After two days of research, and a few rants on Facebook ( thanks tiny Houses Australia) I came to the following conclusions. Seeing as how caravans are very similar I looked at caravan regulations on the road and as well towing other trailers. Before I started wrote down what questions i needed to answer to be satisfied that i was following the law. I assumed nothing so you may have to excuse some questions may seem a little simplistic
Is it legal to tow a tiny house on nsw state roads?
The short answer is yes. I found no restrictions that say that I can’t tow I tiny house. After all there are several vehicles on NSW roads which are bigger than a tiny house. Buses, trucks, most caravans etc are all bigger than a 2.5 tonne tiny house.
Do I need registration
No, in NSW, the trailer including all caravans are covered by the towing vehicle. In other words, the green slip/ registration that you gain for your car towing the house also covers the trailer.
Do I need to attain anything else instead?
In NSW, any vehicles including trailers over 5 years old need a e safety check ( formally called a pink Slip). That is, Provided I buy a new trailer, it will not need to be inspected until 5 years later. Older than 5 years it will need a yearly safety inspection.
How much weight can I tow?
The towing vehicle determines the weight you are allowed to tow. According to the rta
‘ Throughout Australia, the allowable maximum mass for the trailer is either the capacity of the tow vehicle’s towing attachment or the towing limit specified by the vehicle manufacturer for the towing vehicle, whichever is the least’
So your car manual should have information about gross towing mass for your car. If your car manufacturers manual doesn’t have this information the general rule is one and a half times unladen mass.
is there anything else my trailer needs?
Trailers that tow over 750kg GTM Must be fitted with brakes and lights
At least one safety chain ( under 2500kg) two chains must be applied if over 2500kg
Load must not be over 150 mm over trailers width or be more than 2.5m which ever is less
The tow bar should be marked with maximum capacity and manufacturers name and or trademark.
Anything else I would need to know?
lastly a disclaimer, the regulations in this series reflect information current at the time and place specific to myself. If you are considering building your own tiny house, please do your own research and if needed seek professional legal counsel. Use this information as a guide only.
Next stop on this tiny house tour of regulation road: Caravan regulations
Tiny house in oz 
May 20, 2013 at 7:19 pm
Thanks for all your efforts Beth, it is fantastic to see you leading the charge in NSW in your Build. We have already learned a lot from you and I am sure we will continue to do so. Thank you for being such an active part of our community over at http://www.Facebook.com/TinyHousesAustralia and we look forward to meeting you in person one day ! – Regards, Darren