Suncorp Bank's non-core loan portfolio reduced by A$500 million in the September quarter and now makes up only eight per cent of its consolidated bank loan portfolio.During the financial crisis Suncorp carved out a portfolio of corporate loans, development finance and property investment loans, which it put in run-off. In 2009, that portfolio made up 32 per cent of its total lending assets.The bank has a very conservative profile these days, with mortgages making up 72 per cent of total lending assets.Despite operating in the heart of one of the most difficult finance markets in Australia - south-east Queensland - Suncorp reduced its impairment losses and its impaired loan balance during the September quarter.In a quarterly update issued yesterday, the bank said impairment losses fell from $19 million in the June quarter (representing 0.34 per cent of credit risk weighted assets) to $16 million in the September quarter (0.28 per cent of credit risk weighted assets).The impaired and past-due asset balance fell from $241 million to $235 million over the same period.The bank said the $16 million impairment loss was due to a small number of business loans.Past-due loans have fallen as the problems associated with the Brisbane floods in 2011 have been overcome.An indication of the bank's conservative stance is that the size of its average mortgage is below the national average of $300,000.