Poor Results

[h2o spray]

We sprayed this detached garage roof on 10/11/2016 Our mix was 35% 12.5 SH/ 65%H2O As you can see it still looks terrible and the client is questioning the process used (these are the after 2 weeks pic's). We simply blew off all loose debris with gas blower then sprayed roof with 12v system and let dwell, no rinsing. We have had 2 good rains , unfortunately the temperature has declined but we have had days in low 60's. Is there anything we are able to do to increase our results ? I am confident we are needing to respray, but am questioning myself  as to what process  needs implemented ? The temperatures will be consistently 40-57    Any help with this unsightly situation is greatly appreciated !

 

 

[Roof Cleaning Virginia]

I can't tell from your pics what the problem is.  Is it residual moss?  Still stained?  Or as I suspect, both?  Please clarify.

Edit to add:  temps are irrelevant, other than the process works a little slower during the application itself.  ie dwell time required might be longer.

 

Edited October 27, 2016 by Roof Cleaning Virginia

[Curb Appeal Pros LLC]

Hey so you need to respray for sure. Looking at the picture it still looks green if its green its still living so its not going anywhere. Maybe your mix was bad? Maybe your bleach was not at 12% when you made it a old/bad batch?  I would think 30% would kill it usually it does try 40 like they said above cold temps make it take longer but it will still clean and work. When all of that turns white it means its dead and will go away if its still green keep hitting it!

[JetBlueRacer]

Hey so you need to respray for sure. Looking at the picture it still looks green if its green its still living so its not going anywhere. Maybe your mix was bad? Maybe your bleach was not at 12% when you made it a old/bad batch?  I would think 30% would kill it usually it does try 40 like they said above cold temps make it take longer but it will still clean and work. When all of that turns white it means its dead and will go away if its still green keep hitting it!

The supplier that I know for SH... 16.5%... He was telling me that sometimes you need to use the 50 - 50 mix even for black streaks... He is an employee for that company so I get it if he is simply trying to sell more SH... !!!

[Curb Appeal Pros LLC]

The supplier that I know for SH... 16.5%... He was telling me that sometimes you need to use the 50 - 50 mix even for black streaks... He is an employee for that company so I get it if he is simply trying to sell more SH... !!!

Sometimes you have to do more than 30% I mean keep going up till you get rid of it 50/50 seems high but if thats what it takes to remove it then so be it.. Rinse your butt off so you don't kill anything. You should be able to the black streaks gone by the time you leave if they are brown they will wash off if they are still black they are there to stay and you need to re treat. The lichen dont expect to get all of it off but if it turns white then your ok gently rinse off what you can and the rain will take care of the rest

[Kleen Roofs]

looks like your mix was real weak. It also looks like what I call brown scum on the roof. I think it is some type of algae, but does not show up until you spray the roof. this holds on to the shingles and will not fall off. It needs to be rinsed off.

[h2o spray]

Thank you all to have replied.. I will be reapplying anoter treatment. SH / guarenteed fresh is being delivered in the am. Will post new results . Thanks again !

[Tennessee Soft Wash]

I clean most every roof at 40% using 12.5% SH that is never super fresh (best we can get here). spray it once, let it dwell. spray it again. let it dwell, then look for dark spots and hit those again.  This is what I do almost every time. 

The moss on yours should turn white almost immediately.  If it's still green, then you've definitely got a weak mix or bad bleach. 

 

Edited October 28, 2016 by Tennessee Soft Wash

[PeakOfPerfection]

Was the roof wet when you sprayed it? Wet moss and green algae will shed SH and won't absorb it if they are saturated. 

[h2o spray]

No, the roof was not wet before treatment. Just received the new bleach batch and was tested @ 15%. So will retreat next week and will follow up with pics. Thanks again to all who have replied.

[Roof Cleaning Jacksonville FL 904-304-0810]

Just looks like your mix wasn't close to strong enough. Looks like carpet moss, you need to soak it to the root. All of that stuff should be white when it's dead. 

[Ultimate Roof Cleaning & Pressure Washing]

looks like your mix was real weak. It also looks like what I call brown scum on the roof. I think it is some type of algae, but does not show up until you spray the roof. this holds on to the shingles and will not fall off. It needs to be rinsed off.

What Kleen said " It needs to be rinsed off". With these types of jobs, we spray our mix on, let it dwell then rinse with 3/4" hose, mini firhose nozzle attached to 20gpm booster pump  Works great.