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Do I need to remove moss from my roof?

Does what it says on the tin
Howard
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Re: Do I need to remove moss from my roof?

#360700

Postby Howard » November 27th, 2020, 5:59 pm

Johnspenceuk wrote:
Dod101 wrote:All of this reminds me that my rainwater coming from the roof gutters simply goes into soakaways and not surprisingly, over about the 25 years or so since these were installed, with some of the downpipes, the underground pipe leading to the soakaway is obviously blocked with muck and silt and no amount of rodding seems to work. What is the answer to that? Get it dug up and then cleaned and reinstated?

Dod


Hi
What you should have between the downpipe/drainage & soakaway is a silt trap I found a neighbours under a concrete paving (flag?) slab if you have no silt trap it could be your soakaway has silted up over the years.

John


Your and Dod's post reminded me that one of the reasons I had hedgehogs installed was that around 15 years my porch downpipe used to "back up" and water then overflowed the gutter. (This occurred at first floor level but the porch gutter also took virtually all the rain (plus leaf and moss sludge!) from the front of the house because the upper storey pipe emptied into it.)

I got Dyno -Rod to jet the downpipe toward the soakaway. The operator reckoned it was fairly clear afterwards, but it still didn't take a full water flow in a heavy rainstorm. Once I installed hedgehogs, this must have reduced the the major flow of sludge into the downpipe and I realise the backing up hasn't occurred again despite some major thunderstorms. Contributing to this thread, it has now occurred to me that, with a fairly modern house, it's very possible that the silt trap was being overfilled with rotting leaves and moss and couldn't do its job.

So my suggestion for Dod would be to consider installing something like hedgehogs or similar to see if, over time his soakaway improved. That's a lot less hassle than digging up all the pipework. And another advantage for hedgehogs?

regards

Howard

Howard
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Re: Do I need to remove moss from my roof?

#360702

Postby Howard » November 27th, 2020, 6:03 pm

Dod101 wrote:It is amazing what I do not know but I am inclined to think that power jetting the drain might be a bit drastic itself because I do not know how much pressure it would stand nor do I know what the soakaway consists of. Should I? One soakaway in particular needs attention because it takes a large volume of water as two parts of the roof come together making a big valley down which water cascades with almost any rain. Hand rodding the drain does no good and I guess it must be pretty solid.

Another matter that I should be looking at.

Thanks for the responses.

Dod


See above suggestion. My LF skills don't run to answering two posts at once! Hopefully this may allow the leaves in a silt trap to gradually rot and "disappear" and avoid the need for an excavation.

regards

Howard

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Re: Do I need to remove moss from my roof?

#360820

Postby sg31 » November 28th, 2020, 10:48 am

Soakaways often deteriorate over time and need replacing. Often they are a joke and never worked correctly but people put up with them.

One house I bought had 'soakaways' for rainwater. They didn't work very well but we were renovating the whole property so I left them until we had the structure sorted. When we tried to rod the pipes but we didn't get very far. I asked the labourer to have a dig around. The pipe ended 2metres from the house. They'd dug a trench, laid a bit of pipe in it and called it job done, there was no soakway., just the 2m trench the pipe was in. That property was built in 1920 - 30. It had been like that since the day it was built. All the other 'soakaways' were the same. That was the worst I've ever found.

The house I'm in now was built in the 1960's. Half the roof was drained into the septic tank. Not a good idea. The rest went to 2 soakaways, one was 3 metres from the house, the other was 4 metres away. They consisted of a hole 450mm deep and 450mm square lined with loose laid bricks with a slab over the top. Miniscule for the job they had to do even in free draining soil. This was not free draining soil it was heavy clay. It was fun sorting that out, thankfully I know a local digger driver who owed me a few favours.

Don't make assumptions about soakaways, modern ones are probably ok but anything over 40 years is very likely not doing the job it should. It might pay to have them investigated. Replacing them can be disruptive but it can solve a lot of long term issues.

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Re: Do I need to remove moss from my roof?

#360824

Postby 88V8 » November 28th, 2020, 10:58 am

On our thatched roof, moss builds up on the north side. Periodically, I kill it with Jeyes Fluid.

On the garage tiles a welcome patina of moss and lichen is developing.

I have copper strip on the apex of our sunroom which has a cedar shingle roof. Too early to judge if it will keep the algae at bay.

The hedgehogs, I put in the garage back gutter. Had to secure them with cable ties which is a nuisance for cleaning.
There are a lot of trees round there - I like trees - and eventually the leaf debris composts and begins to block the gutter so it has to be cleared out every few years.
But the downpipes don't block.
Which is good.

