What should I include in an awesome treehouse?

April 23, 2009 8:26 AM

So I want to build a treehouse for my kids...this is a very rough sketch of what I'm thinking about. What would make this treehouse super cool?

I have two little girls (nearly 5 and nearly 3) and a new baby due this fall and I want to build a cool treehouse for them. The idea is basically an elevated deck with a rustic fort in the back corner. I want to put in a couple of swings underneath it and a fourteen foot slide with a ladder next to it.

Help me brainstorm what should be in the coolest treehouse ever.

posted by ColdChef to home & garden (67 comments total)

Secret hiding place! My friend's tree fort had a secret spot under the floor boards that she stored playing cards and candy in.
posted by muddgirl at 8:35 AM on April 23

A periscope. Simple enough to build with some PVC pipe etc.
posted by le morte de bea arthur at 8:39 AM on April 23

And a flagpole with a selection of flags (maybe get your kids to design them)
posted by le morte de bea arthur at 8:40 AM on April 23

I am now grown and I never had a tree fort because my parents hated me or something. All I got was a sandbox.

In spite of that - or perhaps because of that - I have often thought about what would have made me super happy if I had had a tree house as a kid. I don't think all of these ideas are good, or even possible, but I'll just toss them out there.

Slides and ladders and swings are always awesome, so good on you there.

I was also always very keen on the idea of a trap door in the floor of some variety.

I also always liked the metal pole as a mechanism to descend from a fort. What kid doesn't want to slide down a pole like a fireman?

Also, a faux-periscope of some variety is great. Gives kids the sense that they can hide out and kind of "spy" on what's going on.

Things with ropes are fantastic. Zip lines can be huge and dangerous, but they can also be short runs and mostly safe and still exciting.
posted by kbanas at 8:41 AM on April 23

The coolest treehouses are always the ones kids build themselves.

Yes I realize your kids are too young for this now but when I was about thirteen a friend and I built a treehouse, and a completely kickass one. It was an ambitious project, supported between three trees (later extended to a fourth), with proper decking, and a hut in the middle, doors on each end, corrugated fiberglass roof, heavy carpet flaps over the windows (we were into paintball then, you see). A few other friends helped sporadically but, for the most part, we did it all on our own, with no help from adults.
posted by 6550 at 8:44 AM on April 23

Electrical outlet - for sleepovers, and for the radio to listen to baseball
slingshot mounted on a railing so it can pivot
hammock underneath (you built it, you might as well hang yourself a hammock from it)
posted by stupidsexyFlanders at 8:45 AM on April 23

Don't know if you caught this thread, which has some fort stuff in it... Maybe some ideas here, too.
posted by hermitosis at 8:45 AM on April 23

Well, as it is, it's not really a 'treehouse,' since the tree doesn't support any part of the structure. Maybe nail some boards to the tree, making a ladder up to the roof of the fort area. (Of course also put railings around the roof.) That would integrate the tree more, plus it would be super cool- the more levels the better!

The largely open area underneath should be half enclosed by some kind of wooden lattice. It would be especially neat if you planted beans or some other vine around it, making a kind of secret arbor. I spent a lot of time just hanging out under a big bush as a kid because it felt like a secret forest clearing in there.

I'd want to have furniture, just a couple of chairs and a table, in the fort.

Some kind of pulley system with a bucket would rule.
posted by showbiz_liz at 8:45 AM on April 23 [3 favorites]

If you're already getting PVC pipe for a periscope or somesuch, get a ~8 foot length of 4" diameter pipe and two elbows and set it up so your girls can talk though it. I remember this was set up at Compo Beach in Connecticut when I was a kid and thought it was the coolest thing ever.
posted by Inspector.Gadget at 8:45 AM on April 23

Cool in a different way:

The neighbors raised some ruckus about my childhood fort. It was too close to the fence, you see. There were regulations about that. My solution: turned it into a trailer. Slapped some wheels on it, slapped a pair of tail-lights (unconnected to anything) on the back. It was legal enough to get a little license for it. Thus, the fort became, in a legal fiction, a trailer, and the neighbors just had to deal with it.

