I live in a block of flats with a concrete tiled, pitched roof.
There's moss on the roof, moss blocking the gutters and moss stuffed
downpipes. Consequently, the pricey range of water butts being
theoretically fed from the downpipes remain empty after the recent
rainy period.

Several remedial options are being considered. What I'm wondering is
how soon the moss problem would return to this current level if the
roof was pressure washed or steam cleaned? In terms of recurring cost
would this be an economical option?
--

Mike

On 28/07/2023 17:32, Mike Halmarack wrote:
> I live in a block of flats with a concrete tiled, pitched roof.
> There's moss on the roof, moss blocking the gutters and moss stuffed
> downpipes. Consequently, the pricey range of water butts being
> theoretically fed from the downpipes remain empty after the recent
> rainy period.
>
> Several remedial options are being considered. What I'm wondering is
> how soon the moss problem would return to this current level if the
> roof was pressure washed or steam cleaned? In terms of recurring cost
> would this be an economical option?

How old is the building ?. Even concrete (?MArley) tiles have a
lifespan of only about 60 years. Pressure washing is generally
a bad idea.

The best way to deter moss is encourage the world to revert to
using coal for heating, cooking and electrical generation :-)
This will deal with moss and also treat black spot on roses !.

A possible localised solution might be to fit a length of copper
wire along the ridge of the building, both sides of the ridge
and wrap bits of lead around the cable at intervals. This will
leach gradually down the roof and might deter the moss.

On Fri, 28 Jul 2023 17:32:43 +0100, Mike Halmarack
<mikehalmarack@gmail.com> wrote:

>I live in a block of flats with a concrete tiled, pitched roof.
>There's moss on the roof, moss blocking the gutters and moss stuffed
>downpipes. Consequently, the pricey range of water butts being
>theoretically fed from the downpipes remain empty after the recent
>rainy period.
>
>Several remedial options are being considered. What I'm wondering is
>how soon the moss problem would return to this current level if the
>roof was pressure washed or steam cleaned? In terms of recurring cost
>would this be an economical option?

A strip of copper wire or tape fastened along the ridge will stop moss
forming. I suggest you get the roof and gutters professionally cleared
first, then have the copper fitted. Crawling around on the roof of a
block of flats covered in moss is not for the amateur DIY guy.

--
Chris

On 28/07/2023 17:32, Mike Halmarack wrote:
> I live in a block of flats with a concrete tiled, pitched roof.
> There's moss on the roof, moss blocking the gutters and moss stuffed
> downpipes. Consequently, the pricey range of water butts being
> theoretically fed from the downpipes remain empty after the recent
> rainy period.
>
> Several remedial options are being considered. What I'm wondering is
> how soon the moss problem would return to this current level if the
> roof was pressure washed or steam cleaned? In terms of recurring cost
> would this be an economical option?

Another option may be to scrape the roof followed by a spray of
Benzalkonium Chloride or bleach to help re-occurrence for a number of years.

https://www.youtube.com/watch?v=gHnyoY3IVR4

https://www.youtube.com/watch?v=2eMFsIkz2TM

https://www.youtube.com/shorts/_kN7luPWZ-A

There are various Youtube videos where it seems to have been done
properly with steam cleaning (pressure washing) but a near neighbour did
a DIY job with a pressure washer on concrete tiles and the results were
rather poor, both cosmetically with surface damage to the tiles and not
actually removing all the moss.

--
mailto : news {at} admac {dot} myzen {dot} co {dot} uk

On 28 Jul 2023 at 19:36:16 BST, "Chris Hogg" <me@privacy.net> wrote:

> On Fri, 28 Jul 2023 17:32:43 +0100, Mike Halmarack
> <mikehalmarack@gmail.com> wrote:
>
>> I live in a block of flats with a concrete tiled, pitched roof.
>> There's moss on the roof, moss blocking the gutters and moss stuffed
>> downpipes. Consequently, the pricey range of water butts being
>> theoretically fed from the downpipes remain empty after the recent
>> rainy period.
>>
>> Several remedial options are being considered. What I'm wondering is
>> how soon the moss problem would return to this current level if the
>> roof was pressure washed or steam cleaned? In terms of recurring cost
>> would this be an economical option?
>
> A strip of copper wire or tape fastened along the ridge will stop moss
> forming. I suggest you get the roof and gutters professionally cleared
> first, then have the copper fitted. Crawling around on the roof of a
> block of flats covered in moss is not for the amateur DIY guy.

