Cleaning Roof Algae Stains [Archive] - MyTractorForum.com - The Friendliest Tractor Forum and Best Place for Tractor Information

: Cleaning Roof Algae Stains


Hutch001b
08-09-2005, 02:34 PM
Anyone have any experience cleaning algae streaks off thier asphalt shingle roof? Mine is looking pretty rough and I'd like to clean it. I've been doing a little internet research and have about decided to use about a 4-5% solution of bleach to water, let sit for a half hour, then rinse with water from the garden hose. Any thoughts? Hutch

JDFANATIC
08-09-2005, 03:15 PM
Hutch,

You might want to try out a product called Jo-Max, I had a commercial painter clean and then restain my redwood siding and that was what he used. Just sprayed it on, and let it sit for 30 min's and it was amazing how much it removed.

Cheers

JDFANATIC
JD2210

jdkubotamurray
08-09-2005, 03:38 PM
I have used 100% bleach from the bottle and a 50/50 mix without rinse (wait on nature), both work here for houses under trees which seem to be the worst.

Fusion1970
08-09-2005, 04:19 PM
I cleaned my grandmas roof in Florida awhile back. Dont quote me, but I think we used a mixture of muriatic acid and water. I would verify that before trying it, as it might have been bleach and water. Id feel bad if your shingles started to melt off. LMAO

Either way, I found a common household sprayer, like what youd use for weed control or pesticide, worked great. Pump it up, spray it on, let it set awhile, brush it with a broom, then rinse. I do remember the roof looking great after we were done.

Greg

msmithla
08-09-2005, 05:20 PM
I have always used Calclean, an A/C coil cleaner. (not the kind with acid)

Works to eat algae off of evaporator coils, works great on houses too. :fing32:

chipmaker
08-09-2005, 09:33 PM
I have used 100% bleach from the bottle and a 50/50 mix without rinse (wait on nature), both work here for houses under trees which seem to be the worst.

I'm with jdkubotamurray, with as fast and a heavy of algae growth that we get here it just about takes 100% bleach or chlorox to do the job. LAst year or the year before I actually pressure washed my roof usiing a low pressure nozzle and low throttle stettimng and it came out looking great.....I have about 120 feet of copper strips cut that one day in the not too distant future, when I get a new roof on, will place up on the roof just under the ridge caps coarse of shingles. I have seen other houses with this done on and it works good at eliminating algae growths......I have also used pool chlorine (HTH) with good resuilts, and whenever I drain the hot tub, I use a small HF pump and spray it up on the roof by the patio, and allow it to finish up its usefullness at keeping algae knocked down......We but 20 or more gal containers when it goes on sale here at Winn-Dixie or BIg Lots for $1.00 a gal

Archdean
08-09-2005, 10:30 PM
Copper Sulfate! http://pmep.cce.cornell.edu/profiles/extoxnet/carbaryl-dicrotophos/copper-sulfate-ext.html , is what I believe you are looking for , available at chem supply houses and Rx's , usually sold in crystal form, disolve in a large container (turns H2O blue) and spray on roof with whatever you have handy, nature (w/sunlight) will stop and reverse the alge action!!

RoGT5k
08-09-2005, 10:42 PM
I've cleaned the green off my asphalt roof using a common pump up sprayer (as mentioned by Fusion1970) with 100% bleach. I tried 50/50 mix of bleach and water but it wasn't working well. I sprayed it on, left it to dry, and let mother nature rinse it off when she was ready. I have heard that a strip of zinc coated steel (galvanized flashing) will leach off enough zinc to prevent it from growing.
Roger

DeereBob
08-10-2005, 10:43 AM
Dean's suggestion of copper sulfate is probably a good one since I believe copper compounds are what they coat ship hulls with to keep barnacles from attaching.

jdkubotamurray
08-10-2005, 12:09 PM
Copper Sulfate! http://pmep.cce.cornell.edu/profiles/extoxnet/carbaryl-dicrotophos/copper-sulfate-ext.html , is what I believe you are looking for , available at chem supply houses and Rx's , usually sold in crystal form, disolve in a large container (turns H2O blue) and spray on roof with whatever you have handy, nature (w/sunlight) will stop and reverse the alge action!!
I use copper sufate here for the pond, certainly wiped out my alge this year, a bit expensive, available at TSC and Co-Ops locally.

jdkubotamurray
08-10-2005, 12:11 PM
BTW, Archdean, watch out for those standing pools of water out there!!

Archdean
08-11-2005, 12:03 AM
BTW, Archdean, watch out for those standing pools of water out there!!

I got it and would welcome seeing some about now!! Dry, Dry, Dry!!!

Hutch001b
08-11-2005, 12:42 AM
Thanks guys! Looked at the copper sulfate at TSC today. The only mixing directions on the container were for aquatic use. I may give the bleach a try first. Hutch