Westpac looks for expansion on home loans WESTPAC is planning to aggressively expand its mortgage book to address falling market share, suggesting competition in the $1.3 trillion home-loan market is unlikely to decrease. At the bank's first-half result on Friday, Westpac chief executive Gail Kelly said she wanted to see its mortgage growth pick up in the second half after growing at about 0.8 times system growth across its portfolio of brands, including Westpac, Rams, Bank of Melbourne and St George.