V8

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Re: Do I need to remove moss from my roof?

#360832

Postby Dod101 » November 28th, 2020, 11:13 am

sg31 wrote:Soakaways often deteriorate over time and need replacing. Often they are a joke and never worked correctly but people put up with them.

One house I bought had 'soakaways' for rainwater. They didn't work very well but we were renovating the whole property so I left them until we had the structure sorted. When we tried to rod the pipes but we didn't get very far. I asked the labourer to have a dig around. The pipe ended 2metres from the house. They'd dug a trench, laid a bit of pipe in it and called it job done, there was no soakway., just the 2m trench the pipe was in. That property was built in 1920 - 30. It had been like that since the day it was built. All the other 'soakaways' were the same. That was the worst I've ever found.

The house I'm in now was built in the 1960's. Half the roof was drained into the septic tank. Not a good idea. The rest went to 2 soakaways, one was 3 metres from the house, the other was 4 metres away. They consisted of a hole 450mm deep and 450mm square lined with loose laid bricks with a slab over the top. Miniscule for the job they had to do even in free draining soil. This was not free draining soil it was heavy clay. It was fun sorting that out, thankfully I know a local digger driver who owed me a few favours.

Don't make assumptions about soakaways, modern ones are probably ok but anything over 40 years is very likely not doing the job it should. It might pay to have them investigated. Replacing them can be disruptive but it can solve a lot of long term issues.


Thanks for that. My soakaways were built probably around 2000 ish so on the basis you quote should be OK. I know all about my septic tank and the rainwater does not go near there. A problem I have with getting in a digger is lack of access so it may need to be a hand dug job but it sounds as if I ought to get a couple investigated.

Dod

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Re: Do I need to remove moss from my roof?

#360858

Postby genou » November 28th, 2020, 12:16 pm

88V8 wrote:
The hedgehogs, I put in the garage back gutter. Had to secure them with cable ties which is a nuisance for cleaning.

V8


You can get gutter clips - https://www.amazon.co.uk/Hedgehog-Gutte ... 175&sr=1-2

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Re: Do I need to remove moss from my roof?

#360866

Postby AsleepInYorkshire » November 28th, 2020, 1:08 pm

Dod101 wrote:
sg31 wrote:Soakaways often deteriorate over time and need replacing. Often they are a joke and never worked correctly but people put up with them.

One house I bought had 'soakaways' for rainwater. They didn't work very well but we were renovating the whole property so I left them until we had the structure sorted. When we tried to rod the pipes but we didn't get very far. I asked the labourer to have a dig around. The pipe ended 2metres from the house. They'd dug a trench, laid a bit of pipe in it and called it job done, there was no soakway., just the 2m trench the pipe was in. That property was built in 1920 - 30. It had been like that since the day it was built. All the other 'soakaways' were the same. That was the worst I've ever found.

The house I'm in now was built in the 1960's. Half the roof was drained into the septic tank. Not a good idea. The rest went to 2 soakaways, one was 3 metres from the house, the other was 4 metres away. They consisted of a hole 450mm deep and 450mm square lined with loose laid bricks with a slab over the top. Miniscule for the job they had to do even in free draining soil. This was not free draining soil it was heavy clay. It was fun sorting that out, thankfully I know a local digger driver who owed me a few favours.

Don't make assumptions about soakaways, modern ones are probably ok but anything over 40 years is very likely not doing the job it should. It might pay to have them investigated. Replacing them can be disruptive but it can solve a lot of long term issues.


Thanks for that. My soakaways were built probably around 2000 ish so on the basis you quote should be OK. I know all about my septic tank and the rainwater does not go near there. A problem I have with getting in a digger is lack of access so it may need to be a hand dug job but it sounds as if I ought to get a couple investigated.

Dod

Me ... me ... me ... it's my turn now :lol: I suggested trapped rainwater gullies as a solution as it would avoid huge costs and mega inconvenience. It's highly unlikely that the soakaways are blocked or full of silt. I think it's more likely that the feeder pipe[s] are blocked and I would suggest that will be at the point where they enter the soakaway.

If you elected to fit some form of trapped gulley[s] at that point when the discharge pipework is open it may be possible to jet the blockage and remove it.

AiY

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Re: Do I need to remove moss from my roof?

#360886

Postby Johnspenceuk » November 28th, 2020, 2:57 pm

Me ... me ... me ... it's my turn now :lol: I suggested trapped rainwater gullies as a solution as it would avoid huge costs and mega inconvenience. It's highly unlikely that the soakaways are blocked or full of silt. I think it's more likely that the feeder pipe[s] are blocked and I would suggest that will be at the point where they enter the soakaway.

