Normal kids had tree houses made of rotten planks, rickety furniture and a mismatch of nails. My father is an aerospace engineer and would never stand for shoddy workmanship. When I was 7-years-old he built us a playhouse complete with double pane windows, fiberglass insulation, electricity, and a full-sized door. It was a 5X5 home complete with old furniture and lacking in cobwebs. If we’d grown up in NYC and he’d installed plumbing, we could’ve rented it out to students for about $1000 per month.

Still, whenever it came time to play, we always decided against the tree house and took to the crawlspace under the stairs, single bare lightbulb swinging above us, straining to see our boardgames and comic books. My brother and I had a fascination with hidden stairways, Scooby Doo and the Hardy Boys. It was a natural spot for us.

I can’t help but think if my father had known about Creative Home Engineering he might have gone for something more covert. I spent a few hours last night looking at videos of secret doors and crawl spaces and stumbled upon one of the best secret passageways I’ve ever seen. Check out this fake swimming pool in Japan: