removal of anti graffiti coatings

[bkel]

Hi been a while since I posted on here as things have been coasting along nicely until I came accross my latest job. Part of the work involves removing a permanent anti graffiti coating that was applied to the building, problem is that pressure cleaning alone (hot & cold) won't shift it. The coating seems to be a polyurethane based one but no one knows for sure. It has to be stripped off so the brickwork can be rendered and its the last thing I need to finish. Any ideas on chemicals or products (bare in mind we don't have access to most of the wonderful pre-mix products you all do down here) that would shift this? Any help would be appreciated.