Building a treehouse in the redwood grove of a neighbor (pics included)

Tony Hwang wrote, on Sat, 20 Sep 2014 18:45:55 -0600:

Yeah. This is hill country. We rope down thousands of feet on a "normal" hike, so, yeah, we all have climbing equipment.

In fact, you can see the harnesses everyone has on in the photo below:

It's deceptive, but that is a very steep slope, so, what's 10 feet on one side of the trees is about twice or thrice that on the other side.

Arfa Daily wrote, on Sun, 21 Sep 2014 02:21:40 +0100:

Ours are really nice! They span 100 feet from tree to tree, and they are equipped with 120VAC and WiFi, with deck chairs and a fridge for the booze, and we often leave a spare laptop in the treehouse for visitors.

Arfa Daily wrote, on Sun, 21 Sep 2014 02:21:40 +0100:

Kids build suspension bridges on parabolas. Adults do it with the catenary!

Very cool so far, thanks for sharing, and please keep us updated.

Have you seen the tree house show on TV?

Leon wrote, on Sun, 21 Sep 2014 08:05:23 -0500:

No, I haven't seen that show, but, I realized belatedly I had not snapped photos of the construction of our last treehouse a thousand feet into the woods, so, I'll snap a few when I get the chance and append them.

Living in hilly country, we get pretty good at doing things at height and distance.

At that older treehouse for example, we recently added WiFi, which is no small feat considering it's a thousand feet or more from the nearest house, so the problem of electricity needed to be solved (they used solar panels but I wasn't part of that setup).

Here, for example, are the wireless speeds I got earlier today, which aren't bad, considering there are no wires (26ms, 9 Mbps, 12 Mbps).

Oren wrote, on Sun, 21 Sep 2014 09:18:46 -0700:

Not my dog, but she's a pointer of some sort because it kept pointing at animals in the woods, and the guys were talking about how good it was at what it does.

It's the neighbor's dog, so that's all I know, other than I bring steak bones every time I see it because it loves it and I'd have to compost or throw them away anyway.

How are you attaching the structure to the trees. I live in the Redwood Country and have been involved with Tree House design. I do know there are fasteners used to attach structural elements. I would like to see the actual tree house. john

Just thought I'd share with you guys some pics of the treehouse in the redwoods my neighbor asked me to help him start this weekend:

Here's a shot of the ladders we strapped to the redwood trees:

This shows one of the neighbors helping anchor the cargo netting:

It's a good thing she did, as she was the first to test it out:

Here you can see the 1/2" steel cable for the suspension bridge:

We made a *lot* of mistakes already, but, we are working together, and, in the end, we'll have a nice catenary suspension bridge and a treehouse suspended in between the redwoods with nothing but air beneath it.

We built one 15 years ago, in a small redwood grove in San Mateo.

We built a triangular structure between three trees. We used two 2x12's between each pair of trees, clamping them to the trees with threaded rod. No fasteners were embedded in the trees. As the trees grew, over time, we'd release a bit of tension on the allthread as the trunks grew in diameter.

Supported by those 2x12's (6 total) was a standard 2x6 joist floor and 7 foot studwalls with a standard pre-hung entry door on one side. There was about six to seven feet between the trees.

Bob F wrote, on Mon, 22 Sep 2014 08:34:07 -0700:

The neighbor is using expensive "tree bolts". These are something like $25 each, or so I'm told. They allow the redwood tree to grow. Even the cable, as it wraps around the tree, is offset from the tree by a set of two-by-fours.

I should have snapped pictures of all the equipment as it seems some of you have good experience which we can use as nobody wants to hurt the trees.

I will try to snap some photos next time I'm there to help out.

Just to update this thread, we completed the 250 feet of steel cabling today by lashing the two ends together using these cable clamps:

To keep the cables from cutting into the trees, and to allow the trees to grow outward, we put up a series of these wooden standoff blocks:

You'll notice that we doubled the cables as they wrapped around the trees so that the strength is always two time 14,000 pounds, at all times:

Here, you can see the two cables, hanging as two catenaries, from which we will hand the suspension bridge:

We're starting to get used to working in the heights, as you can see by this photo of my neighbor coming down from disentangling the lines:

As you can imagine, we wear harnesses and we have static lines hanging from all the trees, as you'd be amazed how many times you need them:

In fact, my unenviable job today was to stand at the TOP of this ladder and position the cables, which I did with two hands on the cables so I had to be wearing a harness or I would have fallen off in no time:

I'll let you know when we drill the redwoods to put in the tree bolts, which will anchor the house; but first, we're working on the suspension bridge (you can see our cargo netting in some of the pictures above).

Tomorrow we're putting up WiFi on a neighbor's roof, so we wont' be working on the treehouse until next week.

If you installed these without lock washers I would recommend you go back up and at least put nylock nuts as safety nuts. Heating and cooling will cause those nuts to walk off the u-bolts.

I hate ladders like these, seen the two by's pull off after a short while especially if your shouldering a load going up or down. The rungs should be in notches.

Hope no one or nothing falls.

OFWW wrote, on Sat, 27 Sep 2014 23:55:45 -0700:

Thank you for that safety suggestion! That is a good point. Safety is paramount.

This treehouse 50 feet in the air in the redwoods has to outlast us and it has be safe at all times.

