Is My Tree Strong Enough For A Swing?

Is My Tree Strong Enough For A Swing?

Too many times I've seen trees crack because someone didn't take the time to make sure their tree was strong enough for a swing. You should be sure your tree will work with the load your swing will put on it.

Is my tree strong enough for a swing? Your tree should be at least 8" in diameter to be strong enough for a swing. The branch you are going to use for the swing must be health. You can test it by putting a rope over the spot where you want to place the swing. First, pull down gently to see how the branch responds. Once it has passed the gentle pulling test, you will need to put a load on it equivalent to the maximum weight of the swing with a rider.

What kind of tree is best for a swing

Different species of trees have different hardness levels. You want the tree you use for your swing to be a hard species.

Hardword trees in North America that would be good for a swing:

  • Oak
  • Maple
  • Beech
  • Hickory
  • Ash
  • Sycamore

Softwood trees in North America potentially safe to place a swing on:

  • Cedar

Softwood trees in North America to avoid placing a swing on:

  • Pine
  • Fir
  • Willow
  • Poplar

In addition to the hardness of the tree, you also need to consider the overall condition of the tree. You should inspect the tree to see if it has any rot or hollowing occurring on the outside or inside of it.

You also should look for termite damage. Termites can infest a tree, in some cases, going relatively undetected.

Hitting the tree with a hammer or other object can help you see if some areas are weak under the bark. The hammering can also help you hear if there is any hollowing going on inside the tree. Just be carefull not to hit it too hard and damage the healthy parts of the tree.

You also need to look for cracks or splitting in the tree. Particularly, you need to investigate the limb you will use to hang your swing from and the area of the tree around that limb. You should take care to look all the way around the limb for damage.

You can test the limb for decay or weaknesses by placing a rope around the limb where you want to hang your swing. Start by gently pulling on the rope to see how strong the limb is under a light load. Once the limb passes the first test, continue to test the limb by gradually increasing the load on it to see how it performs. Your final test should be to place a load equal to the swing and the maximum weight of a rider. I would suggest going a little above the max weight just to be sure.

When a load is placed on the limb, it should keep its general composure. There will be some bending, but it should not look as if the branch is going to break off.

What kind of rope should I use

When selecting a rope you need to consider its strength, stretch, performance when wet, and UV resistance. Secondarily, you will want to consider the cost.

Taking all of these factors into consideration, polypropylene and polyester ropes are your best choices. Both are strong, UV resistance, and hold up well in wet environments. They are also available at relatively low prices.

Polyester is preferred over polypropylene for longevity. Polypropylene has a lower UV resistance than polyester.

If cost is not an issue, Dyneema cord would also be a good choice.

Below is a list of ropes that will work for swings:

  • Polypropylene
  • Polyester
  • Hemp
  • Hempex (synthetic hemp)
  • Manilla
  • Dyneema cord

To get some free rope you may try going down to a climbing facility and seeing if they have rope that they throw out when they replace it with new rope. If you live near a port or harbor, you can try going down there and seeing if the boats discard rope that they have replaced.

Also, keep in mind that some ropes are slippery than others. You can make up for the slipperiness by putting knots in the rope for gripping. But, knots weaken the strength of the rope. So, be sure to compensate for the knot weakening by increasing the size of the rope you use.

How much weight can a tree branch hold

You really can't tell how much weight a tree branch can hold by looking at it. You should do a load test before using a tree branch to support anything; including a swing. A tree branch that is at least 8" inches in diameter should be able to support a swing with a rider, but you should still test it.

What should be under my tree swing for safety

What is under your swing is just as important as what your swing is made out of and how it is hung. Spend an ample amount of time preparing your ground cover to ensure the safety of your riders.

Before you put any ground cover under your swing, be sure to check for objects that may injury a rider when they're swinging or getting off the swing. Check for debris, such as, broken limbs, glass, rocks, cans, and other similar items that could hurt someone. Also, look for tree roots that may be hidden under the grass.

