View Full Version : Has anybody done a job like this?

06-08-2003, 09:15 PM
I have a very good client that wants their trampoline buried in a pit, so that the jump surface is level with the surrounding lawn. The problems I see is drainage, a solid base for the frame, and want to use to keep the surrounding dirt from falling into the pit without creating a hazard. Any suggestions would be appreciated.
The soil in the area has a high clay content, so the drainage system I picture is something like a French drain. My idea for the dirt from the pit would be to use it to raise the surrounding area, so that any rain will run away from the pit. So, the only water to deal with would be direct rainfall, which is about 50" a year (record for one day is about 8").
What I'm really concerned with is the safety issues. The family has three very active girls, with one a gymnast, and another a diver, this will get used alot. Thus, the need for a foundation and side walls built to last, while not creating any extra hazards.

06-08-2003, 09:40 PM
i've never done something like this exactly, but this is what i'd do

I'd dig a pit with a small excavator or loader/backhoe. Take care not to disturb any more soil than absolutely necessary. Dig the shape and depth out for the trampoline plus 1' for 6 inches of 4" rock with 6 inches of 3/4" trap rock ontop of that. Use a french drain like you said.

Next i would disassemble the trampoline, remove the bouncy part leaving only the frame. Put it down in the hole and build a wall with the large retaining wall blocks and make sure the top layer of block is going to be level and as close as possible to the frame of the trampoline.

The frame will be locked into the wall, but i think that'd be a fair price to pay to have the wall as close to the frame as possible. It'd also minimalize the amount of leaves/**** that gets trapped down their.

06-08-2003, 10:23 PM
And the first person who hit their head on the edge of the wall will.............. Sue you for every thing you will ever have. Run don't walk from this one.

06-08-2003, 10:29 PM
ah, they're kids, they're made of rubber, they just bounce! :D

06-08-2003, 10:56 PM
That's why I'm asking ???? to keep this project from ending up in court after an accident because of a retaining wall. Is there anything to use for a retaining wall that is no bigger than the frame pipe?
I was planning on using a skid-steer w/ backhoe attachment, mainly for the need to grade area, and hauling the gravel from the street to the pit.

06-08-2003, 11:09 PM
Originally posted by paul
And the first person who hit their head on the edge of the wall will.............. Sue you for every thing you will ever have. Run don't walk from this one.
This thing sounds like a nightmare
But on a second thought. You could run the plan by the local building inspector's office. If they issue a permit and sign off on the same then why not.

Turf Medic
06-09-2003, 01:17 AM
Originally posted by Jimmy348
This thing sounds like a nightmare
But on a second thought. You could run the plan by the local building inspector's office. If they issue a permit and sign off on the same then why not.

Having the building inspector sign off on the project won't keep you out of court if someone gets hurt. Isn't enough money out there to try this one, otherwise the trampoline companies would have come up with some type of kit to sell.

06-09-2003, 10:36 AM
i don't know what i am doing either, but this is what i think

i would dig out the ground where the trampoline is supposed to be located. then i would make a bulkhead around the entire perimeter about 2-3" away from the edge of the trampoline. (make the diameter about 5-6" larger the the trampoline).

when i say a bulkhead, i suggest taking a 4-6" X 8' post and sinking it 4' under the ground so that on only 4' or whatever the height of the trampoline is is above ground. then i would taper the top of the post away from the edge of the ground, into the hole, so that nothing gets in the way of the springs when they compress.

Then take lag bolts and secure thick pieces of plywood to the post, and backfill.

I don't know if this would help any, but it is what i would do.

John Gamba
06-09-2003, 10:39 AM

kickin sum grass
06-09-2003, 05:15 PM
you could build a retaining wall and use the wall as the frame to support the trampoline. attach the frame that the springs attach to, to the retaining wall some how. This way the hole wouldn't need to be any deeper than how far the trapoline deflects down. This would also slightly help with the drainage issue (which will be a big one unless you are on a hill). Then I would change my name, phone, and address just in case.

06-09-2003, 06:26 PM
I'm with the "Run don't walk..." group.

06-09-2003, 09:36 PM
take this in consideration:

Lots of homeowners insurance policy companies, upon finding out that the homeowner has a trampoline, will DROP the homeowners policy flat out.