The wheelwells, on the inside, did make for a good way to stash things. Put a lock on the door. Teenagers will attempt to get drunk anywhere, I found.
posted by adipocere at 8:45 AM on April 23

Also be sure to string outdoor lights all over it to extend the playtime past dark
posted by stupidsexyFlanders at 8:46 AM on April 23 [4 favorites]

Come cool lanterns or tube lighting around the tree, or the house for hanging out after dark. Solar powered maybe, so you don't have to run electricity?

Mesh on big windows to keep out bugs?

An umbrella for the table and chairs, so they can sit outside, but have more consistent sun protection than the tree.

A diving board on the deck for the pool you're going to put in.
posted by Brandon Blatcher at 8:47 AM on April 23

Rope ladder. Climbing wall. A pole you can slide down. Monkey bars.

Oh man, I love our play structure so much it hurts. I swing almost every day.
posted by padraigin at 8:48 AM on April 23

* Trap door with emergency pole to slide down.
* The ability to pull up the stairs like a draw bridge
* Some sort of basket / pulley system to bring up goods
* Outdoor wireless speakers to play music
* Tennis ball launcher potatoe gun to keep the dragons at bay
* Twisty enclosed slide instead of a regular one
posted by bleucube at 8:51 AM on April 23 [1 favorite]

2nding electricity. I had that in my tree house and I practically lived out there in the summer when I was a teenager, as I could have an alarm to wake me up for work. Plus, it was fun to dig the trench for the power from the barn.

The trap door was also great, as were bunks that folded out, so I could have some one to sleep over and I got to sleep up high (I really like sleeping up high).
posted by chiefthe at 8:55 AM on April 23

Under the club house you might want to put up some cross pieces they can dangle from and use as monkey bars.

Since it isn't in a tree per se they may like it if you grow a vine all over it so it looks more secret. The only downside may be more bugs or bees if there are flowers.

Do they have any favourite books or fairytales you can incorporate? (like rapunzel - requiring a turret, a window an a knotted rope to climb down)

Include storage of some sort that is bug/weatherproof (like a big rubbermaid tub) for their dressup clothes.

A clothesline message system between the clubhouse and kitchen for important snack top-ups.

Shutters and windowboxes (flowers have to be shorter than shutters obviously).

Curtains underneath so it can b a stage. Maybe box in one narrow end underneath with just an oversize opening that can function as a puppet theatre or storefront or drive-through etc.

Including a way to make music is pretty cool, such as wind-chimes or bamboo pipes you set up so they have to be hit with a mallet. Kinda like a home-made xylophone. Anything that makes music is cool.

A raingage, theremometre, wind sock, barometre glass. Anything for a weathher station. Speaking of weather, rain sounds awesome under a metal roof, would it make it hot though?

Use passive solar techniques to keep it climate controlled (wide overhangs on windows), good flow-though of air.

Is this where we are having the NO meetup?
posted by saucysault at 8:58 AM on April 23 [2 favorites]

Nursing baby + typing = typos. sorry
posted by saucysault at 9:01 AM on April 23

All treehouses require a pulley on which rests a loop of rope to which two buckets are tied, each at one end of the rope loop.

And a trap door.
posted by odinsdream at 9:08 AM on April 23

When I was a kid, I longed for a manual elevator for our treehouse. It would take some doing to ensure safety. You'll need guide rods and a simple block & tackle system with a hand crank. When the elevator is down, a center guide pole can double as a fireman's pole!

Alternatively, try the rope counterweight system that they use in Robin Hood, Prince of Thieves.
posted by RobotNinja at 9:11 AM on April 23

I mostly just want to say that I fully support this treehouse project, as I had a similarly-designed treehouse built for me by my pop-pop when I was a kid (I have a blog entry about it here with some pictures).

