Who has had their roof cleaned?

[BUDFORCE]

I viewed a property where the flat roof above the extended kitchen looked like a badly kept bowling green.

The valuation reports I look at the valuers state flat roofs only have a lifespan of about 10 years anyway, in reality maybe longer and certainly people do leave them longer, but the point is if you have a flat roof the expectation is you will need to replace it every so often.

 

[Peerzy]

The valuation reports I look at the valuers state flat roofs only have a lifespan of about 10 years anyway, in reality maybe longer and certainly people do leave them longer, but the point is if you have a flat roof the expectation is you will need to replace it every so often.

We've just had a flat roof on our new extension and it came with a 15 year warranty and expected life span of 30 years.

The one on our garage is 35 years old this year and no signs in leaking or issues.

 

[fastwunz]

Felt flat roofs are generally considered to have a 15 year life span. This is on average - obviously this will differ depending on the prevailing conditions such as environmental exposure - especially to the sun

 

[happy_2008]

Had mine done last year and the guy literally climbed onto the roof and used a brush to sweep all of it off

 

[Simon42]

As I posted above I just brushed to remove the worst as pressure washing would risk pointing to ridges and could damage the now brittle old style roofing felt if the jet went under the tiles. I also avoided walking on the roof as our tiles aren't flat and walking does run the risk of cracking them.

If you leave too much moss then the chemical will kill it but leave an untreated area once is comes off. For me the little that was left plus lichen and similar all died and nothing has returned since so I am expecting to retreat every 3 to 4 years and next time no brushing will be needed.

Professionals need to show fast results so pressure washing and use of sodium hypochlorite versus a longer lasting biocide are often their choice, and a key reason I went the DIY route.

 

[jpaul]

and use of sodium hypochlorite versus a longer lasting biocide are often their choice,

you think biocides give better endurance and impregnate more ? ... although folks have talked about patio magic biocide ,

hypo needs to be applied on a damp surface, no real substitute for some prior rain (so spring) and then works fast/real-time, before opportunity for any rain to wash it prematurely,
bit scary applying it though - recently used 15% diluted at 25% on patio, don't know how I'd do it on a roof.

with biocide what stops it being washed away, before its impregnated.

 

[Bluecube]

I do roof cleaning as one of the services I offer. Briefly I work from scaffolding, scrape the moss off by hand (using poles to reach the furthest points) before spraying the roof with a biocide. Do NOT ever get your roof pressure washed. Hypo is not a nice chemical to be using at any point and will bleach your tiles.

All my customers have been extremely happy with the work I do and the effects of a clean and treatment last many years.

 

[Simon42]

you think biocides give better endurance and impregnate more ? ... although folks have talked about patio magic biocide ,

hypo needs to be applied on a damp surface, no real substitute for some prior rain (so spring) and then works fast/real-time, before opportunity for any rain to wash it prematurely,
bit scary applying it though - recently used 15% diluted at 25% on patio, don't know how I'd do it on a roof.

with biocide what stops it being washed away, before its impregnated.

Just my experience of trying both at my last home on the patio and block paving. I found hypo didn't remove everything that biocides do (albeit very slowly) and green returned to the hypo earlier with or without a sealer. I've read some pros that treat roofs with hypo rinse to avoid damage to membranes/felt.

I didn't expect my roof to last more than 12/18 months given water washing down so often but its still working now heading towards three years. For my block paving and patio I add a sealer a few days after treatment but the roof was just sprayed with biocoide and left. With biocides you can also treat so many other surfaces without fear of bleach damage, but don't buy patio magic as its 5 times more expensive than just buying the core chemical.

 

[Terminal_Boy]

I have the old traditional terracotta tiles on my roof which tend to crumble when they have standing water/moisture sat on them for a while, so I brush the worst off and give it a spray with moss killer.

 

[jpaul]

before spraying the roof with a biocide.

what is the biocide you recommend ?
like simon says, patio magic (dlockers 2nd love) is expensive.

