Hi well this one we did from the very beginning designed and drawn by my self .
The aim of this project was to design a quality home using as non toxic building materials as possible while keeping the costs down as much as possible .
We were able to do this by designing the house in such a way as to avoid using the more toxic timber treatments, ie by keeping the roof pitches steeper than ten degrees ment we we didnt have to use h3.1 cca treatment , reasonable eve widths and bevel back weather boards allowed us to use h1.2 external framing and untreated internal frames. The weather boards are untreated larch which is very durable.
For insulation we used natural wool batts through out which rate as high as convention glass wool.
I'd like to also point out that the lower treated timbers are actually cheaper , so its worth thinking about your designs so as to be able to use the lower treated timbers which will meen a more weather tight healthier home ..
We used Macrocarpa extensively throughout the interior for solid t&g floors, stairs , ceiling sarking in bedrooms and all the trim.
Plumbing it costs alot , so i made sure that the bath room ,kitchen and hotwater cylinder were all relatively close together to save on pipe and fittings and time, also it means no delay for the hot water to arrive. We also put in a wet back fire and a solar water heater .