Our Great Treehouse (Railings + A Modern Roofline)

I think there’s a lot to be said about making long term investments like this at your home. The whole process of building the treehouse for our kids challenged us to create something that we’ll have for a long time, and we’ll be happy with for as long. Something suitable for everyday play, fun for a wide range of ages, and also, good lookin’, since we’ll be staring at it through our kitchen window for the next however many forever. I consider myself healthily frugal, but went into this project with a budget realistic of what it would cost to buy a play set (and the better versions of those things aren’t cheap). We saved here and there by reusing hardware that we had on hand, wood scraps from previous projects, and by being efficient and using almost all of the new wood we bought, but longevity was a main consideration in every stage of construction, and where we needed to invest to guarantee that this treehouse would stand up to wind, rain, rot, and anything else fathomable, we did. It repels elements.

I’ll go through all of the receipts to see what this structure has actually cost us (goal: <$1,000?).

Safety features, obviously, weren’t something that we’d cheap out on, and this treehouse probably has the best railing that we’ve ever built. More than anything else, I think this proves that practice in DIY makes perfect because sturdy railings are more complex than you would think, and it was the step of the project that I was most weary about. I’ve built some railing systems in the past that required a lot of tweaking (not twerking, there was almost an embarrassing typo right there) to prevent them from feeling loose, and I wanted/needed these to be right on the first try. From experience, it’s really best to anchor the railing posts to real structure (don’t even bother screwing around with those metal cups, metal cups are phonies). To do this here, I cut away part of the T1-11 paneling that I had already installed and stained so that I could bolt the vertical railing posts down and through the installed floorboards, directly to the structural end joist.

The order of operations of construction may have been a little bit whacked in this case since I ended up removing something I had already deemed “complete,” but it got done well, and I can rest easier now that it’s installed. The placement of the ladder was something we hadn’t firmly landed upon prior to this step, and the 11th hour decision to install it coming up the backside meant that we would be able to have one long stretch of railings, which would look good, and promise a more sturdy railing structure.

For the balusters, I loosely followed a railing design that I liked in one of my inspiration photos, but retrofitted the materials list to fit a modest budget because cute railings made of premium wood can be damn expensive. Instead of buying ridiculously priced lumber that might look like crap after one season out in the snow and rain, I bought a bunch of 6-foot 1×6 fence boards, and ripped them to size. They’re pressure-treated, and fence boards are notorious for lasting a long ass time.

A single 6-foot 1×6 fence board, even after chopping off that classically fancy fence post end, was enough to yield 4 individual homemade balusters at the length we needed for our 30″ high railings. We used the chop saw and table saw here, which made the process quicker and more accurate than using a circular saw.

My ol’ friend the Kreg Jig doesn’t get much use these days, but came in handy while constructing the horizontal structure of the railing so there are no awkwardly exposed screws or bolts. We attached the 3″ wide balusters with 1-1/2″ deck screws by starting in the center, and working outwards, using a spare baluster as a spacer. Without much planning, this worked out pretty well. We later went on to add a 2×6 board across the top to create a flat rail, which you’ll notice in some of the photos later in this post.

The ladders for the treehouse were another big decision; we actually had two to make, the second of which you can sort of see if you look really hard through the chop saw in this picture.

The first resembles your everyday ladder, but with foot treads like steps. Had we given a little more thought to the placement of each step, we definitely would have spaced them out a little bit more (we went with a standard 8″ rise, but didn’t account for there being virtually no tread “run” so if you’re not careful, anyone with adult-sized feet can get pretty tripped up (or down, I may have already fallen down). This one may get rebuilt eventually for convenience, but not immediately because so far the kids are nimble enough to not get tangled in their own sneakers (not to mention, tiny feet). It does look damn good though, and I’ll always appreciate the way Pete took the time to dado and chisel this to visual perfection.

That second ladder provides access into the treehouse through a small “trap door” opening in the floorboards (there’s still no “door” and may never be – pinched fingie alert!). This ladder style is a little more straight forward, and easier to climb too. Since you’re accessing straight up into the treehouse, I added dowels into the wall here to grasp onto as you’re entering the enclosure.

