Mortgage brokers still originate around a quarter of all residential lending for Heritage Building Society, and the leading institution in its sector says it has no plans to sever these ties as so many of its peers are doing.Even so, broker commissions are under review, according to chief executive officer John Minz."We will continue to offer loans through brokers, based on our understanding of the current environment," said Minz."I think the whole market place has changed; I think there will be a fair amount of amalgamation and rationalisation in the broker environment. The rules will change. "We have already seen a number of banks that have looked at commission rates paid both upfront and trail."We are reviewing our arrangement at the moment; we won't be a leader, we will see what happens within the industry and then we will determine, based on what happens, what an appropriate arrangement would be for our broker partners."The business that comes through brokers has allowed us to become the biggest building society by allowing us to tap into borrowers and business outside Queensland."It also allows us to obtain geographic diversification, which is all about risk management."Standard & Poor's cut Heritage's rating to BBB from BBB+ in March, with Minz saying there have been no major consequences."No, there are no consequences other than the fact it makes us very determined to get the plus back, and we are doing a whole range of things in our funding area that are yet to be announced, including sourcing an exchange settlement account."In terms of affecting the business, no, since they have taken it (plus) away our wholesale deposits have actually stabilised and have begun to come back up again."It's the existence of an investment grade rating that is important."Heritage in the past has been a heavy user of securitisation, with Minz adding the residential portfolio is currently around 47 per cent securitised."At the moment we are not tapping into securitisation."It suits us to be able to tap into alternate funding arrangements."Minz adds the year to date retail deposit portfolio is up 14 per cent. "It (securitisation) is something that will continue to decrease as a percentage of funding sources for Heritage. The percentage of funds that we are able to have on balance sheet through retail and wholesale will increase. Our strategy has been in recent times to look at other funding options - this week releasing a farm management deposit account."We are looking at a number of other retail-based funding products."Mortgage arrears 30 days plus are 0.4 per cent.The Toowoomba, Queensland based Heritage has 59 branches.