I have designed a couple of flyover roofs and they have their pros and cons. On the plus side they seem to catch any cooling breeze as they are more open, and hot air doesn't get trapped underneath and build up.

On the minus side you need to make sure that there is enough clearance to easily clean the existing gutter from under the flyover roof. In Melbourne the area underneath stays dry for most storms, but when you get wind blown rain then you will get some rain in under the flyover roof, so it won't be as dry as a verandah. The amount of rain that gets in under the roof will depend on the direction of the wind.

It is better to make the flyover roof freestanding, like in this photo of one of my flyoever roofs, rather than penetrate the existing roofing material with supports.

For your two options in your Cairns climate, I would suggest a flyover roof would be a better looking option, and provide a better quality of under-roof space, rather than the step-down option (which may block your views).

Best of luck with your considerations,

Dr Retro

Thanks Dr Retro!! Very helpful advice! I hadn't considered making the Flyover freestanding but will look into that now. How would you suggest we go about putting a flyover roof on three sides of the house? Would it be better to do three separate structures or one?

I usually try and avoid 2m wide outdoor areas as they are too wide for circulation, and too narrow to usefully furnish. I think a single roof would look neater, but there are lots of different options of how this could be designed with the unequal width deck. I would take the cues from your existing roof, and let a cool looking flyover roof dictate the widths of the deck, rather than vice versa and end up with a messy looking roof, with hips at strange angles. This type of roof design is not standard, so I would be looking to engage a local professional who uses some 3D modelling software (such as Sketchup or Revit) to work with you and show you the roof hipping, heights, site lines and design options with different width decks.

Best of luck,

Dr Retro

Thanks Dr Retro, I will look for someone in Cairns or Townsville to help design something!