The warehouse was a building owned by Gordon Way. It was the building in which he built a time machine to travel back in time. It was down the end of the street from Ruth and Susan's houses.
Dirk and Richard entered the warehouse after Richard suggested it as a possible location for the missing Henry the cat. Dirk picked the lock and they entered to find a mysterious machine inside. Dirk noticed paw prints on the ground leading up to the machine and a rose petal on a metal sheet.
Dirk tapped a button and the system self-destructed, blowing up the warehouse.