ᐅ Installing a trampoline flush with the ground

Hello everyone,

since we will soon need to hire the excavation contractor, we would like to also have a pit dug in the garden for a flush-mounted trampoline for the kids. Ideally, this circular excavation could later be used for a paddling pool. That means you would sink a paddling pool with a metal frame into it.

My question: Has anyone done this before? What should you watch out for? How should the hole be reinforced? With concrete formwork? Just fill it with gravel? Do you need a drain pipe to the sewer? How much did this cost for you?

Thanks in advance for your experiences and tips!

Good idea
We have a recessed unit like that on our playground.
Unfortunately, I can’t provide any further help.


Regards

Traumfaenger schrieb:
Hello everyone,

Since we will soon need to hire the civil engineer, we would also like to have an excavation in the garden for a flush-mounted trampoline for the children. Ideally, this circular excavation could later be used for a paddling pool. That means placing a paddling pool with a metal frame into the ground.

My question: Has anyone done this before? What should we pay attention to? How should the hole be reinforced? With concrete formwork? Just fill it with gravel? Do you need a drain pipe to the sewer? What did it cost you?

Thanks in advance for your experiences and tips!

The problem is that the paddling pool has different dimensions than the trampoline. In my opinion, neither the trampoline nor the paddling pool require special preparations. It’s better to keep it "old school."

Traumfaenger schrieb:
What should you watch out for?

The air displaced during jumping needs to be able to escape. There are special ground-level trampolines (a brand name would be "In-Ground Trampoline"), whose manufacturers claim that their special frame takes care of this function.

In my opinion, there are no high demands on the pit itself: it should be as deep as necessary in the middle, about 75 to 100 cm (30 to 40 inches), depending on the trampoline, and shallower toward the edges (bowl-shaped). Therefore, I believe no special slope is required. If the ground is reasonably permeable, any water will be able to drain away. The trampoline itself should be secured/anchored as it would be without a pit.

Also, you should ensure that no one can slip into the pit at the edge of the trampoline (or get their leg caught between the slope and the frame).

What exactly is the excavator supposed to do? Digging a basement? Pouring a foundation slab? Is the trampoline already onsite? Are you already living there? I would probably avoid having the excavator create the trampoline pit and do it myself later. Keep in mind that damage can occur around the area as well (excavator movements, soil compaction, etc.). From my own experience, I would prefer to keep the excavator out of my garden...

There are two options for installing a trampoline flush with the ground.
1. To install a regular trampoline with its legs recessed flush into the ground.
2. To set up an inground trampoline.
Both have their pros and cons.

Option 1 looks good, but:
It requires more time and higher costs to dig the pit.
The frame can either be assembled beside the pit and then lowered in, or assembled inside the pit if there is enough space.
The springs must be stretched while kneeling.
If anything falls inside (toys, keys), it is difficult to retrieve.
Animals that fall in cannot get out.
Small children might run onto the trampoline while others are still jumping.
Jumping lands directly on the ground (higher risk of injury, e.g., ankle).

Option 2, inground trampoline, is less dramatic:
It stands about 20-30cm (8-12 inches) above ground level.
Only a shallow pit is needed, which is easier to make.
The dimensions of the pit depend on the trampoline manufacturer:
Diameter of the trampoline minus 60cm (24 inches).
The deepest point should be at least 1m (3 feet) below the jumping mat.

Installation:
Excavate the pit to the required depth; depending on the soil condition, provide drainage or a soakaway pipe. For flush installation, add gravel, possibly with a geotextile membrane.
For the flush installation option, shell limestone wall blocks are often used as a border. Therefore, the diameter of the pit must be larger accordingly.

To me, it sounds like the groundwork contractor is coming to excavate for the house.
A clear recommendation: wait with that until it’s time to work on the exterior landscaping.
The groundwork contractor will have to come back anyway and can take care of it then. Doing it now won’t be very helpful.