The NSW National Trust says the changes will mean significant buildings may be demolished and ambient streetscapes will change character.

More importantly, the community will be without a way to oppose such developments before they occur.

The Trust’s conservation director Graham Quint said the changes took decision-making away from councils and left civil court action the only course for communities to fight to maintain their heritage.

The organisation will hold a public meeting at the Sydney Masonic Centre on Tuesday to call for an Upper House inquiry into the planning legislation changes and allow more time for community input.

“The changes have major repercussions for all the things we hold near and dear,” he said.

Mr Quint will speak at the meeting, as will Local Government Association president Genia McCaffery and Total Environment Centre director Jeff Angel.

Mr Quint hopes about 1000 people will turn out for the event, which will coincide with the State Budget.

“Under these changes, demolition will be easier,” he told the Mercury.

“And, while (the government) says any buildings on the heritage list won’t be affected, there are a lot of significant places that aren’t on the list.”

But the changes go beyond buildings.

“Even getting away from heritage preservation, the changes will allow major changes to streetscapes,” he said.

“If you bought in a street because there were a lot of trees and beautiful buildings, there’s no guarantee for your investment.

“And if your next door neighbour put up a second storey, you’d only know when you woke up and looked out the window.”

The trust has a long involvement in planning legislation, beginning in 1946 when the first heritage list in Australia was penned.

The organisation lobbied again for planning legislation in 1979 and Mr Quint said these reforms would take NSW “back to the 1940s”.

“(The government) says it’s simplifying the planning process, but it’s really adding another layer,” he said.