The one thing I always wanted for it was kid-sized, but adult-like furniture, like the mini sofas and recliners that I always saw in mail order catalogs. Also, a pirate's treasure chest, with a key so your kids can stash things in it, would be cool.

Once it's built, no snooping, though. And don't later tell your kids how you sneaked cigarettes up there--even though I was in my teens when my mom told me that, it still kinda made my privacy feel violated.
posted by PhoBWanKenobi at 9:12 AM on April 23

A few people have mentioned pulleys and buckets. One of my friends when I was a kid had an unconventional one of these: it was a pulley system that ran from the treehouse to the actual house, with a bucket that hung on it. Sort of like the old timey city apartment laundry lines. So you could put stuff in the bucket in the house (actually on the upstairs back porch of the house) and then pulley it over to the treehouse without coming down. Many lunches and snacks were delivered to us this way.
posted by autojack at 9:14 AM on April 23 [4 favorites]

It is imperative that sleep-overs be able to be had in the "club house". This will confirm your girls as the most popular kids on the block. (Roof, good sidewalls, rope ladder).

When they get older, a zip line. This was the first thing we built as boys (at about 8).

Dad built a fort for us when we were kids, not that different from what you're proposing. He made sure of a couple of things for his own peace of mind. He put in vertical supports of 4x4's buried 3-4' into the ground at each corner. He used cedar, and I would too. Pressure-treated lumber isn't safe around kids. PT is too wet to paint in the first year and seeps preservative dust. This can easily transfer to hands and into mouths. He also used pea gravel underneath: it always stays loose. Sand compacts too easily and our cats liked to poop in it. The sand box was off to the side and covered.
posted by bonehead at 9:20 AM on April 23

--tables/benches/bunks that fold old from the walls
--pulleys and ropes
--rope bridge or drawbridge between deck and playhouse
--make a scale model first so the kids can try out a dollhouse-play version and add ideas of their own! also good for rainy days.
posted by rikschell at 9:22 AM on April 23 [1 favorite]

Big, wide window sills (with a little rim, if possible, to reduce the amount of stuff that falls down). Possibly window boxes with plants.
posted by amtho at 9:27 AM on April 23

I love all the ideas everyone posted so far. When I was a kid, my dad built a kid-sized playhouse for my sister and I that was the coolest thing ever. The only trees we had were young-ish Chinese elms and willows (it was a new housing development), so no trees were involved in the building of it, but the coolest things it had were:

1. Kid-sized chairs, tables, and a chaise.
2. A real locking front door.
3. Running water.
4. Electricity -- both indoor and outdoor lights, and an outlet for gadgets and my easy-bake oven.

It was the coolest thing ever, and I wish I had some pictures of it. It was basically a real little house in the backyard of my parent's big house. I'd "run away from home" when my parents were being mean, and go live in the playhouse for a night or two. My sister and I would have sleepovers there, or have lunch, or bake something in the easy-bake and take it in to my parents as a present. When my dad was working in the yard, I'd mow the lawn behind him with a kid-sized lawnmower and clean up in my own little house afterwards, then we'd meet back in the yard for iced tea and sandwiches. I guess the point of all of this is that it's really cool for kids to have a space that's all their own, so any of the ideas above that facilitate that are good ideas. Have fun!
posted by booknerd at 9:33 AM on April 23

Zipline! Definitely.
posted by LarryC at 9:35 AM on April 23

Absolutely a trap door or secret hiding place for goodies. Hooks from the ceiling to hang outdoor lights or an electric lantern from. Maybe a storage bin (non-secret) for holding a sleeping bag or two or blankets?

If you can rig it, maybe a rope ladder they can get up into the fort with as well?

Tire swing!!!!

The sandbox thing is awesome, maybe put monkey bars above it somehow so they can "avoid the sand trap"?

Mini telescope?

