How to Install an Inground Trampoline: The Complete DIY Guide
Inground trampolines are far safer than their above-ground counterparts. Instead of being raised several feet above the ground, they’re more accessible and create fewer risks of serious falls. Kids and adults alike love jumping on full-sized in ground trampolines, so it’s well worth the investment of a few hundred dollars and a little bit of time to make one.
Until recently, homeowners who wanted to surprise their kids with an amazing backyard gift had few options other than buying expensive kits or paying landscapers thousands of dollars for professional installations. Now, there’s a better solution. All aspiring inground trampoline owners need to do is follow the steps below to find out exactly what it takes to get the project done for less.
Step One: Gather Tools and Materials
One of the great things about DIY inground trampoline installations is that they can be completed using just a few simple tools and easy-to-acquire materials. In terms of tools, property owners will need:
A shovel
A level
Some tin snips
A hammer
A drill
A tamping device or another means of compacting dirt
With the exception of the tamping equipment, most handy homeowners already have all of these tools on hand in their workshops or garages. They’ll also need to purchase some supplies. Before getting started, head to the store to pick up:
· Eight pieces of 2″x4″x12′ pressure-treated lumber
Four sheets of 4’x12′ roofing metal
A box of 1½” self-tapping screws
16 u-groove cinder blocks
A trampoline
Gather all the tools and materials in advance before taking the next step to make sure everything will go smoothly.
Step Two: Dig the Hole
As anyone who has ever planted a tree or installed a fence by hand knows, digging is hard work. Most homeowners contact Idaho Falls excavation companies instead of digging their holes by hand. It’s relatively inexpensive to have an excavation company perform this work, and it can save a lot of time and sweat equity.
The hole will need to be a foot larger than the trampoline. For a point of reference, standard full-sized trampolines are 14′ in diameter, which means the hole will need to be 15′ wide. It should be deep enough that only the top of the trampoline sticks out. If the hole dug with an excavator isn’t quite wide or deep enough, it shouldn’t take long to extend it slightly using shovels.
Step Three: Level the Trampoline
The next step is to place the u-grooved cinder blocks in the hole and level them. The trampoline legs will rest in the grooves, so place the blocks appropriately. It should take four blocks to support each leg of a full-sized trampoline.
The easiest way to level the trampoline is to place the level on a 2×4 that’s long enough to extend across its entire width. Dig the blocks into the dirt as needed to provide stability and ensure the whole system is level. Just keep in mind that there should be at least two to four inches of space between the trampoline’s surface and the surrounding ground to ensure proper airflow.
Step Four: Build the Support Structure
Once the blocks are placed correctly, remove the trampoline from the hole. DIY builders will want to construct the support structure above the ground.
First, pull out the 2x4s and cut them at a 22.5 degree angle. Attach each of them to the trampoline’s legs using self-tapping screws and extend the support frame all the way around it. Repeat the process to install another layer of 2x4s about a foot below or above the first one.
Step Five: Add the Sheet Metal
The 2x4s installed in the previous step will provide an excellent frame for securing the roofing sheet metal to the sides. Each sheet should overlap the previous one by around two feet. Homeowners can cut off the excess metal using tin snips if they want to, or they can leave the overlap. As long as the sheet metal is bent to fit snugly alongside the 2×4 frame, either solution will work fine.
When installing the sheet metal, make sure that each sheet extends around 4″ past the top 2×4. Once the metal is installed, it can be folded over the top of the frame and screwed securely into place to prevent sharp edges from sticking out. To accommodate the legs, just cut a small slit in the metal using the tin snips, fold down the sides, and screw them into place.
Step Six: Place the Trampoline
The trampoline and its frame should now be ready to be placed in their final position. Try to gather some strong family members or friendly neighbors for this step, because the trampoline will be heavy. When placing the trampoline in the ground, make sure each leg makes its way back into the grooves of the cinder blocks, then double-check to make sure it’s still level.
Step Seven: Backfill the Dirt
The final step is to backfill dirt on the inside and outside of the trampoline frame. Make the outside dirt level with the ground, and slope the fill on the inside towards the center. The dirt should extend at least a third of the way up the frame to make sure the trampoline stays in place while it’s in use.
It’s a good idea to tamp the dirt as it’s being filled in. Homeowners can do so by buying or renting a tamper or they can get a little more creative and make their own dirt tampers. Ignoring this step can affect the trampoline’s stability, creating safety concerns and potentially undoing some of the hard work required to install the inground trampoline.
Get to Jumping
Once a DIY inground trampoline is fully assembled and installed, it will work just as well as the ones some people buy as kits and pay landscapers to install. The difference is that taking a DIY approach will almost certainly cost much, much less. It’s pretty inexpensive to hire an excavation company, and most of the tools required to put everything together are commonly found in any household garage, so the only real expenses are the materials used to construct the frame and the trampoline itself.