BUILD YOUR OWN TREE HOUSE

First, find your tree. Then, make your plan. Then, be ready to adapt that plan.

THE FIRST rule of tree-house building is that it all kind of depends on the tree. You can model yours on this one, or on your neighbour’s, or on one you saw on Treehouse Masters, but the tree (or trees) in your garden will be different – thicker, farther apart, closer together, stronger, weaker – and your design will change accordingly.

The second rule is the kids should be involved. The building of a tree house was a major selling point when we told our boys we were moving out of the big, exciting city to a sleepy rural town. I still have our older son’s hand- drawn plans for what he wanted it to look like. ( It’s close.) And they both drove some nails and screws, and found some cool branches that we incorporated into the design. They participated.

The last rule is it’s not going to end up the way you think it’s going to end up. Meaning: The plan will change as you goon . New ideas will form once you’re up in that tree. And other ideas will prove undoable. Branches will get in the way, and things will generally look different from the air. Even a few metres up. So improvise. Adapt. Make it yours. Or, to be more precise: Make it your kids’.

1/ SUSPEND THE FLOOR JOISTS

I chose a tree with two trunks and measured 3 metres up each. For the floor joists, I used three 45 × 297 mm boards and fanned them out from the 3-metre mark on each trunk: one on the outside edges of the trees, and one threaded through the V in the middle. I propped the ends in place using 100 × 100 mm posts as jacks and clamps to hold them steady, then I ran 1-metre 6 mm galvanised-steel tie rods (A) through all three joists (but not through the tree trunks). I clamped the boards snugly to the trunks by adding nuts and washers to the ends of the tie rods. So, at this point, the three big floor joists were splayed out into the air, one end propped up by a 100 × 100 mm post, the other clamped to the trees.

2/ FASTEN THE BASE AND BUILD THE FLOOR

Those 100 × 100 mm posts on the out-in-the-air ends of the joists became permanent supports, strengthened by diagonal 38 × 114 mm struts. Screw the joists to the 100 × 100 mm posts using exterior-grade fasteners such as 80 mm structural screws. Then, add the struts, as pictured ( C, E), to prevent the supports from wobbling. Next, screw down a floor. Spanning across the joists, I used alternating 38 × 114 mm and 38 × 152 mm, for a more rustic, interesting look ( B).

3/ ADD RAILINGS

I left the ends of the floorboards staggered (as opposed to flush with one another), so the upward struts of my railings are staggered, too ( B). I simply measured 38 × 114 mm boards to the same length and fastened them to the ends of each floorboard, using more structural screws, then added a flat railing along the top all the way around. For variety, the kids found some interesting branches around the yard, and we substituted those for some of the struts ( D). I improvised as I went: If a corner didn’t seem strong enough, I added enough support to make it strong. Where the railings meet the trees, I attached a wood block, using as few fasteners as possible, to act as a base for the railing to affix to – a start, or end point, for the railing.

B