You wouldn’t normally think of grease being an roof issue, but in some cases it might be. I found a site which provides useful information about the vent hood cleaning industry for restaurant owners and/or managers. The site educates restaurant owners and managers on the latest developments in the vent hood cleaning industry.

One post stood out on the site. It stated that getting the grease out of your hoods and ductwork is a great first step in preventing grease fires at your restaurant – but there’s another area where grease can collect. The Roof! This caught my eye.

If your vent hood cleaners are neglecting to properly clean your rooftop exhaust fan, grease can quickly overwhelm the fan bowl and spread to the roof. Grease on a roof seems unlikely, but it could be a potential problem.

http://hoodcleaninginfo.com/2011/03/14/roof-cleaninggrease-containment.aspx