Dave's classic domino rally

Here's a description of the contestant's attempt. Someone's probably working on collecting some images to illustrate it.

Dave creates a classic domino rally in the living room by using just the dominos provided. His rally starts on a high shelf and then drops down to the floor, before continuing out through the external door and down the steps into the garden. He uses 434 dominos in total, and earns second place.

(Written by JoGo and proofread by Karl Craven)