Cost of converting brick garage to granny flat

Hello all,

I have been reading with interest the commentary about the new granny flat laws in NSW.

I am in process of buying a house in the Canterbury council area, Sydney. It is on 630m2 and reading through the new granny flat planning laws (or whatever they are called, links were put up on other threads here) it would appear the 50m2 brick double garage in my backyard could be converted to a granny flat under this system.

Has anyone used these new planning laws? I see the council charges $200 odd for an application fee but it is vague on what other requirements there are re surveys and the like for a complying development.

Also any ideas on the construction costs involved in converting a cement floored, brick veneer double garage into a liveable granny flat? Anyone done something similar?

The set up would lend itself to this as a pathway up the side of my house could be used as a private entrance and a carport in front of the garage as a private courtyard/BBQ area (even has a BBQ built there already). There is also another garage at the front of my house so I wouldn't lose a garage for my own car.

Any comments or ideas welcomed.

Milo
 
Also any ideas on the construction costs involved in converting a cement floored, brick veneer double garage into a liveable granny flat? Anyone done something similar?

Milo, your question is like asking "How much does it cost to build a house?"

But realistically if you do the project management yourself and just organise the tradies - around $25-30K in my estimation to do a reasonable job.

If this number is still within the realms of possibility for you, then go get some quotes and jot down some ideas & finishes you want (try to keep it within the same quality of the house, for later resale if you ever do) and go from there.
 
I appreciate my question is a bit vague but have to start somewhere. Thanks for the ballpark figure, that gives me something to go on. And yes, that would be doable for me so looks like I have some work cut out thinking about the best way to do it and getting some quotes.

Thanks for the reply.
 
You're welcome Milo.

Perhaps you could post some before, during & after pics as well as costs along the way - just for the interest of others considering the same thing? :)
 
Hey Milo, it would be prudent to check with the planners at council. I still haven't received an answer to my q's as they are apparrantly still determining the rammifications of the new legislation themselves. SO obviously there are some grey areas - what's new!

Your council may have a clearer picture since you are in a city area with probably more enquiry from the public over this legislation.

Let us know how you go. :)
 
Cheers Rockstar, but I am buying the house regardless, so this would just be a bonus.

But from reading through the pdf brochure and browsing through the legislation itself, I am not sure the council even gets to be involved. If it complies to the legislation you can get a private certifier to issue a certificate in place of DA application and while you tell the council they don't get to rule on it.

I may be reading it wrong of course and I am no a builder or a lawyer so perhaps I am being overly optimistic. I will give the council a ring tomorrow and see what they can tell me anyway.
 
we currently have a large 4 car garage (a "big" 4 car garage) that already has plumbing (toilet and vanity) and 3-phase electricity so were thinking of converting half of it to a granny flat if required for the olds.

unfortunately, even tho the garage is separate from the house, it won't have separate entrance from the street and no parking, so not really useful for tenants.
 
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we currently have a large 4 car garage (a "big" 4 car garage) that already has plumbing (toilet and vanity) and 3-phase electricity so were thinking of converting it to a granny flat if required for the olds.

Is it under 60sqm Lizzie? Double garages are around 36sqm so a 4X may be too large to pass the requirement.
 
The granny flat would still have to pass council planning rules, wouldn't it?
Things such as side/rear boundary setbacks.

I was looking into converting my 4 car garage into a 60 sqm granny flat, but it doesn't meet the boundary setback rules, so this new faster complying development proceedure won't help me.
 
The granny flat would still have to pass council planning rules, wouldn't it?
Things such as side/rear boundary setbacks.

I was looking into converting my 4 car garage into a 60 sqm granny flat, but it doesn't meet the boundary setback rules, so this new faster complying development proceedure won't help me.

I'm pretty advanced in my convo with the Council and Dept of Planning and I may well be first cab off teh rank with this. Will advise if I'm successful. Will draw up plans by week's end then lodge via Private Certifier.

As for cost, I too am shooting for $25K-$30 for conversion of a 56 sqm garage managing tradies myself.
 
