Does the foam pile up or spread quite thinly if its not contained?
The foam does pile up to a certain level before it starts to spread if not contained. A rough estimate would be that it piles up a metre and extra foam falling on top will spread out to the sides. We did not contain the foam at the Curtin Tavern foam party and the foam still piled up pretty good. You can get a good idea by viewing the Curtin Tavern foam party photos by clicking on the link on the Gallery page: “Curtin Tavern Party Pics”. Nevertheless, it would still be a good idea to contain the foam around the sides.