The cement pavers that we used beneath both ladders were something we inherited awhile back when we lived at the old house but never used (but since we bothered to haul them from house to house, and then left them leaning against a tree for 14 months, they weren’t easily forgotten about and happily found a permanent home).

The ceiling structure was a detail I anticipated as much as I did the round window (read about how we cut that round window here); to keep in the modern look and feel, we constructed the roof to be slanted (I think it falls 16″ over 12-feet), which is also enough to allow rainwater to easily flow off. Best case scenario, the roof would have completely covered the front porch area too, but our measurements (or lack thereof) made the overall treehouse a little longer than we envisioned originally, and so we settled with an even ~12″ overhang on the front and back, which I think worked out beautifully.

Each of the three boards up there was hand-notched out by Pete to allow it to sit in place, and was also toenailed securely with the framing nail gun (we used that tool a lot during this project; highly, highly recommended). We considered adding hurricane ties for added reinforcement, but without them it felt really sturdy, especially once we began layering on the ceiling structure that ran perpendicular. They’re always something that we could add on later, since it’s an open structure.

Somewhere in between finishing the railings and ladders, and installing the roof, we sprayed the raw woods with more of the opaque Oxford Brown stain; in our second round of staining, I noted intentionally that we were diluting the opaque water-based stain by 50%, which did a lot to stretch our second gallon of stain and finish the job without completely eliminating the opacity of the stain. (Read more about the staining strategy here.)

The roof was one of the only materials we knew we wanted to use when we started this project; we figured it would be easy to find something corrugated, like your average shed or your grandma’s carport. I like fabric roofs on play spaces well enough, but they’re a little more temporary than I cared to install here (my mom was always sewing new ones for my childhood treehouse using sailcloth, crafty lady). A roof finished with shingles was a viable option too, if it wouldn’t have made the treehouse seem too… professionally finished, and nicer than our barn. Our color preferences limited us in the corrugated department, and the fact that we needed pieces that were 12″ in length narrowed us down to a Polycarbonate roofing product at our local Lowe’s (those tall sheets on the right):

Naturally, can’t really see the actual product that we bought in that above photo; it’d be the dark/black panel peeking out to the left of Pete. It’s most closely described like sunglasses, transparent but tinted, so when used as a roofing material, you can see straight up through to the sky, but be shaded from the direct sunshine.

We had to get a couple of boxes of special screws to attach this – if you were to drill right through the plastic you’d be dealing with water leaking issues, so the recommended fasteners have a rubber gasket-like seal on them to help divert rainwater. At roughly $33/each, we needed 5 sheets of the polycarbonate and 2 boxes of screws to account for the necessary overlaps in panels, so it might not have been the least expensive route, but it has definitely been keeping our treehouse dry and letting in enough natural light to enjoy the space into the evening.

If you want to talk about saving a few dollars, the ceiling braces that run directly below the plastic roofing were ripped from leftover deck boards, a quick way we managed to save ~$15. I also didn’t stain the top of them, because why?

We’re considering it “done” for awhile; we’re still going to install swings at some point in the coming weeks, but the novelty is in the treehouse itself right now, so we’re not rushing ourselves on it. Also, there are some finishing touches that I’ll add to the interior as I get around to it (paint treatments, pulley system, pegboards), and when I find the right set of outdoor children’s furniture, I’ll scoop it right up so Julia and her friends have a comfortable place to play with their toys and make me precious art. The kid art is incredible lately.

Before I head out, I’ll leave you with some photos that I took this morning:

While spraying stain, Pete accidentally coated two of the cement blocks. May eventually go back and stain the others. May decide that I don’t care.

Inside, super spacious. Hole in the floor is the secondary entrance… still in need of a guard rail of some sort. The view from the half wall is wonderful, looking through vines and down into our ravine.

In any case, it’s still completely unreal that in April, this area was still entirely overgrown…

… and now it looks like this. (How’s that for a holy crap moment?)