The consultancy, which hosted a seminar for house builders last week, voiced concern that emerging policy in the housing green paper means that many regional and local planning strategies are out of date.
GVA partner Gerry Hughes said: "Not only faced with a market downturn, the industry is being asked to provide three million new houses against a backdrop of outdated statutory plans and a confusing agenda."
The apparent lack of a clear planning regime means that house builders are likely to attack established policy on all fronts to capitalise on the situation, he added.
Meanwhile, GVA Grimley is to project-manage the expansion of the University of Cambridge on a 140ha green belt site to the north-west of the city.
It has been appointed to explore the commercial prospects for the scheme, which aims to create academic and commercial research space, student residences and 2,500 homes.
GVA Grimley partner Paul Watson explained that the university is aiming for a self-financing scheme so the market homes will subsidise both housing for key workers and infrastructure.
The firm will work closely with masterplanners EDAW and Peter Brett Associates, which is advising on highways and infrastructure.
Cambridge City Council and South Cambridgeshire District Council have gone out to consultation on a joint area action plan for the site.