How to Softwash a Zinc Roof
A customer asked us about softwashing a zinc roof
His question was: We have to clean a roof that is clad in sheets made of zinc. We are planning to use Benz Lightning Cleanze and want to know if it's compatible with, and safe to use on, a zinc roof?
We replied: Zinc is one of the materials you need to be very careful with. Like lead it can discolour if you do not protect it by pre and post wetting with fresh water. Zinc can go hazy if not looked after in this manner.
We've never cleaned a zinc roof with Lightning Cleanze, so cannot comment from experience. However, at 10:1 Lightning Cleanze is not classified as corrosive to metal, so should be ok. But it may still tend to slightly oxidise the zinc, so be careful.
As always, first treat a test patch to check that your method works on the zinc roof you intend to softwash.
In general, we recommend using Benz Bio Cleanze ("Biocidal Wash") at 40-50:1.
Apply two treatments to the zinc roof if the colonisation is severe, which will enable the product to soak more deeply into the biological growths than is possible with a single treatment.
After treating the zinc roof with Bio Cleanze, leave it (do not rinse) and allow natural weathering complete the cleaning.
We hope you found this information helpful.
Ben, Leo & Fiona
Also in Benz Trade Tips
Click the link on this page to watch the video ...