How to Build a Foundation for a Tree House

Make a simple tree house or a more complicated one.

Before starting a tree house project, check with local zoning officials to make sure tree houses are permitted in your neighborhood. Like swimming pool diving boards, tree houses have been zoned out of many neighborhoods. Also consult with neighbors before you start, especially if the proposed location could compromise the neighbors' privacy.

Things You'll Need

• Nail gun or screw gun
• Lag bolts and washers
• Pressure-treated 2-by-6s
• 7/8-inch treated 4-by-8 plywood
• Hoist

Instructions

1. 

   Look for a deciduous tree with a thick, strong trunk for the tree house location.

   Choose a tree big enough to support the planned structure. For example, a single trunk should be at least 12 inches to support an 8 ft. x 8 ft. treehouse. Smaller minimum diameters work if the tree house will be supported by more than one tree. Deciduous trees tend to be the best tree house supports.

2. Minimize tree health impact. Avoid notching into limbs, if possible. Use lag bolts and washers instead of nails or screws to secure the foundation. Limit cuts that may interfere with the growth cycle of the tree.

3. 

   Use pressure-treated lumber to increase tree house life.

   Assemble the foundation on the ground with 2-by-6 pressure-treated boards, then hoist it into the tree. This will be quite heavy. Adjust the foundation until it is as level as possible before bolting it to the tree.

4. Drive screws to attach ½- or 7/8-inch thick pressure-treated plywood onto the foundation.

Tips & Warnings

• Try to avoid building around limbs so that they grow up through the house.

• Leave the tree some grow room between itself and the tree house.

• This is an advanced building project, if it is done correctly. Do not attempt it alone or if you have no experience.

References

• How to Build a Tree House | Everyday Guide
• How To Build A Tree House?

Resources

• Tree House Plans - How to Build a Backyard Tree House ...