I've finally gotten around to working on a treehouse in an area of our property that was overrun with blackberry brambles. Our neighbours generously helped pay for clearing the area, and with some recent nice weather I went into a treehouse-building frenzy.
First, of course, I needed to plan the thing out. For dimensions, I measured the tree trunk dimensions: one was 2' in diameter, the other 2.5'. They were around 10' from center to center. For a couple of feet of walking-around-space on either side of the trunks, I randomly picked a length of 16', width of 6'.
Note: 16'x6' is kind of huge for a treehouse. 16 feet is bigger than the deck of my house. Oh, well... I guess we'll just have to have parties up there or something.
Our neighbour suggested that she'd like to see a slide off of the treehouse, so after Googling for slides, it looked like many of the ones you can purchase for mounting on play structures expect to be mounted at 7'. So that's how high I planned to put the floor of the treehouse.
The freeware in question is a Google offering called sketchup. S'neat. Here's my first attempt at using the thing:
I spent hours tweaking the image, if not the design. The tweaking took hours, mostly b/c I kept accidentally telling sketchup to create odd shapes, like 2x6x8x16x6's. It's not easy to manipulate 5-dimensional lumber; it has a tendency to bend time and space, and isn't recommended for use in structures intended for children -- the little ones get sucked into alternate universes.
, and 
. The former gives a nice variety of ideas and advice about types of treehouses, and the latter is a nice complement to it. Looking on Amazon, there are a bunch of other highly-rated ones.
Considering the suggestions from the books, I updated the design to use 2x8's as the main supports, and have a floor frame of 2x6's resting atop them, also bolted to the trees. The books went into some detail about how to attach the beams to the trees, namely by using lag screws (lag screws! Snrk!).
After slooowly driving my lumber-loaded minivan home and carefully unloading the way-heavy planks off the roof, I started the meticulous process of mounting the 2x8's.
Ignoring the ominous "Danger! Danger! Don't do it!" music that was playing in the background, I nailed a single 3" nail approximately 7' off the ground through one of the 2x8's into the tree, then tip-toed to the other end and carefully lifted the other end up, using a level to figure out where it should to to be nice and flat. 2x8x16' planks are really heavy, and the trunks are nice soft squishy cedar, so of course the nail came out and I did an amusingly panicked little jig to get the heck out of the way.
Learning from my mistake, I repeated the process, this time... um... not doing anything different. The nail stayed in that time for some reason, and I marked the level point on the trunk above and below the plank. Then I nailed 2 nails into the trunk and tip-toed back to the other tree, using the level to ensure flatness. Then I yanked the board off of the tree, looking at the marks on the two trees and wondering where the ominous music went.
I cut a horizontal bite straight in to the trunk on the bottom mark around 2", then cut straightishly down above the top mark, eyeballing the resulting face to make sure it was pointing in the direction of the other trunk. Amazingly, it worked, and I had mostly retained my bodily parts. The ominous music got bored and wandered off.
I hoisted the plank back up, nailed it mostly in place (the other end was on the ground, so it couldn't quite sit on the lip yet), went to the other side, repeated the process, and pretty much went back and forth loosening and re-hammering until it was sitting levelly where I wanted it. I checked for right-and-left length as well, making sure there was approximately 2' of plank sticking out beyond both tree trunks. Then I brought out the 1/2" spade drill bit, made a couple of holes in the planks where the lags should go, and went through the odd process one of the treehouse books suggested, whacking the screws with a mallet, turning the screw a quarter-turn, and repeating 5 or 6 times. They were good and tight, crunching the washers into the boards slightly during the last turn.
The tricky part I was really worried about was the second 2x8. It had to be level not only between its two mount points, but also with the already-mounted 2x8. It wasn't as hard as I'd feared, though. First, I took a scrap 2x4 and rested one end perpendicular on the 2x8, pushing it against the trunk. Using a level, I made sure it was even, then nailed it to the trunk. I did the same with the other trunk. The theory was that the bottom of the scrap 2x4's would be the top of the second 2x8. Oddly enough, it worked! I held one end of the 2x8 up to the bottom of the 2x4, nailed it to the trunk, then repeated on the other end. I took another 2x4 and put it across the two 2x8's, checking with a level, and by gum the two 2x8's were even and level. Cool!
