I'm guessing the roof appeared a little bouncy when the plumber got up on the roof. New roof battens would be a certainty, and maybe some of the rafters need to be laminated with new ones.
I know you have a budget, but it will be money well spent.
Scott.
A Whirly bird will not solve any moisture problems you have in the house.
They are to vent the roof space. If you put a whirly bird in the roof, it will draw air out of your home, through downlights/exhaust vents.
You will lose your thermal rating, and have higher energy costs for heating...
It's not that, im sure your capable of putting a roof on, but by law you have to be a licensed plumber to put a roof on. It's all about covering your backside these days!
Thats not a very large roof, I'd say between 10k and 14k. Will need new roof battens, new gutters and downpipes, also removal of rubbish, old roof etc. Plus insulation blanket.
You won't be able to put tiles on it, so stick to colorbond.
Scott.
Lizzie is absolutely spot on! You have to kill the mould spores, and oil of clove is one of the only things that do it!
50 mm gap is not good, you need 400mm sub-floor ventilation. Good job of checking the sub floor vents :)