The Roof Cleaning Institute Of America Training & Certification Forum
"Find A Certified Roof Cleaner Directory"

Classicrider wrote:

---

Roof Cleaning Missouri 417-230-8103 wrote:

---

 

swee****erfish wrote:

---

Commercial account called me out to wash this building.  These stains on the synthetic stucco were not a "biological type stain", and traditional SH/ detergent applications did nothing to remove the discoloration. Additionally, this stucco was VERY thin. Even my 3000 PSI machine caused damage in some test areas while not helping to remove the stains at all.

Turns out, after a few hours of head scratching, these stains were patinas cause by poorly installed copper roofing/flashing The giveaway was the green stains on the concrete under the runoff areas.

Oaxalic Acid applied with a pump-up was the winner in the cleaning derby.  It finally removed the stains to an "acceptable" level. Owner realizes these will return unless something is done to the copper roof/flashing.

I'm wondering if a sealer or some other type of application to the copper could help this from reoccurring. Anyone have experience with this type of issue?

Also, for anyone cleaning over synthetic  stucco such as this, be very careful with your SH mixture and Oaxalic Acid. Both  can and WILL bleach out the color in stucco if extra care isn't give towards rinsing. Do not let it dwell too long!

Sorry, no pictures of how the copper roofing cleaned up. I was to busy figuing how to remove these stains!

-- Edited by swee****erfish on Friday 19th of November 2010 07:07:11 PM

---

I noticed there are still a little bit of discoloration after the cleaning, Olaxic is great but sometimes I find Dryvit hard as hell to get completely clean. any one have any thing to add to  this to get it totally clean ?
or should this just be repainted now that its cleaned and  after the flashing is fixed?

Great work Ray

 

 

---

Not sure about what will do a better job but I have always heard a definite NO on painting Dryvit. Part of the reason of installing it is not having to paint it. Once painted... it becomes forever painting. I think it looks really good compared to what you started with!

 

---