If you elected to fit some form of trapped gulley[s] at that point when the discharge pipework is open it may be possible to jet the blockage and remove it.

AiY

Hi AiY
The reason I would never use a trap to collect silt is the difficulty cleaning it. A silt trap is the correct solution. In a domestic situation you can buy them or I would generally assemble it with 600x600 concrete slab on the bottom a 450dia chamber riser or risers ( you can build with brick or block but I found inspection chamber risers best) with a 100mm dia inlet and outlet (outlet maybe 12mm higher than the inlet) with frame & cover. The principle is the silt contained in the rainwater will never rise as it flows across the trap and drop to the bottom resting on top of the slab. the volume of silt/sediment held in the silt trap is far greater and removing the cover every 10 years? and clean it out with a trowel I suggest is far easier than jetting the drain. When jetting would you not just drive the silt towards the soakaway?

Regards

John

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Re: Do I need to remove moss from my roof?

#360888

Postby Johnspenceuk » November 28th, 2020, 2:59 pm

Sorry should have said the outlet invert 12mm higher than the inlet invert. just to clarify

John

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Re: Do I need to remove moss from my roof?

#360889

Postby Dod101 » November 28th, 2020, 2:59 pm

Thanks AiY. I think I had better get some advice on this anyway. I do not feel it is a pressing problem until it pours rain then I see it all too well! This is getting all too technical for me but I am not sure that jetting the inlet pipe to the soakaway would work depending of course on the pressure in the jet.

Dod

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Re: Do I need to remove moss from my roof?

#361358

Postby 88V8 » November 30th, 2020, 9:11 am

genou wrote:
88V8 wrote:The hedgehogs, I put in the garage back gutter. Had to secure them with cable ties which is a nuisance for cleaning.

You can get gutter clips - https://www.amazon.co.uk/Hedgehog-Gutte ... 175&sr=1-2

Aha!
Also here https://www.ebay.co.uk/itm/20-x-Hedgeho ... 1438.l2649 a bit cheaper.

Thankyou, didn't know about those.

V8

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Re: Do I need to remove moss from my roof?

#361394

Postby Mike4 » November 30th, 2020, 12:00 pm

DrFfybes wrote:We had hedgehogs in the gutters at work. Every year they would be removed and the gutters cleaned of sludge (and there was a lot), so not sure if that was just a maintenance contract that was unrelated.

On the dormer conversion at home we had those clip in plastic meshes on the top floor. After 5 years I climbed up to clean the soffits and fascias (frmthe flat roof), unclipped them, cleaned the plants out from the sludge, and replaced them. 5 years later I did the same, but left them off as the one on the end had started buzzing in strong wind. On the lower gutters I just go up a small ladder every year and clean the moss out from our very mossy steep roof.

Basically, you need to clean the gutters periodically, no matter what you have in or on them.

What I have done is fit some of the plastic grate over the top of where the downpipes are to stop moss rolling down the roof into them.

Paul


I don't have gutters - thatched roof innit. Yay!

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Re: Do I need to remove moss from my roof?

#361621

Postby vfoolish100 » November 30th, 2020, 10:32 pm

Very interesting thread and timely for me.

I have a lot of moss on my single ridged garage roof and interested to hear that the copper strip/wire works (for some at least) - can i ask what it was you used? I was thinking of using a single core from some mains wire?

Also, the garage has a guttering system that seems to just empty onto a flowerbed at the side of the garage - not sure that's a good idea. Should i be thinking of digging (by hand) a soakaway?

Thanks,
Mark

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Re: Do I need to remove moss from my roof?

#361625

Postby AsleepInYorkshire » November 30th, 2020, 10:40 pm

vfoolish100 wrote:Very interesting thread and timely for me.

I have a lot of moss on my single ridged garage roof and interested to hear that the copper strip/wire works (for some at least) - can i ask what it was you used? I was thinking of using a single core from some mains wire?

Also, the garage has a guttering system that seems to just empty onto a flowerbed at the side of the garage - not sure that's a good idea. Should i be thinking of digging (by hand) a soakaway?

Thanks,
Mark


How old is the garage and what materials are used in the roof construction?

AiY

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Re: Do I need to remove moss from my roof?

#361633

Postby vfoolish100 » November 30th, 2020, 11:14 pm

How old is the garage and what materials are used in the roof construction?


Not really sure how old the garage is, I'd guess around the 1980's (could be earlier), Roof is brown tile with felt underneath.

