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As planned, material delivery day. The last of the materials needed for the foundation phase reached the site today. By reached, I mean two trailers parked in the driveway. From there, the gentlest path to the treehouse site about 150 feet away was by foot. Everything was sorted, checked and stacked, placing the first-needed materials closest to the tree. The Douglas fir was shipped green, so a drying stack was set up to allow the wood to breathe.
Materials are stacked and sorted at the Ithaca treehouse site.
A few word on the Dougies. Douglas fir isn’t a local wood here in the Northeast, and it’s not a classic hardwood used for decks. I found it at a local lumberyard, unwanted among the more familiar spruce-pine-fir building wood common here. Still, as anyone who’s spent some time out West can attest, Douglas fir is a gorgeous wood. Strong, fast growing, harvested from managed forest, with a beautiful rosy red and gold hue, and a slight citrus scent. For a builder it’s also dimensionally stable, meaning it doesn’t shrink, twist or check much as it dries. With a light coat of a soy-based water sealer, it will make a very pretty deck surface, fit in well with the slightly rustic feel of this treehouse and stand up well over time. Pleasing to the eyes, and much easier on the environment than pressure treated decking or hardwoods shipped from the Amazon basin.
One last note: Michael Garnier comes through. I talked to Michael on Monday and explained the situation regarding the need to extend his namesake Garnier limb tree anchor bolts to allow our wide black locust beams to fit alongside two leaning trunks. He explained the solution, had the needed part and is shipping it out as I write. For a guy who pioneered the modern treehouse movement and could easily carry the ego to go with that distinction, Michael is always a pleasure to deal with. No pretenses; just ready help and smart solutions. And if you haven’t seen his Out-N-About Treesort (www.treehouses.com) you haven’t seen the spirit of this art form at its best. Waiting for the parts to come from Michael’s place in Oregon might delay the beam raising a few days, but doing it right trumps doing it now when questions of strength and safety are in play. Also, there’s plenty of on-the-ground prep work before the beams go up, all of which can be done while the U.S. Postal Service does its stuff.
Today will be spent making the final purchases of supplies for the foundation phase. We decided to use some pressure treated southern yellow pine lumber in one part of the foundation – the joist structure below the deck. The good news is that SYP lumber is harvested from carefully managed forests where replanting exceeds harvest, and it’s a relatively strong and light wood. It’s also true that the anti-rot chemicals squeezed into the wood today are much safer than just a few years ago.
In this case two factors lead to the decision.
First, the only viable alternative at hand was locally milled black locust lumber. We invested in black locust for the main beams because of its natural rot resistance and its incredible strength. That was an easier choice, because the alternative was either multiple pressure treated 2×12s or engineered beams such as Glulam. Both options can be heavy and carry their own tall price tag. Black locust proved to be a middle ground on cost, and a local mill that specializes in the wood (Locust Lumber Co.) was only a few miles from the job site. The weight gain for the beams was minimal – just a few hundred pounds for a project rated in the thousands – and the cost was acceptable. Using black locust to replace SYP as joists, however, would have added 25-30 percent to the cost of this phase and would have doubled the weight.
The second reason was exposure, or lack thereof. The decking above will be exterior grade plywood inside the treehouse and Douglas fir for the exposed portion, so no one will be handling the treated SYP joists (other than me when the platform is built). Since most risks from previous types of treated lumber are tied to repeated handling, it was decided any exposure risk was very minimal, and the cost and weight savings were significant enough to use justify the choice.
These final foundation phase materials should be delivered Monday. From there, it’s all just getting it up into the tree.
For those following along, no luck getting Michael Garnier on Friday. He was traveling. I’ll try him again Monday and see if we can work out the Garnier limb extension question.
The family plans a yard-cleanup weekend, so no work on the site. The area had three major ice storms in March and there’s lots of significant tree damage on the 2.3-acre lot. None to the two trees that will be part of this project, but still the chainsaws and rakes and wheelbarrows will be humming. Monday will be a material delivery and stacking day. I’m aiming for Tuesday as the day to lift some beams up into the tree, before I shift to my other active job site about 30 miles from here in a town called Horseheads.
No, I didn’t make that name up.
At 7:02 a.m. the digital thermometer was above the dreaded freezing line, so we were on for setting Garnier limbs.
Installing a Garnier limb treehouse anchor requires patience, a steady hand, and a large pipe wrench.
Rick’s Rental World had the right-angle Makita drill ready when I got there, and the custom bit started spinning shortly after 9. Five of the eight Garnier limbs had to be installed from ladder top, so there was some rigging needed between each installation. First the ladder had to be secured to the tree, so I didn’t have to worry about it pushing away from the tree as I leaned in on the drill or sliding sideways as I turned the 24-inch pipe wrench needed to set the GLs. I had to be strapped to the tree as well. When you’re off the ground, it’s hard to get the footing needed to control a powerful drill and steer it squarely into a healthy tree. With the strap in place, all moved forward.
For the pure tree lover, this is the hardest day of the project. If we do everything right, this will be the only time we knowingly damage our host. There’s no denying it, building in a tree is not a painless process for the home team. That’s why proper engineering, the right equipment and careful procedures are key. Keep all harm to a minimum and be sure not to overwhelm the tree, and it is more than capable of handling anything we toss its way. Compared to the loads and forces with which nature challenges an adult tree, a properly designed treehouse is, at best, a temporary burden easily compensated for as the healthy tree continues to grow. Add to that the love and dedication most host trees get from the families that find their peace among the branches, and we get as near to a symbiotic relationship as possible.
Other than the anticipated beating I took from that powerful mule of a drill, all went exceptionally well on GL day. Eight GLs – four with the standard 1-inch-thick collar and four with the heavy-duty 3-inch-thick midsection – were all set by 3:30 p.m. Levels look good, and I hit nothing but good healthy wood when drilling the holes. That means the odds are great that the tree will handle the intrusion and the load, and all will go well from here.
In two places the GLs 6-inch outer load-bearing shaft is not wide enough to carry the 5-inch-wide black locust timbers due to the lean of the trunk right above the GL. The solution is to extend the GL, and back up the longer GL with a cable anchored a few feet above. This actually makes for a much stronger foundation, and the cable back-ups were called for by treehouse engineer Charley Greenwood. I’ll contact treehouse guru Michael Garnier. His Out-n-About Treesort uses extended GLs and cable in many of its designs, and I’m confident he’ll have the parts we need.
When the rain comes …
Although the sun jumped through at times, the site spent most of the week getting soaked. Temperatures were above freezing, but ice on the limbs and ladders as well as the unwise collision of wet weather and power drills kept things quiet on the site.
In the meantime, work moved forward locking down suppliers for some of the later phases of the work. Whenever possible, I try to deal with local lumber mills and other businesses. Keeping a dollar local promotes hometown businesses, and the benefits of that philosophy are many. Finding materials from the work region also helps keep the carbon footprint of any project down by limiting the amount of fuel that goes into transporting materials to the area. Of course, you have the balance any gain from this against the materials themselves, the process that produces them and the overall cost to the project. In the end there is judgment and there are choices, but at least we’re learning to ask the right questions.
One great local business I’m working with is Rick’s Rental World in Ithaca. It’s a little off the beaten path, but the service is excellent and they somehow seem to have everything from hydraulic booms to wedding supplies. I’m taking a bet on a favorable weather forecast and will be at Rick’s counter 8 a.m. Thursday to pick up a high-torque Makita drill for the day. If Mother Nature sees fit, it’s time to set the Garnier limbs.
