Installing Walls

On an ordinary construction job, a wall raising is the day when a few extra helpers show up to tip up the walls and assemble the house frame. With a treehouse, wall raising gets a whole new meaning. It’s time to call out your burliest neighbors, or get a little mechanical help from a block and tackle.

To get ready for the wall raising, snap chalk lines on the platform floor to represent the inside edges of the walls’ bottom plates. With an accurate chalk line layout, you won’t have to worry about squaring the walls as you assemble them.

For a small treehouse with light walls, lift two adjacent walls up onto the platform, set them on their chalk lines, and fasten them together through the end studs with 3" deck screws. Install the remaining walls one at a time, then anchor all of the walls to the platform floor framing with 3-1/2" screws. Drive a few longer screws at floor joist locations.

For larger houses with heavy walls, lay one wall flat on the platform, then tip it up and set it on the chalk line. Anchor the wall’s bottom plate to the platform with 3-1/2" screws or 16d galvanized common nails, then add temporary 2 × 4 bracing to keep the wall upright. Hoist up the adjacent wall and fasten the bottom plate, then fasten the two walls together through the end studs. Repeat for the remaining two walls.

When all of the walls are up, cut out the bottom plate at the bottom of the door opening, using a handsaw.