Since we didn't use lock washers on the steel clamps, I will advise my neighbor and I will snap a picture of the results for you.

You will notice that we doubled up the two ends of the steel cable as they wrapped around the tree, so that we'd always have two cables supporting the bridge.

On the big tree, 125 feet away, we will add a wraparound additional steel cable, so that the middle also has two cables.

Any other safety ideas are welcome, as we're just at the point now where we can start hanging the suspension bridge from the two steel catenaries.

For example, you will notice that we followed the rule as shown here:

Following that diagram, we put the "saddle" of the clamps on the "live end" (the mnemonic we used was "don't saddle a dead horse").

Any other tips are welcome, as we're just now at the stage where we have the ability to build the 125 foot long bridge starting about 15 feet up in a pine, and then going straight across a steep slope through the set of two redwoods, and then on to the really big redwood 125 feet down the slope.

The treehouse will be in the middle of the bridge.

OFWW wrote, on Sat, 27 Sep 2014 23:55:45 -0700:

This is a good point.

We have so many ladders, most of which are roped end-to-end to the trees for height, that we just made them as simply as we could.

You can see that we have cargo netting, to allow us to cross from tree to tree once we climb up the ladders:

But, we also usually wear safety harnesses and ascenders whenever we work more than 15 or 20 feet up (which is almost always since it's a steep slope so what is 15 feet up at the uphill end of the cables is something like 50 or 70 feet up at the downhill end.

On 9/28/2014 9:50 AM, Danny D. wrote: ... snip

... snip

Are you saying that the tree house will be in the middle of a 125 foot suspension bridge. How much will the tree house weigh when fully loaded and do you have any idea of the forces that may be in the cables?

Dan

dpb wrote, on Sun, 28 Sep 2014 13:54:02 -0500:

They *are* designed for this purpose, are they not?

They didn't come with lock washers.

I'm sure we have nothing against putting them on; but, if they really needed lock washers, wouldn't they have come with them?

Dan Coby wrote, on Sun, 28 Sep 2014 12:34:27 -0700:

The tree house will be where our cargo net currently is.

That's roughly half way from the uphill pine to the downhill big redwood (with two little redwoods, side by side, in between).

The steel cables can handle 14,000 pounds each.

That's 28,000 pounds (because we maintain a double cable throughout).

We don't know how much the bridge & treehouse will weigh, but if it's close to or greater than 28,000 pounds, then we have a problem.

How much do you think a treehouse will weigh?

Oren wrote, on Sun, 28 Sep 2014 14:21:31 -0700:

Yup. 45 foot pounds. Thanks.

I'm relaying all this information to the neighbor as I'm just a helping hand. I jokingly refer to myself as the "union worker" because I make jokes about OSHA getting on their case every time I have to climb one of those ladders!

I do apologize that updates are slow, as I can't snap a picture unless I'm there, and the treehouse is only worked on during the weekends, and I'm not always there to help, but I will try to snap pictures as we progress.

Dunno if I should append all to the same thread, as the way "I" read this newsgroup is that I only look at the threads from the last day or three. Dunno how others look at older threads, 'cuz this could take a few months elapsed time.

You also have to consider the geometry of what you are creating. If you are tensioning the cables for very little sag then the forces in the cable can be many time the weight of the tree house. Without knowing exactly what you are creating then I cannot guess. That is why I asked if you had any ideas of the forces in the cable.

I do not know what you are planning upon building. That was why I asked you. If you are talking about the tree houses that we built as kids with a plywood floor and a few boards and a tar paper roof then only a couple of hundred pounds. If you are talking about some of the multi story creations that I have seen on TV then many tons.

Dan

Dan Coby wrote, on Sun, 28 Sep 2014 20:32:48 -0700:

We "tensioned" the cables, by hand.

What we literally did was put a broomstick through the 60 pound wooden spool of 250 feet of 3/8" steel cable and we mounted that on two chairs about 15 feet downhill of a big pine tree.

Then we went uphill to that pine tree at a point about 15 feet off the ground and then back to the chairs with the spool of wire.

At that point, we tied a rope to the end of the wire, and we walked the wire downhill a little less than about 100 feet to a big redwood.

At that redwood, we climbed up to the same height as the pine (which, since it's downhill, is about 40 or so feet up in the air) and we pulled the rope with the wire cable attached.

Then we pulled the rope which pulled the cable back up the hill back to the point on the path 15 feet below the pine, where we pulled it tight by hand, and then clamped the 8 clamps on.

Then, we simply slid the cable around the big redwood and slid it around the pine, until the cable clamps were symmetric around the pine, as shown in the last set of pictures.

I won't mention the fact that we accidentally crossed the cables because we went around the big redwood the wrong way, as that's embarrassing to mention. Nor will I mention how many times we got hung up in the branches between trees, necessitating mid-air precarious surgery on the trees.

Given all that, I wouldn't call the tension all that tight. You can see the sag in the photos. Maybe it sags, oh, I don't know, about 5 to 10 feet maybe?

I think we're talking just a plywood box, with a deck. I should mention that there will be anchors on the two little redwoods, so, the treehouse won't actually be floating on all sides. The bridge *will* be floating though. It should be fun once it's done and wired for Internet. It has a great view once you're up in the redwoods.