Hi Guys, yes i would like to recommend a method for cleaning conny roofs, i have been in the industry for many years and would of used all the products that have been mentioned on this post, that is of course in the past as i would of found most of them to be caustic and corrosive and as being a green company can no longer use them, and Dave is right i would not use little waffle cloths for this work. we do have a safe product for this application which is non-caustic and non-corrosive and will not cause any damage to surfaces, but in fairness there are many janitorial suppliers in the UK who can supply safe cleaning detergents that are non-caustic, non-corrosive, which you can dip your brush into and clean the conny roofs without having to use harsh cleaning chemicals like TFRs and truck wash detergent i wont mention any other names, but just check out the msds on the products that have been mentioned on this post and you will see that they are all high alkaline based chemicals which are detrimental to conny roofs, its only a suggestion as i said there are many suppliers in the UK who can supply safe and effective solutions for these tasks.