Hi, I'm not a pro, just renovated a few homes. At first glance, I would eliminate the small bedroom - make that space the second living area and have the extension come off that room. Add your large master and ensuite on that side of the house (adjoined to the 3rd bedroom) with lots of north facing windows (maybe a sliding door off master, depending on the view). Then at least your master and ensuite could be filled with light. Otherwise you'll need to do a much more extensive renovation, gutting most of the home to swap around the layout and have the living and kitchen areas north facing. Skylights can do wonders!

It looks like the carport is under the same roofline? Is that right? Is there clearance and room at the front to build another carport?

we need a site plan showing distance of house to all four boundaries as well as size and location of driveways and any additional buildings (water tanks etc) and direction of any views

Yes @bigreader your correct!
Lots of room on that side to do exactly that

@oklouise we are on half an acre, with alot of options for change. The only extra buildings are a large shed. Access to this is on the LH side of house - so extention over that driveway is not an option.

Ok so shed and it’s drive are on the north side so extend a wing along southern boundary. Add some more northern windows.

What view lines do you want to see?

Is the block level?

Nice flat block with bush on 3 sides. RH side is neighbour

the biggest challenge is to connect the old and new without compromising the roof and existing floor levels but do you want to keep a single or double carport/garage with internal access to the house and separate from the big shed

Something like this avoiding major roof changes could even add a modular structure

Add some skylights on east side of roof pitch will add some light to centre of house, avoid the western side, keep that for solar panels

pending more information a wrap around extension stepped down to a concrete slab with an almost almost flat roof could potentially fit under the eaves of the original house to add new family living and master suite with double carport and laundry mudroom with original kitchen used as study MPR but this option would add an extra 115sqm to double the size of the original house and may be more than you need/want

Oooo wow this is an option i hadn’t even thought of - really like it!

If you don’t mind…. What would you do if you were to bring the extension to the front rather than back..

So to the right as you have done - but then forward (off where you’ve put the double carport)?

the reason for adding the extension at the back was to increase northern light into the new family room...using my suggested double carport space for living area would have hot afternoon sun and cold in mornings but i'll attempt some more ideas but tell me if you need/want car space in the extension, how you would use the existing kitchen, location for any proposed alfresco and any other ideas that you would like to be considered?

Also in WA, did a similar reno. Biggest fix for us was chasing natural light, north-facing living is a must if you can swing it. I'd avoid extending forward unless you’re okay with harsh west sun. That wraparound idea is smart, keeps rooflines simple and brings in light without gutting the whole place. Skylights made a huge difference in ours too.