The granny flat would still have to pass council planning rules, wouldn't it?
Things such as side/rear boundary setbacks.

Yes. My understanding is that it still needs to comply with normal planning setbacks. You would need to apply for a variation otherwise.
 
Made a call to the town planners at the council. Looks like I have hit a hurdle, which Blackspider has already mentioned. I don't think there is a 900mm setback from the fence line at the side. The council informed me (and makes sense) under the private certification route, you must comply with all criteria. Hence if you don't meet one, there are no variations available, you can not get a certificate.

That would require you to go the DA route. The council said they doubt they would allow a variation on the side setback (the neighbours house close on this boundary) if I put in a DA.

So looks like I won't go the granny flat route unless the setback is greater then 900. I am not sure of the exact distance, have to go back and measure it or look at surveyors drawings. Not hopeful though.
 
Has anybody made enquires about getting an existing unapproved granny flat certified under the new rules?

I am trying to obtain more exact detail on the rules to be sure my g/flat will pass the test before I identify myself as someone who owns an unapproved structure :D
 
Has anybody made enquires about getting an existing unapproved granny flat certified under the new rules?

I am trying to obtain more exact detail on the rules to be sure my g/flat will pass the test before I identify myself as someone who owns an unapproved structure :D

Yes, I just did one for a client in Blacktown Council just last week.
I was able to convince Council to give him a 'Building Certificate'. Building Certificates cost only $210 and require an 'ID-Survey' from a registered surveyor (cost about $450). This will be 2 pages; one is a statement and the other is a drawn-up plan. The Survey Plan will look basically like a Site Plan and the structure in question will be labeled as 'Secondary Dwelling' on the survey plan. Council then sends a Compliance Officer to make sure the granny flat complies with the Buildng Code of Australia and Council's codes. Then they issue you the approval. If there is an area of non-compliance, they'll let you know what it is and give you time to fix it.


Be aware, you still need to comply with the BCA and Council's general codes (Incl. Drainage) but you wont need a DA and you wont need to have plans drawn up.

With regard to setbacks: If the structure is there NOW and it wont further impose upon solar access and create any extra overshadowing, Council should approve it.
To the guy above who said Canterbury would be unlikely to approve the garage conversion (as a DA/CC) to a granny flat, I dont see why not since the structure is externaly unchanged. Just dont add windows to the side setback and you should be ok to get a DA done.

Pity its not already converted...you could just go for a Building Certificate ^^.

Brazen.
 
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Yes, I just did one for a client in Blacktown Council just last week.
I was able to convince Council to give him a 'Building Certificate'. Building Certificates cost only $210 and require an 'ID-Survey' from a registered surveyor (cost about $450). This will be 2 pages; one is a statement and the other is a drawn-up plan. The Survey Plan will look basically like a Site Plan and the structure in question will be labeled as 'Secondary Dwelling' on the survey plan. Council then sends a Compliance Officer to make sure the granny flat complies with the Buildng Code of Australia and Council's codes. Then they issue you the approval. If there is an area of non-compliance, they'll let you know what it is and give you time to fix it.


Be aware, you still need to comply with the BCA and Council's general codes (Incl. Drainage) but you wont need a DA and you wont need to have plans drawn up.

With regard to setbacks: If the structure is there NOW and it wont further impose upon solar access and create any extra overshadowing, Council should approve it.
To the guy above who said Canterbury would be unlikely to approve the garage conversion (as a DA/CC) to a granny flat, I dont see why not since the structure is externaly unchanged. Just dont add windows to the side setback and you should be ok to get a DA done.

Pity its not already converted...you could just go for a Building Certificate ^^.

Brazen.

Brazen, apart from the building Cert, would Council still require you to submit a DA? I am just thinking the building cert is for retrospective building work, but using the garage as a granny flat is a planning issue and so therefore planning approval is required?
 
Brazen, apart from the building Cert, would Council still require you to submit a DA? I am just thinking the building cert is for retrospective building work, but using the garage as a granny flat is a planning issue and so therefore planning approval is required?

Strictly speaking, yes, planning approval is required if its not an existing use.
 
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