We just had our roofs cleaned professionally. The work involved pressure
cleaning and removal of all detritus from the gutters, as well as applying two
coats of anti-moss spray. Also redoing ridge tile pointing, any tile
replacement needed, and verifying that all the roof timbers are sound. Well
worth it.

--
New Socialism consists essentially in being seen to have your heart in the right place whilst your head is in the clouds and your hand is in someone else's pocket.

On Fri, 28 Jul 2023 17:54:25 +0100, Andrew <Andrew97d@btinternet.com>
wrote:

>On 28/07/2023 17:32, Mike Halmarack wrote:
>> I live in a block of flats with a concrete tiled, pitched roof.
>> There's moss on the roof, moss blocking the gutters and moss stuffed
>> downpipes. Consequently, the pricey range of water butts being
>> theoretically fed from the downpipes remain empty after the recent
>> rainy period.
>>
>> Several remedial options are being considered. What I'm wondering is
>> how soon the moss problem would return to this current level if the
>> roof was pressure washed or steam cleaned? In terms of recurring cost
>> would this be an economical option?
>
>How old is the building ?. Even concrete (?MArley) tiles have a
>lifespan of only about 60 years. Pressure washing is generally
>a bad idea.

The buildings are early 70s. Sorry to hear that pressure washing may
not be the answer.

>The best way to deter moss is encourage the world to revert to
>using coal for heating, cooking and electrical generation :-)
>This will deal with moss and also treat black spot on roses !.

Might that be the most expensive option? Great for a vigorous and
divisive argument though.

>A possible localised solution might be to fit a length of copper
>wire along the ridge of the building, both sides of the ridge
>and wrap bits of lead around the cable at intervals. This will
>leach gradually down the roof and might deter the moss.

This might be the best solution, though as the theoretical contents
of the water butts are intended for watering vegetables, I don't know
to what extent copper and lead run off will affect the flavour.
--

Mike

On Fri, 28 Jul 2023 19:36:16 +0100, Chris Hogg <me@privacy.net> wrote:

>On Fri, 28 Jul 2023 17:32:43 +0100, Mike Halmarack
><mikehalmarack@gmail.com> wrote:
>
>>I live in a block of flats with a concrete tiled, pitched roof.
>>There's moss on the roof, moss blocking the gutters and moss stuffed
>>downpipes. Consequently, the pricey range of water butts being
>>theoretically fed from the downpipes remain empty after the recent
>>rainy period.
>>
>>Several remedial options are being considered. What I'm wondering is
>>how soon the moss problem would return to this current level if the
>>roof was pressure washed or steam cleaned? In terms of recurring cost
>>would this be an economical option?
>
>A strip of copper wire or tape fastened along the ridge will stop moss
>forming. I suggest you get the roof and gutters professionally cleared
>first, then have the copper fitted. Crawling around on the roof of a
>block of flats covered in moss is not for the amateur DIY guy.
Certainly not for this amateur DIY guy.
--

Mike

On 28 Jul 2023 20:45:43 GMT, Tim Streater <tim@streater.me.uk> wrote:

>On 28 Jul 2023 at 19:36:16 BST, "Chris Hogg" <me@privacy.net> wrote:
>
>> On Fri, 28 Jul 2023 17:32:43 +0100, Mike Halmarack
>> <mikehalmarack@gmail.com> wrote:
>>
>>> I live in a block of flats with a concrete tiled, pitched roof.
>>> There's moss on the roof, moss blocking the gutters and moss stuffed
>>> downpipes. Consequently, the pricey range of water butts being
>>> theoretically fed from the downpipes remain empty after the recent
>>> rainy period.
>>>
>>> Several remedial options are being considered. What I'm wondering is
>>> how soon the moss problem would return to this current level if the
>>> roof was pressure washed or steam cleaned? In terms of recurring cost
>>> would this be an economical option?
>>
>> A strip of copper wire or tape fastened along the ridge will stop moss
>> forming. I suggest you get the roof and gutters professionally cleared
>> first, then have the copper fitted. Crawling around on the roof of a
>> block of flats covered in moss is not for the amateur DIY guy.
>
>We just had our roofs cleaned professionally. The work involved pressure
>cleaning and removal of all detritus from the gutters, as well as applying two
>coats of anti-moss spray. Also redoing ridge tile pointing, any tile
>replacement needed, and verifying that all the roof timbers are sound. Well
>worth it.

