Nick Adams’ $100,000 Treehouse

In the Adams' Gladwyne backyard, a soaring structure sets the scene for fantastical battles, late-night card games and epic water balloon fights.

Inspiration: When I was a kid, I climbed a hemlock and built myself a treehouse out of a bunch of wood planks. It was home, but it was also a hazard.

Design: My wife, Dee, and I have three boys and one girl—13, 12, 11 and eight. Each drew their version of a great treehouse, and architects Matt Seip from Chase Building Group and Scott Larkin from Brawer & Hauptman incorporated all their ideas into this design.

Outside in: The structure embraces a huge tulip tree, giving the feeling that it grew out of it. The canopy of leaves serves as the roof.

Amenities: A drawbridge, a trapdoor, a catapult on the top floor for water balloons, and a pulley system that goes all the way to the bottom so you can pull your supplies and ammo up.

Quiet time: At night, we bring out lanterns and play board games here. It’s where the boys learned to play a mean game of Texas Hold ’Em.

Wood: The basic structure is Spanish cedar; the floors and planking are ipe from South America.

What’s inside: A few built-in benches, but it’s pretty much open. You climb la­dders to go from floor to floor, like on a battleship.

Battle zone: There are slits in the walls, like in castles, so you can fire your Nerf guns through them. It’s a perfect place for pitched battles. My daughter loves to picnic here, too—­during periods of peace, of course.

Cost: Just over $100,000. So yes, it was not inexpensive.