There is a comprehensive guide at the Bluescope website at http://www.steel.com.au/products/coated-steel/colorbond-steel/basix-and-bca-classification

Pitched roofs are preferable for snowy areas to prevent collapsing but flat roofs are great for rooftop gardens. Though I voted neither it really should be either or both because so much depends on the area and the need.

Thanks for your thoughts, they have helped us with our decision. We're now planning on using the barramundi roof tile (it's a grey, a bit softer than the soho nights black. And not so shiny) with matching gutter and fascia. And the cladding in paperbark. I was thinking cream windows instead of the timber, so there's some lighter colours on the brick downstairs to tie it to the top. We can't match it exactly to the paperbark cladding because we aren't using aluminium windows, but I'm hoping the cream (which is supposed to be more of an off-white with this manufacturer) will look okay in the clad dormers upstairs. Fingers crossed!

As someone who bought a brick house recently, a major reason for the decision was the low maintenance of unpainted brick. So, no, don't paint the brick! The facade above the brick looks heavy and dominating because it is so bright white and all one colour. Why not go for a more retro look, break up the solidity of the overhanging facade by painting the vertical trims a different colour? Pick a colour that compliments the brick and keep in mind that colours were more adventurous in the 70s. Embrace the fun of the beach and the retro look without going overboard. Leave the brick as is, paint window trims to contrast and catch the light., maybe add shutters in the same colour to make windows look bigger and add more to catch the eye under the eaves. And paint the front door a fun, bright colour. Citrus colours catch the light and pop, but check they don't clash with the colour of the brick. You need contrast and brightness. Our blonde brick house was built in 1960. We painted the front door, the awning over our sliding doors and our garage door all the same colour: bright citrus orange (the garage door has 2 horizontal white stripes). The result was an instant uplift. We then had the roof restored and painted a terracotta colour (concrete tiles) and cleaned the eaves. The house looks fresh as a daisy and so much more attractive. The paint cost about $100, and the roof cost $6000. Money well spent! Then we worked on the gardens. We took out tall plants close to the house and replanted the gardens with more attractive flowering plants, going for colour. It all looks much more inviting now.