Hi Dave,
Nice to see you're back with us!!
Firstly, I think fibrefresh was joking! Theres nothing wrong with drying a rug on a shed. I've dried them over numerous things before; garden walls & gates, over doors, over other furniture, tarps outside and even over wheelie bins........
Doesnt really matter as long as they're drying off a carpet does it.
Welcome back, glad everythings going well.
All the best,
Jason.