Ann: Intention to demerge Coles - Briefing Presentation, page-66

Bunnings has not even addressed 20% of the home improvement market, so there is still plenty of blue sky for them. The home improvement market has been characterised by the 'Blue Ocean Strategy' whereby they do not just address the existing market, but go after markets such as the outdoor living market (i.e. the outside living concept [outdoor pizza ovens] etc).
They are miles away from having to worry about that in the same way that Woolies and Coles have had to.