The 7 Rules for Building a Treehouse


Photo credit: Animal Planet

Pete Nelson doesn’t build your everyday backyard treehouses. He is the author of several books on the subject, the owner of Nelson Treehouse and Supply in Seattle, Washington, and star of the hit television series “Treehouse Masters” on Animal Planet. So, how fancy do his outdoor structures get? Envision a jaunty pirate ship, meditative retreat, and a brewery tasting house with Gothic stained glass windows and cathedral ceilings. If you can dream it, odds are he can build it. But how do you build a treehouse of your own?


1. Think “Tree” First, “House” Second

“Trees drive the whole design,” Nelson says. “You can have a vision of what you’d like and the tree can actually get in the way of it.” For this reason, it’s best to consider the tree and surrounding landscape before you even begin to map out your design. Consider the maturity, health, and structure of your tree.

2. Know the Right Tools of the Trade

Nelson never embarks on a project without the following tools at his disposal: a compact screwdriver set, a circular saw, wire mesh, and galvanized bolts and treehouse attachment bolts (TABs), which strengthen the beams connected to the tree and bears the weight of the treehouse.

3. Use a Solid Support System

The platform is the foundation of your treehouse — this is constructed with beams situated parallel to the ground and supported by treehouse attachment bolts (TABs). Nelson suggests that the platform have a span of 12 to 15 feet, “After that, the beams get bigger and bigger.”

4. Never Touch the Tree

In other words, the treehouse itself should never come in contact with the tree. Instead, the house should rest on the supporting platform. It should stand 6 to 8 inches off the bark. This accommodates for the tree’s growth in girth and natural movement. Otherwise, the structure will rub against the tree as it sways in the wind.

5. Allow for room in your schedule (and budget)

“It will take you ten times longer than you plan,” Nelson says with a laugh. A basic treehouse will take about 300 hours of labor, aside from artistic liberties that change your design. In terms of finances, Nelson estimates that a basic backyard treehouse will cost $10,000 or less. That includes materials and hardware, but not necessarily extra expenses like flags, tire swings, and interior decor.

6. Talk to your neighbor

It’s a common courtesy that can save you conflict in the long run, especially if you plan to build the treehouse on shared land. You don’t want the treehouse obstructing their view or invading their privacy. It’s also a good idea to research your local regulations or ordinances.

7. Construct on the ground

Do as much of the work on the ground as you can, Nelson says. “It’s safer, it’s faster, and it’s more efficient.”