Wonderful!

Looking great, although bedrooms need to fit a desk and at least a king size single or double bed. I would turn the area outside to the right as the private open space for the unit and fence it off. Consider how it will be accessed. Also do a furniture layout for whole unit and consider where a tv will be mounted. All of this will help with window placements. I assume the sliding doors will be the front door. You may need another means of escape too.

This is the granny flat design inspo.

Thank you @kate. Would you mind indicating on the floor plan where to fence off? Will look at bedroom configurations again. In Perth we can have 70m2 internal floor excluding store rooms and alrescos etc

thank you @dreamer

Given that this is the compass reading for our site...any final consideration for window sizes, placements and shading. This is photo of our western boundary fence.

A very good design IMO , in fact 1 idea I might steal in my new place haha . I had a small combined shower and WC off one room -- sort of a mini en-suite . The plan is shower to left and WC to the right and basin straight ahead -- I suspect I can fit the WC straight ahead and have the 200mm wide basin to the right , and then fit a linen cupboard beside it with its own door off the bedroom haha .

Just on a practical level , especially if renting it out -- is that a washer and drier in the bathroom ?

Is there a seperate pathway ?

Is there decent and safe carparking on the street ?

These are probably less critical for your parents , but a tenant doesn't want to be in your face , and also doesn't want to feel spied on or judged .

Red shows where windows, in my opinion should be.
I would not put any windows on the west wall of the granny flat.
This is because of privacy issues, noise, and hot sun.

Great job!

Fences marked on plan to secure private open space. Need a door onto space and gate. Really important if renting it out and need clothesline maybe behind store. Whilst the inspiration pic looks great remember this is your south side so don’t add verandah roof.

thanks @kate. So no verandah? Will that block too much sunlight? Less of a verandah like photo attached? or none at all?

We also get beautiful sea beeezes in Perth called the "Freo Doctor". How do I ensure good cross ventilation for granny flat plan as well as existing main home? Not sure i have the room to include two adjacent windows in each room to move warm air through?

The Freo doctor comes from the south/southwest. The sliding living doors should get some of this breeze.
Open up the bedroom windows and it will go through the granny flat.

Regarding the Freo doctor to get into your main house. Just open up all your windows and doors, in the bedrooms and back living area. There is no direct way the breeze can get through your home.

It will be interesting to know where the washing line for the main house is going? Your granny flat residents, may have full view of your smalls.

Shown in red is where I would do fencing between main house and granny flat.
The main house needs I private drying court for washing, and access to back yard.
When your parents move in, then at that stage a gate can be installed around the laundry area, for them to access into your home and kitchen area.
The living area wall in granny flat may need to be increased on the south corner.

Sorry, I forgot to say that the granny flat will form the boundary fence and we will continue the brick wall to back boundary and past our house. The brick wall will have an entry gate to our laundry door. The overhang for our verandah measures 2.11m currently. @kate suggested to take verandah off for southern sun. Is this because it will block natural light from coming in Kate? And just to check...shall we invest in double glazing for the front of our granny flat , glass slider, or don't bother?

Need cover over door, so may need to compromise at 1m I’d trim back the verandah here and add it to the side so you can sit in the morning sun at least,

Hmm, ran into a slight problem. Need to be 1500mm clear from the back boundary fence in order to put a window in each bedroom. Hubby saying velux skylight in bedrooms to get around this. I think, no, don't bedrooms need windows? If we move forward we lose front verandah width.

@kate, I proposed your eastern verandah increasing depth solution but apparently it would throw off the design aesthetic? Apparently we are trying to get the roof lines as.in inspo pic. Do you think landscaping a nice private courtyard will be OK @kate?

Do you think our living room will need velux skylights?Or will there will enough light coming through? @kate suggested to reduce southern verandah (entry) but apparently it will interrupt the roof lines.

The living areas will get the direct sun from dawn to around 12 noon. No need for skylights.
The bedrooms do not require direct sunlight.
And now.....
Wow, what an oversight with the bedroom windows. That is why there are no windows drawn on the architects plan.....
These things are conversations you should have with your architect.
And I'm still wondering where the washing line is going for the main house.

And if you can't have windows in the bedrooms, where would the fresh air come from. Would the velux skylights be the ones that you can open? But you can't open them when it's raining. Therefore you can't get fresh air into the bedrooms when it's raining????

If you move the whole building 500mm forward, then your front corner will be too close to the boundary on the east side.....

Yes, definitely a conversation with architect is required.

Can you have windows on north side if they above eye height? To prevent overlooking?

Courtyard to have a paved area for a small table and chairs at least

ok, just got email back from architect. ..Thank God he miscommunicated. We can have two windows on the north side boundary of bedrooms!!!!!!! wowserssss. That would've been a complete design change required. Do you think we should go with highlights or larger? what are your thoughts?

