Are you sure you have run out of space in the house?
What about removing the plinths under the kitchen base units and storing tins on the floor under the kitchen cupboards, what about lighter on top of the kitchen cupboards?
What about removing the bath panel and storing stuff under/around the bath?
You'd be surpised how much stuff can be hidden away in places like these....get creative you don't want stuff to spoil outside if you can help it!!