpipes don’t disappear into the ground so I’ve seen that there’s no issue with water being directed into the drains - will keep an eye on it though.

Good point about the fascia boards - another area I overlooked! Thanks for mentioning this. My roofer said he could see that the paint is peeling but not sure they are rotten. He is proposing to remove any rotten areas and install a cap over fascia so that we would have a "better structure" on the roof, and the new plastic will cover the existing timbers. In all honesty, I haven’t quite absorbed this yet - don’t know how this ensures a better structure?

@Lacan07 , thanks for the contribution - I hadn’t thought of this. The quote doesn’t include renewing anything the gutters will be attached to (*sigh*). I’ll have to talk them into at least renewing it. I think it's definitely something I would look to do myself in the future, but I don't really have a reliable buddy that can help.

So it sounds like I’m better off getting the existing timbers protected (if they’re in good order), and then have the roofer come back to install guttering?

What would you say is a reasonable price to have uPVC fascias and soffits installed on a 3-bed semi (roughly 1,100 sq ft)? If I’m paying for a Brighton trip, I’m determined not to pay for Margate too!

 

[my_name_is_slim_daisy]

Forgot to ask, what is a reasonable price for having just the gutters installed?

 

[Stevers]

The problem with adding a thick plastic fascia is that it reduces the overlap of the tiles into the gutter. The plastic gutter used may also be offset from the fascia. On my parents' house the plain tiles used had very little overlap, and after the fascia and gutter wallies had finished the rain could dribble down behind the gutter.

 

[fernicarry]

don’t know how this ensures a better structure?

Please don't let them do this. Once the woodwork is covered up with plastic it will decay even faster. If the plastic is just attached to the wood then that definitely won't constitute a better structure and it'll all end up in the garden together one day. The builder might try to attach to the joist ends or the sprockets if those are visible but that depends on your roof construction. They aren't on mine, the underside of the overhang (the soffit) is all boxed in.

External woodwork is certainly a pain to maintain but its part of the character of your house. There are various discussions on here on different kinds of paint systems. Contractors won't naturally choose the sort of stuff that we like, they won't even have heard of it, so there's another battle you will have with him if he is going to do the work. My weapon of choice these days is Jotun Demidekk Ultimate. Claims a 12 year maintenance cycle if done right which is about as good as it gets.

Where are the gutters actually leaking? At joins, at the low end of the run? Has all the gunk and rubbish been cleaned out of them? There are plenty of trees around here but the biggest offender seems to be little balls of moss that get washed down off the slates. You said you just had roofing work done so if they weren't too tidy they could have left debris in the gutters causing the problem in the first place...

 

[CliffordPope]

We get plenty of the little balls of moss - some of them quite large, on the north-facing side of the roof. They slowly get bigger, and then one day when the weather has been hot and dry they detach and bounce merrily down the roof. I'd estimate that about 75% of them bounce over the gutter, the rest land in the gutter.

They usually then flow along the gutter (science of getting the fall right for the particular kind of debris in your area) but then lodge just behind the connection to the drain pipe. That's my particular grouse about gutter design - the water speed obviously slows as it spreads out around the hole, and that's when it deposits its load. That quickly builds up forming a dam, and backs up along the gutter and there's another overflow.

The design is wrong. The pipe should have a sloping angle of attachment to the gutter, not a sudden 90 degree turn.
Here's a better design:

150mm Half Round Black Coated Galvanised Steel 80mm 'prefab' Gutter Outlet

150mm Half Round Black Coated Galvanised Steel 80mm 'prefab' Gutter Outlet *** WHILE STOCKS LAST ***

www.rainclear.co.uk

 

[Cubist]

Out of all the very good advice above I would put 'Don't let anyone fit plastic/upvc cladding over your timber fascias' at the very top of the list. It adds no structural value at all. Over time it will yellow under sunlight exposure. Any repeated movement due to high winds will cause it to crack and perhaps fall away. It positively adds to any extant rot and can induce more. Guttering and associated rain goods are carried on the fascia boards of the house and, because of wood rot induced by any plastic cladding of the fascia boards, may induce failure of the fixings for these can fail. To echo Fernicarry; Please, please, please Do Not let anyone use that dreadful stuff on your home.