@dreamer washing line alongside brick wall behind kitchen. We will have a 3m narrow one to fit the space

Since the bedrooms are smallish. I would suggest a window starting at 1100mm from floor. Assuming your doing 30 course ceiling. Do a window about 1400mm high.
This would give wall space under the window for a desk, or bedhead. And still allows sufficient light into space.

@dreamer it will be completely hidden by the brick wall. No smalls on view 🤗

Sorry to be petty, but 1000mm wide passage for a retractable washing line, which is probably around 500mm wide, is tight. Not the most practical size area for hanging out the washing. But I'm sure you have tested the space, so it must be okay for you.

@dreamer Rake kitchen living and dining. 28c bedrooms and bathroom. ...washing line is a problem. Such a tight space but can't think of anywhere else, can you? This is why I love Houzzers who point out the practical!

Ok, so another conversation, different info. Architect said need to be 1657mm minimum off floor for bedroom windows. We have opted for 31 course. So will do as big as we can? Also do we include some type of awning for the Northern bedroom windows?

@dreamer.....possible solution to your point re washing line. What do you think of fore going washing line in walkway to the planned storage nook behind brick wall of BBQ? This space would measure 900mm x 3000mm. Thoughts?

Regarding washing line. If you put the line where your storage is, where will you put your storage?
I would put a retractable clothes line in the area as circled.
You could still have your line outside the laundry for emergencies, but the line for sheets and normal washing can be in this area. With a retractable line. It can be retracted when you have visitors.
You have not shown where the pool fencing or pool pump will go. So this may not be ideal to your plans.
I just feel you're planing some grand multi living property, but forgetting about the every day things. You have 32 course and 35 course ceilings, but no where to comfortably hang your washing.....

Regarding awning on the north windows of granny flat.
This is a wait and see situation.
You have enough to worry about. If once built and the windows need some form of covering, then install it then.

don't forget your washing line needs to be where there is ample sun, not just where it fits... So to the north or east is good, or for me being too lazy to get up early, west/north. I stayed with someone in a shiny new house and they had a clothesline on the south side! they ended up setting up racks in the living room because it had a window that faced north! I'm not sure if I missed you saying which way is north? forgive me. It also needs to be easily accessed from your laundry room. And IMO those fold out on the wall drying rack things are not sufficient a long line or rotary is better.
A thought on the granny flat.... the loo. It has no ventilation, which I think isn't great in a small house. Can you get rid of the powder room and have the loo in the bathroom making it a bigger space? I would swap the shower and toilet then and have a little window above the loo for ventilation. surely its easier (and cheaper?) to plum the loo when its on an external wall? You'll need a clothesline for the granny flat too? Is the laundry area in the bathroom for the flat?

@fianou luca thank you for your feedback. Presently we haveba rotary line...love it! unfortunately though we have limited options. The spot where I'm moving it, @dreamer may give me feedback on the new location, is facing north east. We also are getting a dryer in our laundry and we have space for a clothes horse. Regards to toilet, my husband is a plumber and does not like toilets in the open. :/

@dreamer, I completely hear you. 🙃🙃 I have kept the storage and moved washing line to be retractable and in location you suggested. 👍👍 It will be open breezy, sunshine grassed area. Quick drying. I think the reason I have overlooked importance of washing/drying is that for 6 months I have been taking our clothes to laundromat. Its down the road, the commercial machines are awesome. I can get a weeks worth of washing, inc, sheets, towels and plumbing uniforms done washed all at same time in just over and hour (folding a bit extra). Hubby thinks I'm mad, but I love the convenience of it.🤗

With so much of your block being built on, Hard surfaces retain heat which brings to mind

Cat Stevens "Where do the children play"

Some basic changes to the kitchen,laundry, WIP,

Swap the WIP over with the Pantry so that you have external access to the laundry and a WC for outdoor alfresco and pool use. At the moment having the WIP where it is not only blocks access to the laundry and WC for the pool, you have a vision from the Alfresco into the Scullary WIP

The island ,possibly have the drawers,cupboards opening to the sides, still including a 300 situp on the living room end, .Even suggest taking more space from the large Media room. to widen the kitchen for a wider island.

Just some ideas that you may consider, plus look at the access into the Powder room and master, at the moment it looks like you have to head towards the entrance and turn right to go back down the passage way to access these.

Sorry but I feel like you are trying to build a compound, perhaps it would better to go up to save valuable ground space which is import for a family home

I agree with Siri. Also won’t your in laws needs be different than a renter? For example would in laws need 2 full bedrooms versus the type of renters l, who will? If you are building form in laws maybe a flat joined to the main house with a lockable door is preferable and means less loss of outdoor space.