That's a pretty comprehensive approach. I wonder if the kitty would
cover it. If not, maybe finding the best way to keep the gutters and
downpipe clear will be the most popular option with residents.
--

Mike

On Fri, 28 Jul 2023 20:06:03 +0100, alan_m <junk@admac.myzen.co.uk>
wrote:

>On 28/07/2023 17:32, Mike Halmarack wrote:
>> I live in a block of flats with a concrete tiled, pitched roof.
>> There's moss on the roof, moss blocking the gutters and moss stuffed
>> downpipes. Consequently, the pricey range of water butts being
>> theoretically fed from the downpipes remain empty after the recent
>> rainy period.
>>
>> Several remedial options are being considered. What I'm wondering is
>> how soon the moss problem would return to this current level if the
>> roof was pressure washed or steam cleaned? In terms of recurring cost
>> would this be an economical option?
>
>Another option may be to scrape the roof followed by a spray of
>Benzalkonium Chloride or bleach to help re-occurrence for a number of years.
>
>https://www.youtube.com/watch?v=gHnyoY3IVR4
>
>https://www.youtube.com/watch?v=2eMFsIkz2TM
>
>https://www.youtube.com/shorts/_kN7luPWZ-A
>
>There are various Youtube videos where it seems to have been done
>properly with steam cleaning (pressure washing) but a near neighbour did
>a DIY job with a pressure washer on concrete tiles and the results were
>rather poor, both cosmetically with surface damage to the tiles and not
>actually removing all the moss.

Thanks for the advice and vid links. A communal film show might swing
it.
--

Mike

That chemical that people referred me to on here did a very good job on
concrete. Still no sign of it returning after a couple of years, but I have
plenty left at the recommended dilution.
The issue for you would be how to get it to penetrate on a sloping roof,
unless you have a cherry picker or something like that.
Brian

--

--:
This newsgroup posting comes to you directly from...
The Sofa of Brian Gaff...
briang1@blueyonder.co.uk
Blind user, so no pictures please
Note this Signature is meaningless.!
"Mike Halmarack" <mikehalmarack@gmail.com> wrote in message
news:vqq7cip6f1qqas2j34mo9qp7ussvvmh5v6@4ax.com...
>I live in a block of flats with a concrete tiled, pitched roof.
> There's moss on the roof, moss blocking the gutters and moss stuffed
> downpipes. Consequently, the pricey range of water butts being
> theoretically fed from the downpipes remain empty after the recent
> rainy period.
>
> Several remedial options are being considered. What I'm wondering is
> how soon the moss problem would return to this current level if the
> roof was pressure washed or steam cleaned? In terms of recurring cost
> would this be an economical option?
> --
>
> Mike

On 29/07/2023 07:59, Mike Halmarack wrote:

> The buildings are early 70s. Sorry to hear that pressure washing may
> not be the answer.
>

Don't rule it out. The guy in the video links I posted about scraping
the moss also pressure cleans some very delicate roofs using reduced
pressure and hot water/steam. He varies the pressure and uses different
types of nozzles etc. dependant on the job. The kind of control that you
wouldn't have with a domestic pressure washer, and possibly not the
solutions provided by a cowboy gutter cleaner.

> This might be the best solution, though as the theoretical contents
> of the water butts are intended for watering vegetables, I don't know
> to what extent copper and lead run off will affect the flavour.

A biocide treatment of the roof may result in you not being able to use
the roof run-off for a few weeks/months for watering crops. However if
the moss is bad it will quick reappear without a biocide treatment.