So, if insurance companies, (who are in the business of selling insurance), DROP customers immediatly upon word that so-and-so has a trampoline, why on earth would anyone even think of doing a pit or anything, especially if you're asking for help on "how to" from a bunch of people you don't know from Jack on lawnsite..

No disrespect to anyone here, but I could write a post "Dig 6 inches, do this, do that, use rock and build a wall 8 inches thick.." and meanwhile I don't have a freaking idea how to do what's being asked.

My gut is telling me that if you don't know how to do this right from the get go, you're over your head, tell the customer that, and walk.

It's alot different than doing a deck, which can be re-built if it's screwed up, or landscaping where really worse thing that happens is the plant/shrub dies.......

I have 2 customers that have trampolines. I don't mow under or withint 3 inches around them. I don't move them and don't even touch them. Customers know that I don't since I explained to them that if I do move it, and something come lose and their child goes playing on it and pulls a Christopher Reeve move, I'll be the one sued for "messing with the trampoline" and no thanks. So I don't move them, and the grass can grow 15 inches tall under neath them until it eventually gets so tall it just dies. <G>


06-09-2003, 10:08 PM
what if you dug the pit and made it larger then tramp, build the wall out of used tires filled 1/2 way to 3/4 way out or all the way. Fasten tramp to tires. Its a good idea just gotta figure it out.
Or dig pit twice the size of tramp install in the ground with legs and grad pit for lowest point under center, no wall just 45 degree grade.

06-11-2003, 08:25 AM
It's ok to say no thanks .... You have to walk away from some jobs.

06-11-2003, 06:44 PM
interesting proposal...I'll try not to fill my reply with puns!

I like the idea of attaching to a retaining wall of sorts but an in question of durability and life expectancy (tramp user included). How' bout pouring footings around the perimeter of the tramp and attaching to them. I thing the idea of having a trampoline level to the ground is attractive...but if you decide to go through with it...make it equally expensive, without a guarantee-in writing

06-11-2003, 11:03 PM
I would run. I would tell the customer that my liability insurance would not cover me for a job of this nature. ;)

deere ZTR
06-11-2003, 11:57 PM
You are nucking futtzz to even think about this one way to much liability and complication:dizzy:

06-12-2003, 01:31 AM
I`d have nothing to do with it and my insurance agent would tell me to have nothing to do with it.

06-12-2003, 04:08 PM
If you don't run (I'd be in the run group also, though I like a good challenge) have your attorney draft a Hold Harmless agreement for the client to sign that says they can't sue you for anything that might happen as a result of you doing their request. That said, the only way I would do this is to essentially build a large playground around the pit and set it up so that the only thing that could be fallen on is the trampoline, or playground safety surface material installed properly to account for the fall heights. Once the customer sees the price for that, they will probably just want to keep it as is ;)

Groundcover Solutions
06-13-2003, 09:11 PM
This is no new idea. There is a place around me where you can go and use there trampoines for what ever you need like gymnastics. They have all of there trampolines in the ground if anything it would be safer. You have less of a fall to the ground if you fall off. I have seen one home that had there trampoline put into the side of a small hill. Just my 2 cents

06-19-2003, 03:08 PM
I would suggest that they get a netted enclosure for it. It will be a lot less expensive, easier to replace when the kids grow up instead of a gaping hole in the yard, an added safety feature, and less of a hassle for you.


06-19-2003, 10:24 PM
Does this woman know that they make trampolines with 8' sides now? I think too many kids were bouncing off the tramp and then off the ground.

I think I would refer this to someone I didn't like.

...and then run.

06-19-2003, 10:25 PM
Or that...

06-19-2003, 10:29 PM
Ok, I have another idea. Tell her to take the money she was going to pay you and buy herself a moon bounce.

No, really...

Advanced Lawncare
06-19-2003, 10:58 PM
I would run. I would tell the customer that my liability insurance would not cover me for a job of this nature.