Cheers,
Mark

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Re: Do I need to remove moss from my roof?

#361635

Postby JohnB » November 30th, 2020, 11:18 pm

My garage roof dripped on to some no-mans land next to a shed for 60 years with no issues. I added some guttering to feed a water-butt, using the water on the garden will be a lot more useful than having a soakaway

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Re: Do I need to remove moss from my roof?

#361642

Postby AJC5001 » November 30th, 2020, 11:40 pm

JohnB wrote: I added some guttering to feed a water-butt, using the water on the garden will be a lot more useful than having a soakaway


But where does the overflow go when the water butt is full?

Adrian

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Re: Do I need to remove moss from my roof?

#361643

Postby AsleepInYorkshire » November 30th, 2020, 11:46 pm

vfoolish100 wrote:
How old is the garage and what materials are used in the roof construction?


Not really sure how old the garage is, I'd guess around the 1980's (could be earlier), Roof is brown tile with felt underneath.

Cheers,
Mark

I don't know a great deal about whether copper wire will work. On the only occasion I've ever seen this it was a copper strip about 5cm wide. I took the liberty of looking for anything that might work and spotted this - I've never seen it before and don't know how effective it is/isn't.

https://www.ebay.co.uk/itm/262741368365

I wouldn't worry too much about a soakaway on your existing garage unless there are some indications of structural failure. I'm not a structural engineer though.

AiY

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Re: Do I need to remove moss from my roof?

#361687

Postby DrFfybes » December 1st, 2020, 9:08 am

Dod101 wrote:It is amazing what I do not know but I am inclined to think that power jetting the drain might be a bit drastic itself because I do not know how much pressure it would stand nor do I know what the soakaway consists of. Should I? One soakaway in particular needs attention because it takes a large volume of water as two parts of the roof come together making a big valley down which water cascades with almost any rain. Hand rodding the drain does no good and I guess it must be pretty solid.

Another matter that I should be looking at.

Thanks for the responses.

Dod


Jetting shouldn't cause a problem - I've had loads of terracotta 4 inch ducts jetted over the last few years and generally the problems have been because they've collapsed and needed replacing anyway (these were under roads so more likely to suffer). The swirling water loosens the nearest end of the blockage (pretty much the opposite of ramming it with a rod!) and draws it back along the pipe. You could just shove the hose down with a small nozzle on set to "max force" but of course then run the risk of a blocked drain with a hose end in it. Sometimes even just getting a hose in there will sort it once you get the end to the blockage.

Regarding chemicals - I hand cleaned my silt traps out last week (both the ones from the sinks and the ones from the roof) and several of the surface water ones contained frogs (which was a little unsettling when I discovered the first one) so back to mechanical means for de-mossing our driveway :(

TOP TIP - if clearing partially blocked gutters/drains etc by hand pour a bucket of warm water down first so at least the stuff you are dragging out isn't freezing cold. If they're completely blocked you can warm your hand up in it instead.

Paul

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Re: Do I need to remove moss from my roof?

#361744

Postby Dod101 » December 1st, 2020, 11:24 am

DrFfybes wrote:
Dod101 wrote:It is amazing what I do not know but I am inclined to think that power jetting the drain might be a bit drastic itself because I do not know how much pressure it would stand nor do I know what the soakaway consists of. Should I? One soakaway in particular needs attention because it takes a large volume of water as two parts of the roof come together making a big valley down which water cascades with almost any rain. Hand rodding the drain does no good and I guess it must be pretty solid.

Another matter that I should be looking at.

Thanks for the responses.

Dod


Jetting shouldn't cause a problem - I've had loads of terracotta 4 inch ducts jetted over the last few years and generally the problems have been because they've collapsed and needed replacing anyway (these were under roads so more likely to suffer). The swirling water loosens the nearest end of the blockage (pretty much the opposite of ramming it with a rod!) and draws it back along the pipe. You could just shove the hose down with a small nozzle on set to "max force" but of course then run the risk of a blocked drain with a hose end in it. Sometimes even just getting a hose in there will sort it once you get the end to the blockage.

Regarding chemicals - I hand cleaned my silt traps out last week (both the ones from the sinks and the ones from the roof) and several of the surface water ones contained frogs (which was a little unsettling when I discovered the first one) so back to mechanical means for de-mossing our driveway :(

TOP TIP - if clearing partially blocked gutters/drains etc by hand pour a bucket of warm water down first so at least the stuff you are dragging out isn't freezing cold. If they're completely blocked you can warm your hand up in it instead.

Paul


All very helpful thank you, especially when it is just above freezing with me at the moment!

Dod


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