--
mailto : news {at} admac {dot} myzen {dot} co {dot} uk

On 29/07/2023 08:05, Mike Halmarack wrote:
> On 28 Jul 2023 20:45:43 GMT, Tim Streater <tim@streater.me.uk> wrote:
>
>> On 28 Jul 2023 at 19:36:16 BST, "Chris Hogg" <me@privacy.net> wrote:
>>
>>> On Fri, 28 Jul 2023 17:32:43 +0100, Mike Halmarack
>>> <mikehalmarack@gmail.com> wrote:
>>>
>>>> I live in a block of flats with a concrete tiled, pitched roof.
>>>> There's moss on the roof, moss blocking the gutters and moss stuffed
>>>> downpipes. Consequently, the pricey range of water butts being
>>>> theoretically fed from the downpipes remain empty after the recent
>>>> rainy period.
>>>>
>>>> Several remedial options are being considered. What I'm wondering is
>>>> how soon the moss problem would return to this current level if the
>>>> roof was pressure washed or steam cleaned? In terms of recurring cost
>>>> would this be an economical option?
>>>
>>> A strip of copper wire or tape fastened along the ridge will stop moss
>>> forming. I suggest you get the roof and gutters professionally cleared
>>> first, then have the copper fitted. Crawling around on the roof of a
>>> block of flats covered in moss is not for the amateur DIY guy.
>>
>> We just had our roofs cleaned professionally. The work involved pressure
>> cleaning and removal of all detritus from the gutters, as well as applying two
>> coats of anti-moss spray. Also redoing ridge tile pointing, any tile
>> replacement needed, and verifying that all the roof timbers are sound. Well
>> worth it.
>
> That's a pretty comprehensive approach. I wonder if the kitty would
> cover it. If not, maybe finding the best way to keep the gutters and
> downpipe clear will be the most popular option with residents.

Your roof is 50 years old. You and your neighbours need to
be aware of the lifespan of concrete roof tiles and start
saving for replacement at some point.

On 28/07/2023 20:06, alan_m wrote:
> On 28/07/2023 17:32, Mike Halmarack wrote:
>> I live in a block of flats with a concrete tiled, pitched roof.
>> There's moss on the roof, moss blocking the gutters and moss stuffed
>> downpipes. Consequently, the pricey range of water butts being
>> theoretically fed from the downpipes remain empty after the recent
>> rainy period.
>>
>> Several remedial options are being considered. What I'm wondering is
>> how soon the moss problem would return to this current level if the
>> roof was pressure washed or steam cleaned?  In terms of recurring cost
>> would this be an economical option?
>
> Another option may be to scrape the roof followed by a spray of
> Benzalkonium Chloride

Just get your neighbours to squirt any unused Timolol eye drops
on the roof every 28 days :-)

On Sun, 30 Jul 2023 11:12:06 +0100, Andrew <Andrew97d@btinternet.com>
wrote:

>On 29/07/2023 08:05, Mike Halmarack wrote:
>> On 28 Jul 2023 20:45:43 GMT, Tim Streater <tim@streater.me.uk> wrote:
>>
>>> On 28 Jul 2023 at 19:36:16 BST, "Chris Hogg" <me@privacy.net> wrote:
>>>
>>>> On Fri, 28 Jul 2023 17:32:43 +0100, Mike Halmarack
>>>> <mikehalmarack@gmail.com> wrote:
>>>>
>>>>> I live in a block of flats with a concrete tiled, pitched roof.
>>>>> There's moss on the roof, moss blocking the gutters and moss stuffed
>>>>> downpipes. Consequently, the pricey range of water butts being
>>>>> theoretically fed from the downpipes remain empty after the recent
>>>>> rainy period.
>>>>>
>>>>> Several remedial options are being considered. What I'm wondering is
>>>>> how soon the moss problem would return to this current level if the
>>>>> roof was pressure washed or steam cleaned? In terms of recurring cost
>>>>> would this be an economical option?
>>>>
>>>> A strip of copper wire or tape fastened along the ridge will stop moss
>>>> forming. I suggest you get the roof and gutters professionally cleared
>>>> first, then have the copper fitted. Crawling around on the roof of a
>>>> block of flats covered in moss is not for the amateur DIY guy.
>>>
>>> We just had our roofs cleaned professionally. The work involved pressure
>>> cleaning and removal of all detritus from the gutters, as well as applying two
>>> coats of anti-moss spray. Also redoing ridge tile pointing, any tile
>>> replacement needed, and verifying that all the roof timbers are sound. Well
>>> worth it.
>>
>> That's a pretty comprehensive approach. I wonder if the kitty would
>> cover it. If not, maybe finding the best way to keep the gutters and
>> downpipe clear will be the most popular option with residents.
>
>Your roof is 50 years old. You and your neighbours need to
>be aware of the lifespan of concrete roof tiles and start
>saving for replacement at some point.

Maybe get some of the fitter pensioners busy with concrete tile moulds
and a cement mixer.
--

Mike