The flag idea is really cool. Then the tree fort can become a pirate ship (skull n' crossbones), a castle (lion/sword), etc.
posted by Verdandi at 9:35 AM on April 23

The treeless house my dad built for me as a kid was an a-frame over a sandbox, which might simplify your construction. The front half was an open deck, the back half covered. The low ceiling didn't bother me at the time, but kept adults out. Windows would be more difficult, however.
posted by These Premises Are Alarmed at 9:49 AM on April 23

My older brother and his friends built a treehouse that started out simple enough but gradually turned into a three level thing of awesomeness. From the top level they built stairs and hung ropes that could take you to nearly the top of the tree. So I would suggest multiple levels as an idea.

and now I'm daydreaming of building one for my daughter this summer. So thanks for that.
posted by Sailormom at 9:50 AM on April 23

Hmmm...a recurring theme here (locks, kid sized spaces only) seems to suggest that privacy is a key issue. Is that a correct assumption? I want the girls to have the freedom of their own space, but I don't want to a. be excluded from their play or b. when I do occasionally go into their fort, I don't want to feel like an interloper. How important is it going to be for them to want to get away from me?
posted by ColdChef at 9:56 AM on April 23

Also: what about this: Frigits Refrigerator Marble Runs

Is a large-scale version of the feasible?
posted by ColdChef at 9:59 AM on April 23

nth-ing power (if possible)

suggestion though: leave room to expand the fort/treehouse in the future -- also GREAT idea for stairs, but its kind of a catch-22 depending on what you want to do with it. if its "their place" (your kids) only having a ladder will make it seem more like their secret place. equally, it makes it difficult for adults to get up/down to it. stairs=less "secret/their" place but more accesssible to adults. but def. leave room to expand -- maybe directly in front of the "deck" (towards the perspective of the person looking at the picture)? maybe use screws instead of nails in certain places?

and above all, use some kind of "treated" wood so that it doesnt rot, and if you use nails make sure you check them every few months to make sure they havent worked their way out (this was something that was fun for my brothers and i to do in our treehouse every now and then)

maybe consider a "rack" for things like hats/jackets/etc -- my brothers and i created our own by using nails, but is somewhat dangerous for younger children (we were older than 3 and 5)

treehouse guide is an interesting website, especially this part about the "treehouse year"

are you doing this alone? do you have help?
have you built things before?

sounds like an awesome project, my 2 brothers and i (and friends) spent many a day in our treehouse and its one thing that i will def. be doing for my children when the time comes
posted by knockoutking at 10:00 AM on April 23

How important is it going to be for them to want to get away from me?

VERY important. Doors should be their size and uncomfortable for you to get through. Everything in your house is too big for them so everything in their house needs to be scaled to their size. Plus, when you play Jack and the Beanstalk you will be a more believable giant in relation to a small tree-house. Children definitely need space away from adults (just like adults need space away from kids). It keeps everybody sane and makes the times you all choose to play together much more stress-free.

The marble run is pretty cool, I have seen similar ideas using water and sand as well.
posted by saucysault at 10:03 AM on April 23

re: marble runs

should be pretty easy to re-create using PVC/pipe of some sort -- what would you be using in the marble runs? like golfball sized large-scale? baseball-sized large scale? basketball-sized large scale? also this would probably need to be on a wall of some kind -- maybe create a wall behind the "sandbox" area (so that its in the shade?) and build them on there? have it send the "marble" from the upper level of the treehouse to the bottom (sandbox) level?

also if you do stairs, make sure that they are going to be fairly wide (both from a width perspective - side to side - and a step perspective - depth of each step)

and by "working windows" do you mean glass windows? will this be more of a fort/clubhouse-type area (fully enclosed) or more of a hut? seems like your talking about more of a fort/clubhouse-type room -- if you do this you should consider storage spaces (look at laundry rooms - where there is a counter kind of place + storage above it)

equally is this the kind of thing you are looking to spend some a pretty penny on or just build on a budget?
posted by knockoutking at 10:06 AM on April 23

Water feature. I would look into putting together a piece of PVC pipe (vertically or horizontally) with random holes drilled through, a connection for a hose, and a cap on the other end. Then you have a great oversized sprinkler for the summer.
posted by shinynewnick at 10:06 AM on April 23

If you're considering electricity/lights, keep two things in mind: lights attract bugs, bugs attract spiders.

