Their owners think that they're just ordinary chimneys, letterboxes and driveways but to council bureaucrats, they are irreplaceable state treasures.
Such is their historic and social significance they have been nominated to be preserved forever on the NSW Heritage List alongside buildings such as Sydney Town Hall and the Queen Victoria Building.
Nineteen otherwise ordinary suburban homes in Toongabbie, Epping and Wentworthville have been singled out by Parramatta City Council. Most were built about 40 years ago. The nomination documentation cites special heritage-worthy features including a "metal letterbox stand", "massive brick chimney", "mature palm trees" or "traditional symmetrical form and appearance".
In one case, inspectors praised the way a house "integrates the carport".
The proposal is part of the council's draft local environment plan, a document prepared by all local government areas to guide land use and planning decisions.
Owners of the properties are furious. They have been told the value of their properties will fall by as much as $60,000 if the heritage-listing goes ahead.
Buildings entered on a heritage database cannot be knocked down and a development application must be lodged with council for any changes to the house that could affect its heritage significance.
Pensioner Sylvia DeMeur, who owns one of the houses in Toongabbie, said she was horrified to discover her unpretentious bungalow was being considered for heritage status.
Although her massive brick chimney is said to introduce "verticality into an otherwise horizontal architectural composition", Ms DeMeur believes her Lamonerie Rd property has no historic value.
"If it was built by convicts or 100 years old, that's fair enough, but this is just an ordinary fibro house that the next-door neighbour could have built," she said.
She said her chimney hadn't even been used in the two-and-a-half years she had lived there.
She also said if the listing were successful she would be financially worse off in the future.
Her frustration is shared by Darrell Hooper, whose Wentworthville property was included in the list because of its "original metal letterbox stand and the pebble-impregnated driveway".
Mr Hooper said the idea that his fibro property was deemed worthy of preserving for future generations was crazy. "Why would they want to heritage-list a place that's all asbestos?" he asked. "The beams running through the house are rotting, the windows are rotting but they don't know that because they didn't even come into the house."
Mr Hooper, who has been living at the Doig St address for nine years, said while he realised the importance of protecting significant landmarks such as sandstone buildings and churches, he was afraid of the consequences.
"My plan in the future was to demolish the house but, if they heritage-list it, I won't be able to do anything, not to mention how hard it will be to sell," he said.
It is up to each council whether or not to nominate buildings for heritage listing.
According to the NSW Heritage Office, more than 25,000 heritage items have been identified as having local significance.
Among the more renowned landmarks already listed are Hyde Park, the NSW Art Gallery, Sydney University and St Mary's Cathedral.
While it is common for residences to be listed, the bizarre reasons for these latest inclusions have left property valuers scratching their heads.
Kristian Nguyen, of John Virtue Valuers in Parramatta, said there was a market for heritage-listed properties but the 19 residences flagged were very ordinary.
"The homes don't really have any significance. They were mainly built in the 1960s and '70s and are your typical cottages," he said.
As a result, Mr Nguyen estimated the value of these properties would severely diminish.
But Parramatta City Council is determined to press ahead.
Mayor Paul Barber said the decision to update the area's heritage listing, which was about a decade old, was necessary to provide others in the future with a link to our current way of life.
"It is council's view that, if we fail to preserve our local heritage, our reference to the past will be lost for future generations," he said.
The final version of the local environment plan will be on public exhibition from early next year.