All Trampoline Country’s trampolines can be lowered into the ground. The following are important aspects to consider with respect to in-ground trampolines.

Shape
The shape of the trampoline is of utmost importance. While a hole can be dug for any shaped trampoline, the simplest hole to excavate would be for the rectangular trampoline.

Retaining Wall
Once your hole has been dug, it is important that the walls do not collapse, thus a retaining wall would need to be constructed. There are a number of options available for this. If a more permanent retaining wall is required, concrete may be considered, either poured or in the form of concrete blocks. If a less permanent wall is required than pressure treated wood could be an option.

Soil type, water table and drainage
It is important to ensure that there is sufficient drainage under the trampoline, thus soil type is critical. If the water table is not too high and the soil is sandy there may be sufficient drainage; otherwise a drainage system may be required.

Foundation
Trampolines need to be level and have a solid base, thus the legs should be placed on concrete pads or a wooden base. If they are placed on a wooden base they should be clamped firmly to the wood. If they are placed on concrete or patio stones than a ¼” layer of rubber should be placed under the legs to prevent them from moving and being damaged on the concrete.

Elevation
We recommend that the trampoline be elevated above the ground level by approx 3” - 5”. If the trampoline is level with the ground surface, the performance may be hampered since there is no “escape route” for the air being pressed down. For example, air is being pressed down as the bouncer lands on the surface of the trampoline. If there is no gap for air to escape it will return to the underside of the trampoline mat, thus reducing the bounce.

The following are some examples of in-ground trampolines.

The 11' X 17' above is only partially sunken into the ground. Notice the 2” X 6” planks used for the retaining wall. It is a good idea to use 4” x 4” upright posts in the corners and along the length and width of the retaining wall to support the wall.

Perhaps two additional supports along the length and one along the width would be sufficient; the number used would depend on the soil that is held back. This particular trampoline is resting on patio stones and crushed stone is used for drainage.

The 11' X 17' trampoline above is completely sunken into the ground. Notice the block retaining wall, sandy soil for drainage, and the patio stones on which the trampoline is resting.

The top of this retaining wall is covered with custom made pads.

This 10' X 14' trampoline below is also completely sunken into the ground; however, the retaining wall is made of wood rather than cement blocks.

Notice that crushed stone is used for drainage rather than sand and the legs are placed on a raised concrete pad.

It is recommended that a ¼” layer of rubber be placed under the legs to prevent them from moving and being damaging by the concrete. The wood retaining wall is also fitted with a custom pad.