 

[Bluecube]

Patio magic is probably a more public friendly (ie more diluted) version of DDAC or BAC50. You can buy the undiluted versions of these chemicals from a chemical supplier. You dilute them yourself at a ratio of 40:1 usually

 

[Mysterae_]

I do roof cleaning as one of the services I offer. Briefly I work from scaffolding, scrape the moss off by hand (using poles to reach the furthest points) before spraying the roof with a biocide. Do NOT ever get your roof pressure washed. Hypo is not a nice chemical to be using at any point and will bleach your tiles.

All my customers have been extremely happy with the work I do and the effects of a clean and treatment last many years.

What do you think of the prices being mentioned in this thread?

 

[Bluecube]

What do you think of the prices being mentioned in this thread?

Pricing depends on where you live in the country. For me, £350 is very cheap but it may have been a small house considering no scaffolding was used. A very rough ballpark figure would be £1000 for a professional company working on a detached four bedroom house. You'll be looking at two men working solid for a day or equivalent.

At a bare minimum, I'd expect workers to use scaffolding unless they're climbing onto the roof to work which is still a no-no for me. Once you weed out the pressure washing cowboys and the No Fear brigade you should be left with reasonably professional individuals...

 

[Freefaller]

Definitely not worth it IMO.

Agreed. It just gets bad again after a couple of years even with coatings and so on.

However if it's REALLY bad, doing a clean and some maintenance may be with worth it?

 

[Freefaller]

Actually on the topic can you use drain unblocker or caustic soda type of product down gutters?

 

[Bluecube]

Agreed. It just gets bad again after a couple of years even with coatings and so on.

Depends on the environment around the roof but done properly a roof should remain clear of moss for a good three years at the very least. If by coatings, you mean paint, then yes the effect will be limited. Paint is just paint after all.

 

[Freefaller]

Depends on the environment around the roof but done properly a roof should remain clear of moss for a good three years at the very least. If by coatings, you mean paint, then yes the effect will be limited. Paint is just paint after all.

3 years of moss free tiles isn't really worthwhile IMO

 

[Simon42]

3 years of moss free tiles isn't really worthwhile IMO

The issue with moss for me wasn't aesthetics, but that it was tumbling onto our drive, paths and patio and doing a great job of blocking the gutters and soakaways (even with guards the silt from them gets past).

I had to replace one of our soakaways due to this as the previous owners didn't care about the roof and moss. I was quoted many thousands for the soakaway this from several companies but I did it myself as with the roof. Now I spend under £100 every three years and my gutters are clear and the roof spotless.

 

[Freefaller]

The issue with moss for me wasn't aesthetics, but that it was tumbling onto our drive, paths and patio and doing a great job of blocking the gutters and soakaways (even with guards the silt from them gets past).

I had to replace one of our soakaways due to this as the previous owners didn't care about the roof and moss. I was quoted many thousands for the soakaway this from several companies but I did it myself as with the roof. Now I spend under £100 every three years and my gutters are clear and the roof spotless.

Yeah lichen is a pain. When we had our solar panels done I spent a weekend on the roof scraping it all off. Better off protecting your gutters IMO but I'm also lazy!

I suppose if you remove it and then get some gutter protection that might be the best solution?

Unfortunately nature always wins so I've given up fighting her.

 

[Bluecube]

The issue with moss for me wasn't aesthetics, but that it was tumbling onto our drive, paths and patio and doing a great job of blocking the gutters and soakaways (even with guards the silt from them gets past).

This is a very common reason for folks getting their roof cleaned. It’s not so much the roof looking bad but the amount of moss falling to the ground and blocking gutters.

I suppose if you remove it and then get some gutter protection that might be the best solution?

The gutter protectors I mainly see are wire grills over the gutters or hedgehog bristles that sit in the gutters themselves. These are a complete waste of time and money as they trap everything - silt, leaves, moss, dead animals and clog the gutters up even more than if they were just allowed to run freely. The best thing you can if you’ve problem gutters is ensure they actually slope to the downpipe, which they rarely do, and make sure the pipes are clear. All going well, rain will wash away the debris to the downpipe and into the drains