Police said the bill was expected to run into hundreds of thousands of pounds after the blaze in Wallacewell Quadrant in the Balornock area.
Firefighters and police were called to the scene about 7:30pm yesterday. No-one was injured, but the fire is being treated as wilful.
Detective Constable Gillian Paddon said: “Extensive damage has been caused to the site where new homes were being built for the area and it is absolutely imperative that we trace whoever is responsible for this reckless and dangerous crime.
“I would appeal to anyone who noticed any person or people acting suspiciously in the area of Wallacewell Quadrant yesterday evening to please come forward.”