Garnier Limbs

• Garnier Limb Weight Rating
• Cost Of Garnier Limbs
• Can I do it Myself?

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How to Install a Garnier Limb

Installation of garnier limbs and other treehouse fasteners requires the right tools, careful alignment, and some combination of brute strength and leverage. Read carefully and prepare yourself before trying to install a garnier limb. It may take a week or two to acquire the proper drill bits or the right size wrench.

Ultimately, you probably want the floor of your treehouse to be level. Not always true, but usually so. The first step, before picking up the drill, is to level around to each spot where you will install a garnier limb or other treehouse fastener. If you mark the center of each hole with a small nail or screw, then it will hold the spot and allow you to double check after all holes are marked.

Leveling may be as simple as grabbing a 4' or 8' level and marking. But with tree houses, it usually isn't. You almost always have to level two points that do not have a direct path for a straight edge level. The best method for leveling treehouse support points is with a water level. You can buy one, or make one with a length of tubing filled with water. If it worked for the ancient Egyptians, then it's good enough for us. Fill the tube with water, make sure no air bubbles are in the line, and have one person stay put and the other take the other end around to mark all other points. Then cross-check until you are confident that everything is right.

Don't forget to make adjustments for different thicknesses of treehouse fasteners, the brackets that fit on them, and the sizes of beams that they're supporting. For example, if you have a 3x8 beam on one side, and a 3x12 beam on the other, they you will have to adjust by about 4".

When drilling for smaller treehouse fasteners like large lag bolts, the methods are the same as for any other lag bolt. Choose a ship auger style drill bit that is the same size as the shank less the threads. You want the threads to bite into the wood, but not to force a solid shank into a hole that's too small.

When drilling for garnier limbs, there are a few different methods that professional tree house builders use. Since garnier limbs require 2-3 different diameter holes of different depths, drilling is a multi-step process. First, you drill out the depth that you will recess the collar into the tree with a 3" (for standard size GLs) holesaw bit or better yet, a self-feeding timber bit. Then, you chase it with a long ship auger somewhere between 1" and 1.125" diameter. When installing in a softwood tree species, use the smaller hole for the ship auger. If drilling a third diameter hole for the thinner shank on the interior of the collar (something not all professional builders do), then drill with a 1.125" - 1.1875" bit to the appropriate depth.

Alternatively, for garnier limbs, a one step drill bit does exist, but it has mixed reviews from treehouse builders. It is essentially all three of the above steps combined into one bit. The advantages are that it lines up all the holes for you and gets the depths right. The disadvantages are that it doesn't clear well, it doesn't self-feed well, they are expensive, and they break easily.

This is the part where the brute strength and leverage come in. Garnier limbs have to be installed very tightly into the tree or they will not work and will cause the tree unnecessary harm in the process of not working. As a result, they require a lot of force to turn them in.

With how much force it takes to turn a garnier limb into a tree, you wouldn't think they would ever come out. But just in case, some treehouse builders will use gorilla glue or epoxy on the threads before or during installation. Don't worry, if installed properly, they're not coming out!

The most common tool used is a long handled pipe wrench. Forget the 12-18" ones, you need more leverage. Some treehouse builders install garnier limbs with 3' pipe wrenches, or an 18" one with a 2' pipe on the end. Better to use the right length tool to minimize the risk of multiple parts falling while working in trees. The pipe wrench does damage the paint and create marks in the shank/perch of the garnier limb, but these marks can be cleaned up with a grinder and spray paint afterward.

Another option that a few treehouse builders have used is a 3/4" socket wrench, with a 1 7/8" socket (for standard sized GLs). The advantage is that the ratcheting action make the installation faster. The disadvantage is that turning the garnier limb in by the nut can make the nut difficult to remove later, if necessary.

Some of you may have thought of getting a large air compressor and an impact wrench to turn a garnier limb in. While theoretically possible, it has been tried, to no avail. It simply takes too much torque to install garnier limbs in trees.