We are at risk of repeating the mistakes made with Ballymun if we do not maintain building restrictions.
The warning comes after a government report found developers cannot make a profit by building affordable apartments and selling them for €320,000.
The report notes that minimising green space and outdoor areas would help bring down construction costs but that this could be unpopular.
Architect Mel Reynolds has said it is not all about profitability.
"If you are looking at a spreadsheet solution to you cutting garden space and cutting balconies and making buildings smaller, you're going to end up with really poor quality and living with that for 40 or 50 years," he said.
"Like Ballymun, we'll have to tear it down and rebuild it."