 

[Lacan07]

Out of all the very good advice above I would put 'Don't let anyone fit plastic/upvc cladding over your timber fascias' at the very top of the list. It adds no structural value at all. Over time it will yellow under sunlight exposure. Any repeated movement due to high winds will cause it to crack and perhaps fall away. It positively adds to any extant rot and can induce more. Guttering and associated rain goods are carried on the fascia boards of the house and, because of wood rot induced by any plastic cladding of the fascia boards, may induce failure of the fixings for these can fail. To echo Fernicarry; Please, please, please Do Not let anyone use that dreadful stuff on your home.

Are we talking about just plastic cladding here, whats the score with full uvpc replacement these days? Are they no good?

The whole shebang needs replacing at the back of my house and I'll admit replacement timber fascias weren't high on my list.

 

[stuart45]

If you definitely want plastic, then the thicker boards are normally around 18mm, whereas the capping ones are only 9mm. You can get up to 25mm.

 

[Cubist]

Are we talking about just plastic cladding here, whats the score with full uvpc replacement these days? Are they no good?

Sorry Lacan, it looks like my personal aversion to most things plastic has led to a more sweeping generalisation than I'd intended.

My very limited knowledge of this kind of cladding system is the very flimsy, sub 2mm thick, stuff that became popular a few years back which is simply fixed in place directly over timber boards - in fact its little more than a coating. A few moments research, courtesy of Google, informs me that things have moved on and some of these cladding systems are now much more sophisticated and substantial that are capable of replacing traditional timber boards. However, whilst I would accept that some of these may now be capable of tolerating heavy weather conditions and surviving some heavy physical abuse I would still be suspicious of the devices and fixings used to construct and apply large expanses of such material to a building.

 

[stuart45]

The fixings are 65mm stainless steel ring shank pins. You have to make sure you don't bend one when you knock them in as they're really hard to pull out. Once fixed they seem to hold up well. I put some in along the road from me about 10 years ago and they're still up.

 

[a twig]

We’ve just used the 18mm boards on our extension and frankly - they are great. Lightweight and easy to manoeuvre and cut as necessary, but still solid enough to take a screw for a gutter bracket. One of the areas where modern materials win in my opinion

 

[my_name_is_slim_daisy]

We’ve just used the 18mm boards on our extension and frankly - they are great. Lightweight and easy to manoeuvre and cut as necessary, but still solid enough to take a screw for a gutter bracket. One of the areas where modern materials win in my opinion

Any chance you can share a link to these boards you've used?

I'd prefer to keep the timbers cladding free after learning from some of the comments above, however if I had to go down the cladding route, what mm thickness would I get away with? Judging from @Cubist's response <2mm might be OK? I really don't want to risk introducing dribbles of water down the brickwork because of some cladding.

Alternatively if I avoid the cladding, and there is an area of rotten timber along a wall, would I need to replace the entire timber along the wall, or is it perfectly reasonable to cut out the rotten wood and replace it? I imagine the roofer could cut out the timber between a set of sprockets and attach a new plank? (I may need to re-read some of the comments above - I only learnt today what a sprocket is )

@CliffordPope I will definitely be inspecting the materials used by the roofer for the gutters - the green things you're talking about sound like a pain in the moss!

 

[my_name_is_slim_daisy]

The design is wrong. The pipe should have a sloping angle of attachment to the gutter, not a sudden 90 degree turn.
Here's a better design:

150mm Half Round Black Coated Galvanised Steel 80mm 'prefab' Gutter Outlet

150mm Half Round Black Coated Galvanised Steel 80mm 'prefab' Gutter Outlet *** WHILE STOCKS LAST ***

www.rainclear.co.uk

Have you had these installed - or does anyone else have them? I will ask the roofer if these can be used

 

[a twig]

The boards I was referring to are instead of the timber, not go to on top of.

This stuff was it I think - https://www.jparrboro.co.uk/aquacel-16mm-upvc-fascia-board-5mtr-length-white-c2x26038945

 

[stuart45]

Any chance you can share a link to these boards you've used?

I'd prefer to keep the timbers cladding free after learning from some of the comments above, however if I had to go down the cladding route, what mm thickness would I get away with? Judging from @Cubist's response <2mm might be OK? I really don't want to risk introducing dribbles of water down the brickwork because of some cladding.

I've never seen it as thin as 2mm. The capping to overclad the fascia are normally 9mm. It does move the gutter out a bit from the eaves tiles.