Whether you need approval from council or not, depends on several factors. Each State has different rules regarding different types of land and the purpose of tiny homes. So, the first thing is to determine where you are going to locate the tiny house.
If it is in ACT, there is no requirement to gain approval for its installation. It is a very favourable area to have a tiny house on wheels! However, ACT has regulations around sewage in tiny homes so check with the council to make sure you comply with these.
For NSW, there are a number of situations that allow for the installation and use of a tiny house without the prior approval of council. These exemptions are outlined in the Local Government (Manufactured Home Estates, Caravan Parks, Camping Grounds and Moveable Dwellings) regulation 2021, Section 77: Installations for which approval not required:
(1) The approval of the council is not required for the installation of the following—
(a) 2 caravans or tents if they are not occupied for—
(i) more than 2 consecutive days, and
(ii) more than 60 days in a 12 month period,
(b) 1 caravan on land occupied by the owner of the caravan in connection with the owner’s dwelling house if the caravan is—
(i) used for habitation only by the owner or members of the owner’s household, and
(ii) maintained in a safe and healthy condition,
(c) a caravan on pastoral or agricultural land if the caravan is merely occupied seasonally by persons employed in pastoral or agricultural operations on the land, or
(d) a moveable dwelling or associated structure on land to accommodate a displaced person if the moveable dwelling or associated structure is—
(i) maintained in a safe and healthy condition, and
(ii) removed within 2 years after it is installed.
If you are building a house, you are able to live in a secondary dwelling or a caravan while you build the main house. See details on the NSW Government website https://www.planning.nsw.gov.au/policy-and-legislation/disaster-and-pandemic-recovery/secondary-dwellings-granny-flats
For those looking to provide some tourism accommodation, the NSW Government now allows up to 6 caravans on farms larger than 15 hectares. Details can be found on the link https://www.planning.nsw.gov.au/sites/default/files/2023-03/agritourism-and-small-scale-agriculture-developmen-information-sheet.pdf
In Victoria, rules and permits around caravans and tiny homes trailers have been lifted within the Mount Alexander Shire due to an increase in homelessness. As long as there is a permanent dwelling, a tiny home is allowed on a property for an indefinite time period, being similar to NSW in its regulations.
If you are looking to install a tiny home in other States and Territories, best checking with your local council for specific rules in your area. As all other States have varied rules from place to place. Remember, Designer Eco Tiny Homes build tiny homes on wheels so be sure to ask your local council about rules and exemptions around moveable dwellings.