It is best to cut the grass and prepare the ground under the swing and beyond the perimeter of the swing. You should do this because someone may fall off of the swing while they are up in the air. This could throw them beyond the point of where your swing ends its amplitude. If you haven't prepared the ground correctly beyond your swings perimeter, they could be seriously injured. I would recommend clearing and preparing the ground an additional 10 to 20 feet beyond the swings perimeter.

After you have cleared the area, you have to make sure the ground in padded enough for a rider that may fall off. Now, I know most of us don't think we will fall off of a swing. But that is exactly what the people that fell off thought before they fell off. So, take this part of you swing design very seriously. It could be the difference between walking away from a fall and serious injury.

Here is a list of the best things to place under your swing for safety:

  • Pea gravel
  • Rubber mats
  • Rubber multch
  • Sand
  • Engineered Wood Fiber (EWF)
  • Artificial grass
  • Natural grass

Pea gravel is made up of small smooth stones. It is shock absorbent and resistant to microbial organism growth.

Rubber mats are made from recycled rubber. They use a pinning system that makes it easier to install.

Rubber mulch is made from recycled tires. This material is highly durable. It can last for up to 50 years.

Sand should be rounded sand particles. This is known as playground sand. It is best not to put a border around the sand. You should let it be free flowing so that it displaces propertly when impacted. Putting the sand inside a box can cause it to not give when someone lands in it. This could cause serious injury.

Engineered Wood Fiber (EWF) is made from fractured wood. It has to be checked and re-leveled often. It is suggested that you put rubber wear mats under EWF so there is sufficient protection when the EWF is displaced.

Artificial grass is made of polyethylene or nylon. It comes in rolls or tiles. It is made to look like real grass.

Natural grass, to some, is the best choice for safety under your swing. The best types of natural grass to use are bermuda grass, Kentucky bluegrass, and rye grass. The best thing about natural grass is that it is natural. You don't have to worry about what it is made out of and if it will affect your family's health.

How do I attach the swing to my tree

There are two ways you can attach a swing to your tree. You can put eye bolts through the branch and attach the rope to them, or put the rope over the branch and tie it to itself.

Eye bolts

First, from what I understand, you should use a shoulder eye bolt, not a plain eye bolt. Shoulder eye bolts are rated for angular loads up to a 45 degree angle. Plain eye bolts are only rated for vertical loads. You should consult a shoulder eye bolt chart to decide which size to use for hanging your swing. A 5/8" shoulder eye bolt from Cleveland City Forge is rated for 1000 pounds at a 45 degree angle.

The eyebolt should be made of either galvanized steel or stainless steel so that it will not corrode easily outdoors. The eye bolt also needs to be longer than the diameter (thickness) of the branch so you can place a washer and nut on the end once it has been screwed into the tree.

To attach the eye bolt to your tree, you will need to drill a hole(s), slightly smaller than your eye bolt, through the tree branch from top to bottom. Screw the bolt into the hole(s) with the eye on bottom. Screw nuts onto the threaded end of the eye bolt . Use lockwashers between the nuts and the tree to help keep the nuts from coming off.

Once you have your eye bolts in place, attach a carabiner to the eye bolt and then attach the rope to the carabiner.

Tie a rope around the tree

Place the rope over the tree and tie a running bowline knot. Put a piece of rubber tubing to keep the tree from being damaged by the rope.

Before using the swing, be sure that all of your knots are tied properly. Put a test load on the swing that is comparable to a rider to see how it performs. Make adjustments as necessary.

Tree without a branch

If you tree doesn't have a branch to support hanging your swing, you can still hang it if your tree is strong enough. There are a few options for hanging your swing on a tree without a branch. You can get an artificial branch, hang the swing between two trees, or hang it between the tree and another structure.

On going maintenance of your tree swing

Once you've put your swing in your tree, you will be able to enjoy it for many years to come. To ensure that it last a long time you will need to perform some basic maintenance.

  • Check the rope for splitting, rotting, and other damage
  • Test the tree branch for cracks, rot, and hollowing
  • Inspect any knots for weakening
  • Check the seat (wood, tire, etc..) for any damage
  • Continue to keep the ground cut, free of debris, and loaded with ample ground cover material.