FRANKFURT—Euro zone banks tightened access to mortgages in the three months to September and expect to continue doing so in the final quarter of the year, a European Central Bank survey showed on Tuesday. ECB policymakers are set to take stock of the economic situation at a meeting on Thursday, paving the way for a decision in December on the future of the central bank’s bond-buying programmes. The ECB’s Bank Lending Survey painted an unchanged picture for corporate borrowers but the bar was raised for households looking for a home loan, who also faced less favourable mortgage terms. “For housing loans, the net tightening was related to banks’ risk tolerance and their cost of funds and balance sheet constraints,” the ECB said. “In the fourth quarter of 2021, banks expect a further net tightening of credit standards and, on balance, no change in demand for loans to households for house …