This side of the trunk was flat enough that I didn't need to chainsaw the thing. Four lag-screws later, the deed was done: two 2x8 beams were now securely mounted to the trees.
The last work of the day was to mount some 2x6's to the tree resting on the 2x8's. It was relatively easy: I rested the things on the 2x8's, made sure that they were centered between the two (by measuring the length from the ends of the 2x6's to where they met the 2x8's), and used 3/8" lag screws to set them tight to the tree.
One of the boards was really askew, so I unscrewed the thing and used a chisel instead of a chainsaw to flatten the area it rested against the trunk. It turns out that chainsaws are way, way faster. It took 40 minutes of dogged chipping away before enough wood was cleared.
Here's where things ended up after the first day:
(More details to come...)
Here's what it looked like after 2 days:
After 3-4 days:
First, of course, I needed to plan the thing out. For dimensions, I measured the tree trunk dimensions: one was 2' in diameter, the other 2.5'. They were around 10' from center to center. For a couple of feet of walking-around-space on either side of the trunks, I randomly picked a length of 16', width of 6'.
Note: 16'x6' is kind of huge for a treehouse. 16 feet is bigger than the deck of my house. Oh, well... I guess we'll just have to have parties up there or something.
Our neighbour suggested that she'd like to see a slide off of the treehouse, so after Googling for slides, it looked like many of the ones you can purchase for mounting on play structures expect to be mounted at 7'. So that's how high I planned to put the floor of the treehouse.
Sketchy behavior
Being of the geekish persuasion, I had to use a 3d modeling program rather than, say, paper and a pencil to visualize the plan. Why spend 10 minutes sketching when you can drain hours and hours into trying to master the basics of a cool bit o' freeware?The freeware in question is a Google offering called sketchup. S'neat. Here's my first attempt at using the thing:
I spent hours tweaking the image, if not the design. The tweaking took hours, mostly b/c I kept accidentally telling sketchup to create odd shapes, like 2x6x8x16x6's. It's not easy to manipulate 5-dimensional lumber; it has a tendency to bend time and space, and isn't recommended for use in structures intended for children -- the little ones get sucked into alternate universes.
Bookery
Anywho, after coming up with a suspect design for the platform, I started reading the books that Lissa checked out at our local library for safety and construction guidelines: the excellent, and . The former gives a nice variety of ideas and advice about types of treehouses, and the latter is a nice complement to it. Looking on Amazon, there are a bunch of other highly-rated ones.Considering the suggestions from the books, I updated the design to use 2x8's as the main supports, and have a floor frame of 2x6's resting atop them, also bolted to the trees. The books went into some detail about how to attach the beams to the trees, namely by using lag screws (lag screws! Snrk!).
There's no such thing as a dumb question. Except for the ones I come up with.
After learning how not to giggle so much when saying "lag screw," I went to the local Lumberman's and got down to the serious business of meandering around for 2 hours, asking dumb questions of the patient old guys behind the counter. I say "old guys," but they're probably just in their 50's, driven grey by newbies like myself asking dumb questions. My dumb questions included:- How many lag screws does it take to hold up a treehouse? (Extra points for keeping a straight face when saying "lag screws")
(Answer: put a couple of 5", 1/2" diameter lags in each contact point of the 2x8's, and one 5" 3/8" diameter lag in the 2x6's. That should do it. But you didn't hear it from me if it doesn't.) - How long does pressure-treated wood last?
(Answer: years. It depends on how the weather goes.) - How am I going to get 16 foot planks from here to my house in a 12-foot minivan?
(Answer: strap 'em on your flimsy factory roof rack. Sign here to release us of any liability for this, though...)