Me too

06-23-2003, 09:41 PM
first thing i would do is call yur insurance agent and see if they would even cover you for a project like this.....if they say yes...then get it in writing from the insuarnce company and the customer taht you are not liable for hurt kids...finally in yur construction of this whole thing make sure you include some sort of "protective certified play ground mulch around the perimeter of the tramopline......this way when you are sued you can say well at least you tried to stop them from breaking there necks... in fact id prolly build a burm around it with the play ground muclch to serve as some sort of coushin.

i have no idea on this one

Perfect Property Services Inc.

The Green Way
06-24-2003, 06:47 PM
<A HREF="http://www.iltla.com/2002_VESTED/july_2002_torts.htm">Court Rejects Suit for Trampoline Injury</a>

In a 5-2 decision, the Illinois Supreme Court dismissed a lawsuit against a homeowner and a trampoline manufacturer saying that a 15-year-old girl should know that a trampoline stunt called "rocket jumping" is dangerous. The Court determined the girl, who injured her knee while jumping on the trampoline with friends, could not proceed with her suit because the trampoline was an open and obvious hazard. (Chicago Daily Law Bulletin – June 6, 2002)

06-27-2003, 12:35 AM
I don't see the problem if you use sound building practices. Contractors build decks, pools etc. People fall off/in or worse and the contractor isn't sued. Now if you "created" a hazard or used faulty construction methods that "caused" someone to get hurt that would be different. I would still get a hold harmless clause. The homeowner pays the $100 to the lawyer to write it up.

What about digging down and building a low deck around the tramp? Use standard construction practices, railings, etc. You could also suggest the homeowner place foam matts on the wood deck. Much better than falling off an above ground tramp.


06-27-2003, 01:18 AM
Instead of digging hole and lowering trampoline how about building walls five or six feet out from the trampoline. and filling with sand. Much softer to land on and can easily be removed later.

The inside edge of the wall could be slightly lower and under the edge of the trampoline.

06-27-2003, 01:35 AM
Heres what I mean. I don't know if they have enough room for this it would be big.

06-27-2003, 09:42 AM
I think a deck around it would be best. A bungie jump tower could be a possible add-on feature, directly above the trampoline.
Crawdad:blob3: :blob1: :blob4:

Green in Idaho
06-30-2003, 09:03 PM
Leadarrows, that would be a LOT of sand on the tramp. But I would like the pit with sand underneath the tramp.

Perhaps the desire to have it in the ground is part safety (for kids jumping beyond the tramp, but more for the appearance of it.

Cost would buy many months of membership at gym class.

Also after the kids move out it would make a heck of a pond! I would approach it with a future pond in mind.

The retaining wall can be under the outside rail. The rail and the padding would prevent kid contact with the retaining wall. Then top off the wall with 3-5 inches of soil/turf. Or line the perimeter with some groundcover so one doesn't have to mow right up to the tramp, softens any accidental contact off the tramp, and used as erosion control. OR have parents get another set of padding to go over existing and extend into the turf. A little dirt is going to settle and after a season the final result will be there.

It is possible. CYA and try the challenge. You might have a more jobs to do just like it.

Kate Butler
07-19-2003, 11:14 PM
Have you considered lining the hole with culvert to keep the interior sides stable, 2" stone in the bottom to facilitate drainage of natural rainfall, and standard gym padding around the edges? Slit flexible plastic pipe should go on the raw edge of the culvert (much like foam pipe insulation). That plus a removable safety netting (cage) should satify the aesthetics if the project.

07-20-2003, 05:57 PM
Great project..................

After reading all the post the one idea that makes sense is the concrete wall blocks for the perimeter the frame of the trampoline is set on padding on the block it just below the surface. Outer edge of using plastic edging with the round top.

If they have the trampoline now. I would venture to guess they already have pads for outside the perimeter anyway.

I would do this project in a heart beat.

And as mentioned. later on it is a water feature

07-20-2003, 09:27 PM
I'll bet not one person here has insurance to cover this type of project.

07-21-2003, 02:14 AM
I have been to one house that had a trampoline in the ground. They had a rectangular hole dug about 4 ft deep and had the bottom concreted with a drain and the sides blocked up. I think the trampoline was made to fit the hole cause the springs were attached to the sides of the blocks at the top and padded foam was added to the top of the blocks and springs with a layer of pea gravel on the outside of the blocks. It actually looked more safe than a standard trampoline off the ground.