Build granny flat or duplex?

Were they in NSW? Isnt the legal limit 60m2? Who was your builder? What happens if the tenants get injured in your extra shed to make it 90m2? Does your insurance cover it?

It's all legal and covered. They don't live in it. Part of sepp you can attach ancillery structures to a granny flat. Shed, awning, patio etc. It is only the habbitable area that has to be max 60m2. I was just giving you examples of granny flats i have built and what they cost.
So much false in this post...

1: You can barely build a 60m2 shed for 15-20k let alone a fitted out granny flat.

2: You cant just plonk a relocatable home on your block and get it approved as a granny flat.

3: A 120k 3 bed home (19 square?) from metricon would basically be just a shell. You need to double that figure before it is complete.

Agreed - $120k with Metricon won't get you much! We are building with them currently; and I can tell you site costs alone add up.
instead of granny flat option, are there option to leave existing dwelling and build new dwelling attached to existing dwelling and get this approved as dual occ. Say build a single story vila type 120m2 cost around $200k.
requirement such as car space, private open space, storm water would be your biggest concern to go with this option. This option if approved give you option for income, lower entry and if in near future if Blacktown allows strata title dual occ you're likely meet the requirement.

I should explore this option too.

Any links to a consultant/planner active in Blacktown Council area who might be able to take a closer look at the site and suggest practical solutions?

By the way, the property is in Toongabbie.
Toongabbie to my understanding is Holroyd council, not Blacktown Council, even though it's close to Blacktown

Don't know much about Holroyd, but your duplex maybe back on the drawing boards?
Toongabbie to my understanding is Holroyd council, not Blacktown Council, even though it's close to Blacktown

Don't know much about Holroyd, but your duplex maybe back on the drawing boards?

Mine is in Blacktown council for sure.

"Toongabbie is a suburb of Sydney, in the state of New South Wales, Australia. Toongabbie is located 30 kilometres west of the Sydney central business district and is part of the Greater Western Sydney region. Toongabbie is split between the local government areas of the City of Parramatta, the City of Blacktown and the City of Holroyd. The suburb is often locally referred to as "Toonie" and "Toonga Bay"
what a split between 3 council :eek: last thing you want is a leg in blacktown council for this type of development.

my best suggestion for you is to quickly pencil sketch how you would attach a new dwelling to the existing, and presented it to council town planner. At least from there, they might laugh at you or give you some guidance moving forward.

if you block is a less than 12m frontage, i would think access and car space issue.
I've done a few of these dual-occ's for clients (in Blacktown LGA) and here's the problem:

SEPP: No additional parking needed
DCP: Need to provide (on average) 3 more parking spots, with turn-bays and visitor parking, 2 must be covered

Minimum Landscaping
SEPP: Generous landscaping controls
DCP: Not so generous and must be split between the 2x dwellings, often ruining separation/privacy between the 2x dwellings.

Max Size
Whilst it would initially seem that the DCP is more generous,
SEPP: 60 sq m max + can add garage/carport/patio etc to make it 120 sq m or so
DCP: Almost impossible to achieve the same floor space unless the land is >750 sq m

Other DA Costs
DCP: DA Consent Conditions almost always add around $10,000 or more for beaurocratic things like engaging an Engineer 2 to 3 times, Surveyor 2 times, landscape architects, RTA Turn-bay schematics, hydraulic engineers 2x etc. Expensive approvals just ain't fun.

The DCP requirements and 'DA Consent Conditions' can add considerable cost and hassle not to mention delays (it's a DA)

All but 1 client has stated to me that they wished they'd listened to me and done a Granny Flat. Its just that Council treats 'dual occupancy' as a significant development and they hammer you with additional costs - they can be quite considerable.

The SEPP trumps dual-occupancy UNLESS you can subdivide imho.



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