So, if your kids are freaked out by bugs/spiders, or if you're concerned about them sharing their play-area with an overabundance of spiders, you might want to reconsider that plan.
posted by CKmtl at 10:14 AM on April 23

I don't know your kids but if they're like mine, they're going to love having you play with them. I don't see any good coming out of locks. Kid sized spaces are just neat because as a kid, the whole world is too big for you. But I think an 8x8 "house" is enough of a concession to that. Just put one of those kid kitchens in there, with a little table and chairs -- you probably have that stuff right now anyway. Done and done.

You have several years before you are an interloper, and at that point, BE AN INTERLOPER.
posted by stupidsexyFlanders at 10:16 AM on April 23

Particularly given your climate, I think the aforementioned water feature is an *absolutely excellent* suggestion.

In a similar vein, I'd be inclined to consider a more open-ish structure than the absolute-fortress-of-solitude that kids would otherwise tend to, for purposes of ventilation. When it rains, it's gonna leak anyway (unless you build the honest to goodness shingled roof like my neighbor has).

Some will say (have said) that a privacy place is really cool. As a kid, I was pretty good at zoning out my parents even if I was in the middle of the same room with them, and from a parent perspective, I'm not interested in giving them more places in which to effectively hide from me. I, obviously, am not always the Fun Parent.

Would also have to say I don't care much for sand features. Frequent rain + Sand = Mud. Every time. Don't care what kind of cover you have on it. Again, not the Fun Parent speaking.
posted by LoraxGuy at 10:26 AM on April 23

are you doing this alone? do you have help?
have you built things before?

My skillz are much more in the "designer" category than the "builder" category. I had a family friend and professional carpenter take a look at my sketch this morning and tomorrow he's going to give me an estimate. If it's within my budget, I'm going to have him start right away so the girls will have it by the time they get out for the summer. He'll do all the construction with his team, and I'll paint and hang swings and basically be in their way.

and by "working windows" do you mean glass windows? will this be more of a fort/clubhouse-type area (fully enclosed) or more of a hut? seems like your talking about more of a fort/clubhouse-type room -- if you do this you should consider storage spaces (look at laundry rooms - where there is a counter kind of place + storage above it) equally is this the kind of thing you are looking to spend some a pretty penny on or just build on a budget?

Yeah, glass windows so that there can be comfortable sleepovers. Fully enclosed, but no sheetrock or finished walls. My budget is about what we'd spend for a family vacation this year. Things being how they are...preggo wife, shit economy, job I can't stray too far from right now...I'm thinking of this treehouse as our vacation from reality this year.
posted by ColdChef at 10:31 AM on April 23

Coming from a family with almost no privacy, I would have to say that secrets, especially the little ones, are so important. A hiding place to put something that is theirs and theirs alone is so crucial. Makes them feel terribly smart and grown-up in a very sweet and innocent way.

So I am definitely nthing secret hiding places and locks - even if they're just little easily breakable ones.

BTW - you are an awesome parent.
posted by Sophie1 at 10:43 AM on April 23

What, no steering wheel on the poop deck?
posted by bricoleur at 10:46 AM on April 23

Since all the fun ideas are already taken, I'll suggest a practical one: Make sure the thing can be closed off (i.e., operable door and windows).

