The Government broke Treasury rules in order to launch its flagship Help To Buy policy by failing to carry out any of the assessments of alternative schemes, PAC have said.
Committee chair Margaret Hodge criticised the Government for failing to be cautious before handing out £10bn in loans.
This means it has committed to spending up to £10 billion on supporting Help to Buy without establishing whether it represents the most effective way of using taxpayers' money to achieve its objectives.
The department will not carry out a comprehensive evaluation of the scheme until 2015, by which time billions of pounds will already have been spent.
More top news
A council will hand out £100 fines to dog walkers who leave home without poop bags regardless of whether their pet fouls or not.
Wales has become the first UK country to make every adult a potential organ donor.
Interference from Christmas fairy lights can slow down broadband connections in the home, energy regulator Ofcom has warned.