A lenient ACT government has not handed out a single fine for the extended failure to develop, but four of the blocks now have orders in place to encourage compliance.

There were 374 privately owned urban homes burnt in the January 2003 blaze, 435 people were injured, four were killed and 487 homes were destroyed.

Seven homes are yet to be rebuilt, four blocks were still held by the owner from the time of the bushfires.

An Access Canberra spokesman said there had been controlled activity orders issued over four of the blocks - including two blocks held by the owner from the time of the bushfires - to ensure development.

"Those orders are based on a breach of provisions of those leases that require the leaseholder to use the lease for residential purposes," he said.

The spokesman said the separate obligation of a Crown lessee to complete a building on land within 24 months from the lease beginning only applied to the first development on the block, or if a new Crown lease was made over the same property.

A separate ACT Government spokesman said all 26 government-owned homes in urban areas destroyed in the 2003 bushfires had been rebuilt, though some could not be replaced on their original site.

Questions on building work after the fires came as the family who fought a prolonged legal battle to stay in a home on the edge of Kowen Forest, east of Queanbeyan, recently moved out after two decades.

The Crockford family lost their fight about the bushfire risk of the government-owned property they called home for 26 years, their appeal against the ACT Commissioner for Social Housing's eviction order rejected by the ACT Civil and Administrative Tribunal earlier this year.

A 2013 report found, "structures at the premises are not defensible and survival possibility is zero per cent whether the fire is attended or not".

A government spokesman said Housing ACT had now taken vacant possession of the property after working with the former tenants.

The Access Canberra spokesman said the government had