My dad built me an awesome tree house when I was a kid, but it didn't have a door. This wasn't an issue for privacy reasons. It WAS an issue because when the tree house wasn't being used by me and my friends, it was being used by neighborhood cats, who found it a safe, convenient, out-of-the-way place to devour their prey. The tree house lost some of its luster after the umpteenth time I climbed up there to discover a decapitated rabbit, or a pile of feathers, or a half-eaten snake.

Or maybe my parents were playing cruel tricks on me. But I'm pretty sure it was cats.
posted by mudpuppie at 10:59 AM on April 23

Yeah, glass windows so that there can be comfortable sleepovers. Fully enclosed, but no sheetrock or finished walls. My budget is about what we'd spend for a family vacation this year. Things being how they are...preggo wife, shit economy, job I can't stray too far from right now...I'm thinking of this treehouse as our vacation from reality this year.

ok good plan there then, just as stated above/before, make SURE it doesnt leak lol or you will have sad kids -- also consider putting in shelving or storage spaces of some kind -- maybe something like this but attached to walls -- if you watch major league baseball think what they store their helmets in in the dugout (does that make sense?) -- and again, if your having an enclosed room have some sort of hook system for coats, hats, etc -- will keep jackets, etc off the ground + much cleaner

keep us updated! looks like a great project!
posted by knockoutking at 11:07 AM on April 23

You definitely need a little door that opens out the top (you can probably get one at home depot or something, the kind of little hinged square door you see on the roofs of lots of office buildings and whatnot.

This door must give you access to some sort of small platform mounted higher up in the tree, not enclosed, and supported by the tree.
posted by floam at 11:11 AM on April 23

A lockable door that's not really lockable would be neat too. The illusion of privacy is wonderful for these little secret bases. Maybe a bathroom doorknob that unlocks when you shove anything inside the hole? Also, maybe "accidentally" leave a floorboard loose or something similar that can be discovered by the genius little devils.
posted by floam at 11:14 AM on April 23

I had a tree house for a few years that I know think was engineered to fool kids into being observed. The door was in the rear so you felt like you were hidden from the house when you entered, and the two large windows looked out on the yard and the house. This also meant that any occupants could be observed by someone working the yard or someone in the kitchen. We never really caught on to that though.

Also, you don't seem like you're going overboard on safety, but the one thing you should do is keep every extra blanket, sheet, and sleeping bag in the house under lock and key. If you don't one of your kids, or a neighbor's kid will fancy themselves a parachutist and continually leap from the highest point (they'll get up there somehow) until I got they get hurt. That's not really a bad thing, but it will happen.
posted by Science! at 11:27 AM on April 23

If you're going to have glazed windows consider using laminated glass. That way when a window gets broken it doesn't leave wrist slitting shards in the frame or foot piercing shards on the floor/ground. You can go with an UV stabilized acrylic too but it'll eventually get all scratched up. Alternatively just screen the openings and have a simple solid shutter that you can close to keep the wind out.

I'd add some kind of window in the roof. If you go with shingles you can buy clear vents. For a corrugated roof you can buy translucent fibreglass or clear polycarbonate panels to match. If it's a simple tarp then light colours let in a lot of light.

If you use wood decking instead of a solid surface in the house dirt will fall through.

LoraxGuy writes "Frequent rain + Sand = Mud. Every time. Don't care what kind of cover you have on it."

A washed masonry sand won't form mud. You've got to line the bottom of the sand box so dirt (with it's clay and organics) doesn't come up from the bottom but otherwise you shouldn't get mud. You can get this way cheaper at a gravel pit than you can buy "play" sand at the hardware store. And if it does become contaminated you can use it on your lawn to fill the holes after aeration.
posted by Mitheral at 11:33 AM on April 23

Hydrophobic sand. It won't make mud at the bottom of a lake.
posted by floam at 12:01 PM on April 23

