Apartment balconies could become ''Hills Hoists on high'' if the state government proceeds with environment-friendly strata regulations to allow residents to hang their washing outside.

The Department of Fair Trading has proposed a change to strata by-laws which prohibit washing from being hung on anything except designated clotheslines without the permission of the owners' corporation - a measure many believe has contributed to high use of greenhouse gas-producing clothes dryers.

Clogged roads have convinced Canada Bay Council to force developers of new high-rise apartment blocks to limit car ownership and provide access to car-share schemes for all residents in the planned high-rise towers.

Households in the new developments will be restricted from owning multiple cars, with rules forbidding developers from providing more than one car space for each unit, even those with three or more bedrooms.

New laws for residential tenancies unanimously agreed by the NSW Parliament today will deliver important protections for tenants and property investors, Fair Trading Minister Virginia Judge said.

People who buy properties off the plan will have greater protection from developers who wish to make last-minute changes to homes such as switching the light fittings or reducing precious floor space.

Property lawyers say new legislation about unfair contract terms could leave some developers exposed to contract terminations if they neglect to review their purchase agreements.