Base builds the foundation of your treehouse before you ever put any walls up. The base is what supports everything else, so it’s important to do this step right. Base builds the foundation of your treehouse before you ever put any walls up. The base is what supports everything else, so it’s important to do this step right. Your base can come in many different shapes and sizes, depending on how you want your treehouse to look.
It can be rectangular or circular, made out of wood or concrete blocks. You can also construct a system of ropes and pulleys on the treehouse for climbing up and down. In this article, we explain the process to build a treehouse base in 8 simple steps.
Table of Contents
Choose an appropriate location for your treehouse base
Find a spot with room for both the floor and platform-level areas as well as space around the trunk where you can place the ladder rungs without damaging any branches or leaves. It’s important to choose a good location as well as make sure you have room for both the floor and platform-level areas.
The best kind of location for a treehouse is one that has plenty of room, like a large backyard or an open space in the woods. Not only does this provide enough space for the base, but it also provides room for any desired amenities which can include a porch or window boxes. A good location also has plenty of room to work with to plan accordingly before starting anything.
Build four posts underneath
The next step is to build four posts underneath your chosen tree. These need to be sturdy and should be buried deep enough in the ground so that they cannot move or wobble when you place weight on them. Build these posts first, before building your base. This will provide a stable foundation for everything else to rest upon later on. Use metal beams if possible as this makes it much easier to attach other things onto the beams without needing an excessive amount of wood screws.
Build two rails on each of the posts
After you’ve built your posts, it’s time to build two rails on each of the posts. Use treated lumber for these rails and make them as sturdy as possible. Build these rails on top of the posts- not around like a fence – and extend them away from the main trunk for about 4 feet (1.2 meters). This will be where your planks rest that form your floor, so this needs to be stable and safe enough to tread upon without risking any injury or accidents caused by falling through gaps in the flooring. If you’re using steel beams instead of wooden ones, then just weld them together.
Build the floor frame around them
With your posts set firmly into place, now you can start to build the floor frame around them! Build a rectangular frame with 2×4’s spaced 16 inches apart all around so there is no ladder access. Build this frame so there is no ladder access. The frame needs to be 4×6 because the tree trunk will take up 1 foot of space on each side, plus you will also need room for the floor to rest atop the frame (16″ apart). It should look like a rectangle around your posts, with an open space where your front door will be. Build it high enough off the ground that people won’t hit their heads if they walk into it wrong!
Build four support beams
With the floor frame now complete, you now need to build four support beams underneath it. Build these identical to the posts with 2×4’s. Build them about one foot shorter than your floor so they are resting on top of the 2×4 ledgers you’ve built for this purpose around your posts.
This will provide further stability for your flooring by preventing any gaps or shifting that may be caused by changes in humidity or just normal wear and tear over time. Build these beams at an angle sloping away from your trunk because if they’re not sloped then water could sit there after rainstorms and cause damage to the wood.
Build the floor
With the support beams in, you can now build your floor! Build this as neatly as possible with 2×4 treated lumber laid 16 inches apart. This is where it gets tricky because now you need to deal with building stairs and ladders as well as making sure the entire thing rests solidly on those four support beams without any gaps for people to fall through and get hurt. Build the base of each stairway securely before adding more platform levels up higher.
Build them using standard wood, not metal- just in case they’re needed later on by someone who isn’t you or a professional contractor. If you’re using treated lumber then it shouldn’t rot, but the extra safety of metal is always nice on stairs and ladders.
Build railings on all sides
Build railings around the entire frame for further safety. Build them so they meet building code requirements if you live in an urban area with strict safety guidelines. Build them sturdy with 2×4 pieces of lumber equally spaced apart. Make sure that anyone coming up or down the stairs of your treehouse has a handrail to hold onto at all times or else accidents could happen!
Build a roof
Finally, build a roof of sorts over top of your platform base by adding rafters onto what you’ve already built. Build these beams out from underneath the platform beams you already have in place. Build them at an angle away from the trunk, and then build a roof on top of that. Build this out of plywood or metal- it doesn’t matter which one you use as long as it keeps water off your flooring!
Building a treehouse base can be tricky, but it’s always worth the effort. The right kind of foundation will protect your house from rot and ensure that no one gets hurt in any accidents they might have while climbing or descending stairs.
A good treehouse base also determines the kind of designs and decorations that you would be able to fill your precious treehouse with. Build a treehouse base with love and care so you can focus on planning the rest of the structure, painting it a bright colour to match everyone’s favourite shirt, and making sure that none of your friends fall to their demise after trying to take a shortcut up or down.
That’s pretty much all you need to do to build a treehouse base- now make sure your kids are ready for bed before you start painting it with cool designs!