A "dumbwaiter". Basically a bucket on a rope for hauling stuff up into the treehouse. This is fun, and also subtly increases safety as they can use it to bring things up and have two hands free for the ladder.
Will glass windows make it a hot little greenhouse? That might cause heatstroke, maybe worth considering given how hot a sealed car can get.
I would have loooved a secret trapdoor space when I was a kid.
A little cupboard/cubby for each kid, with a personalized front and some sort of lock (maybe an easy combination lock, and the numbers kept safe with the adults for the inevitable forgetting).
A height chart
A tin-can phone down to ground level. Even cooler, a speaking tube!
Some sort of observation area for bugs
A blackboard wall inside, large enough to trace their full bodies on if possible
A birdfeeder they can refill themselves. Do you get hummingbirds? That'd be fun.
A chest with dressup clothes & disguises.

You're a nice dad!
posted by pseudostrabismus at 12:01 PM on April 23 [4 favorites]

Depending on the size of your windows, it might get a bit dark in there, so you could try no electricity needed lighting.

You are an awesome Dad!
posted by arcticseal at 12:03 PM on April 23 [1 favorite]

Love that you are doing this for your girls. They are going to have a ball!

Glass windows sound expensive and could actually make it hotter inside the treehouse--maybe screens, as someone above suggested, would work bettter?

Nthing secret space in the floor.

Half wall inside with kitchen curtains above it for pretend-play (becomes a theater, tv set, puppet show stage, kitchen pass-thru, even a changing area for dress up).

Big trunk for dress-up clothes, as they get older can be used to store other treasures, books, toys, etc.
posted by misha at 12:25 PM on April 23

Excellent suggestions. Thank you all. FWIW, this was my childhood treehouse. I'll keep you updated as this project continues.
posted by ColdChef at 1:06 PM on April 23 [3 favorites]

The playhouse that I had as a kid had screened windows with these large flat shutters that attached at the top, no glass. When you wanted to open up the place, you propped open the shutters with the attached rods, making a kind of awning. This was a good design for several reasons. It was cheap, it creating a kind of rain/sun awning when open, was very effective in keeping out the elements when closed, and it prevented solar heat gain you get with glass.

Make sure that you have a plan to get rid of the solar heat gain with some venting under the eaves. Unless it is in some heavy shade, those small spaces can get incredibly hot!
posted by Foam Pants at 1:41 PM on April 23

You can start with a box on stilts with a ladder and add on. I'd keep it just big enough for 3 - 4 kids to lie down. You can add amenities every year to keep it fun. A

Lumber comes in standard lengths, and it will be cheaper if you don't have much waste. Mosquito netting will make sleepovers more pleasant. Personally, I wouldn't add electricity; battery operated lanterns are fun. Ask friends for any old sheer curtains; they make good mosquito net/ stage drapes /tent.

Ask the kids what a tree fort should have. We built a custom play structure for my son, and his biggest wish was a tire swing
posted by theora55 at 1:54 PM on April 23

Sun Jar
posted by twistofrhyme at 2:17 PM on April 23

RE: windows, I would recommend going to a building salvage type place and getting some old single-pane double-hung windows (you know, the kind that all the people are buying and hanging on the wall of their living room nowadays) -- easy to plug into a hole, cheap, and with that old-timey feel. no point in getting any fancier than that, especially if there is no drywall or insulation
posted by misterbrandt at 4:08 PM on April 23

I love the idea of a chalkboard wall. I think you can also get paint that is magnetic -- here's a quick article I turned up: http://interiordecorating.suite101.com/article.cfm/use_magnetic_and_chalkboard_paints. Then you could do the magnet/marble thing AND have an artspace. (By the way, love that fridge marble thing and may need it for myself -- who says kids have all the fun?)

I also think it's really important for kids to have their own space that is also a safe space. However, if you size things too small then they won't be able to grow into it, I would think. I guess that depends on how many years you think they might be there.

How about a star map and a mounted "telescope?" It doesn't have to be a real telescope -- pvc pipe mounted on a swivel would work. Maybe this could double as the phone to the ground level -- take off a piece and you have a telescope, put it back on and it reaches to the ground. Hmmm... this could also be used in a periscope function?