- two 2"x8"x16' base planks
- twelve 2"x6"x6' floor framing planks
- two 2"x6"x16' floor frame planks
- eight 1/2" diameter lag screws
- four 3/8" lag screws
- a slew of strong-tie hurricane ties:
H1's to strengthen the connection between the 2x6's resting on the 2x8's
LUS26's to attach the floor frame sides to the 2x6's.
Mountage
After slooowly driving my lumber-loaded minivan home and carefully unloading the way-heavy planks off the roof, I started the meticulous process of mounting the 2x8's.
Ignoring the ominous "Danger! Danger! Don't do it!" music that was playing in the background, I nailed a single 3" nail approximately 7' off the ground through one of the 2x8's into the tree, then tip-toed to the other end and carefully lifted the other end up, using a level to figure out where it should to to be nice and flat. 2x8x16' planks are really heavy, and the trunks are nice soft squishy cedar, so of course the nail came out and I did an amusingly panicked little jig to get the heck out of the way.
Learning from my mistake, I repeated the process, this time... um... not doing anything different. The nail stayed in that time for some reason, and I marked the level point on the trunk above and below the plank. Then I nailed 2 nails into the trunk and tip-toed back to the other tree, using the level to ensure flatness. Then I yanked the board off of the tree, looking at the marks on the two trees and wondering where the ominous music went.
Vrroooom!
The trees aren't completely vertical, so I thought it would be a good idea to take a bite out of the sides to have a little lip to rest the 2x8's on and have a flat area on which to mount the board to the trunk. Considering my pretty scanty set of tools, I chose the one that would make the loudest ominous music come back, so I got out the chainsaw.I cut a horizontal bite straight in to the trunk on the bottom mark around 2", then cut straightishly down above the top mark, eyeballing the resulting face to make sure it was pointing in the direction of the other trunk. Amazingly, it worked, and I had mostly retained my bodily parts. The ominous music got bored and wandered off.
I hoisted the plank back up, nailed it mostly in place (the other end was on the ground, so it couldn't quite sit on the lip yet), went to the other side, repeated the process, and pretty much went back and forth loosening and re-hammering until it was sitting levelly where I wanted it. I checked for right-and-left length as well, making sure there was approximately 2' of plank sticking out beyond both tree trunks. Then I brought out the 1/2" spade drill bit, made a couple of holes in the planks where the lags should go, and went through the odd process one of the treehouse books suggested, whacking the screws with a mallet, turning the screw a quarter-turn, and repeating 5 or 6 times. They were good and tight, crunching the washers into the boards slightly during the last turn.
The turn of the other, other screw
The tricky part I was really worried about was the second 2x8. It had to be level not only between its two mount points, but also with the already-mounted 2x8. It wasn't as hard as I'd feared, though. First, I took a scrap 2x4 and rested one end perpendicular on the 2x8, pushing it against the trunk. Using a level, I made sure it was even, then nailed it to the trunk. I did the same with the other trunk. The theory was that the bottom of the scrap 2x4's would be the top of the second 2x8. Oddly enough, it worked! I held one end of the 2x8 up to the bottom of the 2x4, nailed it to the trunk, then repeated on the other end. I took another 2x4 and put it across the two 2x8's, checking with a level, and by gum the two 2x8's were even and level. Cool!
This side of the trunk was flat enough that I didn't need to chainsaw the thing. Four lag-screws later, the deed was done: two 2x8 beams were now securely mounted to the trees.
The turn of the other, other, other screws
The last work of the day was to mount some 2x6's to the tree resting on the 2x8's. It was relatively easy: I rested the things on the 2x8's, made sure that they were centered between the two (by measuring the length from the ends of the 2x6's to where they met the 2x8's), and used 3/8" lag screws to set them tight to the tree.
One of the boards was really askew, so I unscrewed the thing and used a chisel instead of a chainsaw to flatten the area it rested against the trunk. It turns out that chainsaws are way, way faster. It took 40 minutes of dogged chipping away before enough wood was cleared.
Here's where things ended up after the first day:
(More details to come...)
Here's what it looked like after 2 days:
After 3-4 days:
