Zend Layouts for Default and Admin

I have set up my app directory as follows :

application
---- modules
---- templates
---------default
---------admin
---- models
library


What I am trying to do is use default template for my public view and admin template for the admin module. I need to set my bootstrap up to switch the template for that single "admin" module. This was covered in Padraic Brady's tutorial but seems to have been taken down and I didn't have a copy of the source.

Could anyone advice me how to do this. The searches on forum for answers all seem to be different layouts per module.