Due for a 5th now, is it...?

I seriously hope you are planning to rent a young back and NOT go climbing up there yourself again this time. Let's see, fifteen divided by 5 is um... gee Alan, a new roofing design concept might be in order, one able to withstand the gale force winds of Nottingham! (A sheltered walkway might be nice too!) Just be careful if consulting an architect remember the ROM...!