bentleybonnie

Which is cheaper? Raise home and build under or separate granny flat?

Hi, My postwar property on concrete stumps is not legal living height underneath. The total house is only 94 sq metres. Underneath is 1.9 - 2 metres high and is only used for storage.


I am considering putting a ground level "granny flat" on my property which has space for 2 bedroom, 2 bathroom and a separate room (or nook) for study and lots of storage for study materials, linen etc. small kitchen, living, dining area and a small European laundry. Also to have an alfresco or pergola area. (Also room for a wheelchair just in case this was ever required).


My question : Is it cheaper to raise the current home and build the granny flat underneath OR to have a separate granny flat built at the back of the property?


If I raised the current house, I would probably have to do a small extension to it, because once the back to back car space (for 2 cars) is accounted for, there is only about 55 sqm living space left underneath.


The land space is 607 sqm. Our council allows granny flats to be up to 80sqm without council approval (but it has to be approved by a building certifier). Buildings can only be as high as 9.5 m.


My house is very basic. Two of my new neighbours have removed their postwar homes and have built large new houses, but I don't have the funds to do this.

Comments (6)

  • oklouise
    4 years ago

    what's the purpose of the flat? do you need the extra space...how many bedrooms etc would be in the original house, what would you do with the space under the house? what is the floor area of the existing house and how much of the block would be left over allowing for legal setbacks, original house with improvements, new granny flat, legally required separate private spaces, driveways etc would the cost of extra accommodation be worth all the extra expense and in keeping with values of other properties in the area?...it's only cheaper if you get an affordable result that improves your quality of life and maybe you only need some better use of the existing spaces or eg a ground level MPR and extra bathroom rather than a separate flat

    Creativelychallenged thanked oklouise
  • Creativelychallenged
    Original Author
    4 years ago

    what is an MPR?

  • oklouise
    4 years ago
    last modified: 4 years ago

    "multi purpose room" is a space that can be used for any purpose but often used as a rumpus, guest or hobby room eg we have rooms that have been specifically designed for possible use by disabled grandma but in the meantime the space is used as extra bedroom with ensuite and living area

    Creativelychallenged thanked oklouise
  • Creativelychallenged
    Original Author
    4 years ago

    Hi oklouise, In the shorter term, I was going to live in the granny flat and rent out the main house to people I know or 2-3 international uni students. In the longer term, I would like to have it as a lowset living option for my mum who is in her late 70's. Somewhere, low maintenance, where she can keep her independence (as would I), but has me close by to provide her assistance where required. The original house has 3 bedrooms (the 3rd one is only 3.1 x 2.65m with no built in wardrobe. The back of the property backs onto a council park. The house is set back further from the front than all of the neighbouring properties (greater than 7 metres). The area under the current house would just be used for carparking and storage. The remaining length of my backyard from my back steps is 18.6 metres. I don't think it would necessary add value to my property, but rather provide me with an income as well as options for family or friends that need the accommodation. I hope to keep the house for the long term.

  • oklouise
    4 years ago

    sounds like the ground level granny flat would be much more suitable for purpose and keep save the expense of trying to include a stairwell and extra bathrooms and laundries in the main house as well as losing the downstairs storage and carspace and a granny flast built to complement the original house (old Queenslander?) should be much simpler and more cost effective than raising the roof when you have available space...a site plan showing direction of north, the original house plan (any permanent outbuildings, pools etc) and the distance from the buildings to the fence lines could invite some suggestions for a granny flat and/or extension to suit your purpose and make sure you ask mum what she needs/wants as she may be interested in contributing

    Creativelychallenged thanked oklouise