I really do like the idea of you doing the framework and then letting them go at it. Collect scraps and leave them in the yard to construct what they want. Show them how to hammer things together. Obviously, they'll want help from time to time but who knows what a kid could come up with!
posted by amanda at 4:33 PM on April 23

Crow's nest/observation tower?

I used to have a friend with a fort in her backyard that was really high up and surrounded by pines. You could look out over the whole neighborhood from inside it, so it became really useful for games of hide and seek. You don't necessarily have to build the same thing, but a single-person lookout post a little taller than the rest of the fort makes the fort feel extra special.
posted by Demogorgon at 5:20 PM on April 23

Zip line. Zip line. Zip line.
posted by zardoz at 12:11 AM on April 24

We had two kids break their arms within an hour of one another on our zipline. Just a data point for ya.

Also, don't forget the rope climbing-webbing. Or the faux rockwall. (don't pay $360 for a rock wall, it's an easy DIY that the kids can even help out with. You put up the slant board and cut up little pieces of wood, they nail them on there willy-nilly, and then when they go away you screw them in tight)
posted by stupidsexyFlanders at 3:21 AM on April 24

Make sure the sandbox has a cover or neighborhood cats will poop in it. Also, when I was a kid, what I wanted most in my imaginary treehouse were real curtains for the windows (I was an indoorsy child). Made of some sort of checked-gingham fabric. Your girls may want something else - ask them!
posted by mai at 8:56 AM on April 24

I'd like to thank everyone for their interest and participation in this thread. Yesterday was a day full of excitement and imagination as I planned out this dream house. Sadly, I got a terrible wakeup call today. After speaking to the carpenter who came by to look at the property and give me an estimate, the materials alone that would be required for this project are almost twice what I believed the entire job would cost. His estimate was $4000 just for the materials and then another $5000 for two weeks of labor to construct it. This confirms my belief that I have no idea how much things cost these days. There are probably ways to bring that figure down, but I don't want to make the project lame and unsafe just to be cheap.

This does not mean that this project is dead, but I'm going to have to drastically rethink it. I have no building skills whatsoever, but I'm going to hit the local library next week to see how hard it would be for me to learn how to be a handy man. Rather than throw out the idea of a treehouse, I'm going to have to wait until I can financially or physically do the job myself. This may mean that my baby on the way will have a treehouse by college.

Again, thanks for all of your suggestions. In my dreams I have the coolest treehouse ever. And, hey, now I have a goal for next year.
posted by ColdChef at 2:31 PM on April 24

I am not super handy but building a deck is not too difficult. Half the battle is owning/renting the best quality tools. I would be happy to help you build the treehouse during the NO meetup. Many hands make light work etc. Maybe the price could be brought down by not using cedar wood for the clubhouse itself.
posted by saucysault at 4:37 PM on April 24

That's a very kind and generous offer and I'll definitely keep it in mind for later.
posted by ColdChef at 4:43 PM on April 24

You will find a ton of great books at the library on doing projects like a treehouse -- look for ones on building decks, sheds and treehouses. Look for the Taunton series -- I think they are really good. Also, some of the Fine Homebuilding series are also good. They will give you a good sense of what you can do yourself, where you can skimp on wood and maybe where you cannot. And also give you a lot more ideas.
posted by amanda at 5:47 PM on April 24

I wouldn't be able to attend in NO, but a good old-fashioned treefort raisin' sounds like a great meetup concept. Host supplies plans and materials, everybody brings tunes, beers, skilsaws and skills.
posted by stupidsexyFlanders at 7:41 PM on April 24 [1 favorite]

also, since you're scaling back the plans, here's a pretty basic one I built a couple of years ago for around $500 lumber. You can still add cool stuff to this model ;)
posted by stupidsexyFlanders at 7:46 PM on April 24