My shed needs repair. It is 14' x 8', sags in the middle a bit, and some of the frame is rotten around the edges. The window frames are rotted and some floorboards too. The roof and walls are okay. It is on a concrete base, so I don't know why it has sagged. It's about twenty eight years old, and really is too good to replace entirely. Is it worth repairing? Should I get a new one? If I can get someone to repair it, what section do I use in Rated People? There doesn't seem to be anything under shed repair or garden buildings.