Hi thanks for the reply, not sure about this one interesting concept. It just appeared that the moment I mention "timber" that I need full detail plans engineer certificates surveyors etc etc and comply with the Victorian building act which does not allow any exceptions. I just don't get the argument that they are concerned about "loading" over the easement surely a 100mm concrete slab is heavier than something like the above image. thanks Peter

Of course there are other aspects to consider, but orientation plays a very big part in the comfort of a home. The home I'm living in requires not heating or cooling at any time in the year. The living room has sun streaming through the windows this morning, & it's currently 21C inside. That's on a winter's morning! I'd be looking for a lot more than the bare minimum 5 stars! Why build a new house that only just meet an energy rating that will be unacceptable in only a few years. Many builders will orientate their builds poorly, & have to install expensive extras like double glazing just to reach the minimum standards, adding costs to the build. Reorienting the build costs nothing. Plus you'll save on heating & cooling costs. In the end, you'll be far better off financially, plus you'll be living in a far more comfortable house. You're lucky to have the north facing backyard, only 1 in 4 houses have it. Most blocks have quite narrow frontages, you've been blessed with a wide frontage & are extremely lucky to have that very wide backyard. Is be using it to my advantage & placing all the living areas to the north, along with the parents retreat, & the master of you can manage it. The other bedrooms, & bathrooms could occupy the south side (along with the media room, if you want it dark).

underfloor heating can be installed under some new floating floors and fitted carpets but you'd need to contact the manufacturers of the flooring and heaters to confirm precise conditions to suit your existing timber floor but we have an electric blanket style floor heater that slips underneath an area rug and is excellent for keeping feet warm under a table or desk and just plugs into a wall outlet ...we're very happy with our Coldbuster heaters that can be ordered on line in various sizes but first try some large area rugs for instant insulation that can be removed in hot weather

I would second using tongue and groove flooring instead of slatted verandah timbers. You can still seal them with decking oils to protect them, and opt for a good hardwood timber that will last. Then, I would focus on keeping the rain out of the verandah. So... over extend the eaves a lot. In the tropics eaves go out a lot more and keep the torrential rain off the house walls. If the eaves are already built, they can easily be extended by splinting a longer beam to what's there and encasing it. You could go for the half-wall style verandah railing too. It's common where I live. So you completely clad the bottom half of the verandah, below the rail with vj timber and then you leave the top open, you can add the timber trims and traditional features if you like. That would stop rain blowing in as much too, you could even go so far as to install plantain shutters our simple timber louvres that can be pulled across in a downpour.