The north side of our house and garden shed gets practically no sunshine at all and have developed mold. I saw this product and decided to give it a try. I used per instruction on the container, applying it with a simple pump-up sprayer. After 3 days the mold turned gray and lightened up noticeably. Because we get weather from the west, rain doesn't usually hit the north side of the buildings, but in 2 weeks I really haven't noticed much of a change. My final conclusion is I will still have to pressure wash the surface. Works good killing the mold/mildew, but doesn't seem to wash off by itself.
Spray Once is a surprise, it works really well. When I first sprayed Spray Once nothing happened, but as the directions state it works over time. I let it sit for a week and it took my very heavy green off my stringers going to my upper deck. I used 4 oz to a gallon in my sprayer. The real test I'm waiting to do is my roof.I have heavy black algae on my nine year old roof, and I hate the way it looks.my next project will be to spray Spray Once on my roof, can't wait.
Pros: Easy Instructions, Easy to Apply, Easy to Use, Even Application, Good Coverage, Good Protection, High Quality of Material, Looks Great, Modern
I have been successfully using Jonah Spray Once for several...
October 23, 2020
I have been successfully using Jonah Spray Once for several years. I have introduced it to several neighbors as they were surprised by the results I experienced. Use it once and watch the results every time it rains. Quat products deliver results.
I purchased this item with the hopes of removing unwanted...
August 19, 2020
I purchased this item with the hopes of removing unwanted stains on my asphalt tile roof. After 3 repeated washes the changes in the results were little to none. I had no problem with accuracy in regards to the proper mixture (I am a chemist) and good weather conditions. Therefore, I don't think this product fulfills my needs.
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Response from Rust-OleumSupportAugust 20, 2020
Thank you for reaching out! Rust-Oleum Zinsser Jomax Spray Once works over time to remove stubborn exterior stains from mold, mildew and algae. The bleach-free formula works with wind, rain and moisture over time to remove unwanted stains on fences, siding, roofs, concrete & more. - Rust-Oleum Product Support 3
I used the zinsser spray once as the directions said...
June 3, 2020
I used the zinsser spray once as the directions said and it did not take the black roof stains off it is supposed to keep taking it off every time it rains only time and the rain will tell
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Response from Rust-OleumSupportJune 9, 2020
Let’s talk through this! We want to hear more about your experience with Rust-Oleum Zinsser Jomax Spray Once and try to make things right with you. Please feel free to call us at 800-466-7126 to talk about this more and make sure to have the product handy! – Rust-Oleum Product Support 5
I read the reviews prior to purchasing Spray Once for...
April 22, 2019
I read the reviews prior to purchasing Spray Once for wood siding and brick. The directions were followed by spraying and then leaving it and letting the rain work its magic. It was as advertised. There was no sign of the mold after just one rain storm. I would highly recommend this product!