"As a prudent lender, ahead of someone securing a mortgage, affordability checks on the mortgage applicant, a valuation and inspection of the property by the warranty provider needs to be carried out.
"All of these will determine whether a mortgage offer will be issued.
"We would also urge customers to seek independent advice before entering into such a significant, long term financial commitment."
Meanwhile a spokesman for Lloyds said: "As part of our ongoing commitment to the market, we continue to work closely with the house building industry directly and through UKF, supporting housebuilders to improve outcomes for our customers who choose to purchase a new build property."
A spokesman for Bovis said: "Over the last year we have made huge changes to our build quality and customer service and have transformed Bovis Homes.
"Currently the percentage of our customers across the country who would recommend us to friends and family shows a 30 percentage point improvement on where we were at the same time last year – with a running score trending solidly in the high 80s.
"This is based on returned surveys in the current HBF year, which started on 1st October 2017."
RICS and the NHBC did not respond to a request for comment.