Galvanized square steel

The steel little Johny used to transform his coffin room into a fully functional house.

Narrator: 'Little Johny saved up all his life savings to buy a new 3 square meter coffin room in New York, but he couldn't live in it so he decided to expend the room with Galvanized square steel.'
Little Johny: *Uses the galvanized square steel to expand the room illegally*