We want a really big sand box - how much play sand will we need?
I'll answer this in two parts - first I'll give you an idea of how much sand weighs and how much space it takes up, then second I'll describe how much play sand a big sandbox needs in terms you can easily understand.
First let's start with a little background info and I'll provide some numbers so you don't have to do the calculations (but if you want, use our Sand Calculator for your size sand box).
I'll use some common things that you can relate to like a five gallon bucket, a large garbage can, a small and large pick-up truck and a dump truck load. And we'll use a couple of sand boxes as examples like the Little Tikes Green Turtle and the Crab sand box, a 5 ft by 5 ft wooden sand box under a play set, a bigger 10' x 10' sand box and finally, a big sandpile that is the dream of every kid.
Here is how much sand these item will hold:
- 5 gallon bucket = 70 pounds of dry clean play sand (80 to 90 lbs if wet sand)
- Large Plastic Garbage can (50 or 55 gallon size) = 700 to 770 lbs if play sand is dry
- Small Pick up trucks like the Honda Ridgeline, Toyota Tacoma or Nissan Frontier are called half-tons but in reality it is also a function of how strong your tires are. If you have the factory tires that came with the truck then don't get more than a half-ton load (=1,000 lbs). DO NOT fill up the whole empty bed of your truck because if you do, you'll break your springs or blow your tires, guaranteed.
- Larger trucks like the Ford F-150, Toyota Tundra, Ram 1500 or Chevy Silverado are all considered to have a 3/4 ton payload capacity with factory tires. Everything I said above for small pick up trucks are also true here.
- Dump trucks - these are the kind you see in town. We are NOT talking about the massive tandems you see on the interstate highway - they are way bigger. Most of the local dump trucks will hold 10 cubic yards of sand, topsoil or mulch. Think of a cubic yard as a pile of material that is 3 feet by 3 feet by 3 feet. Something like clean play sand is pretty 'dense' compared to wood chips and typically weighs about 2,800 lbs dry.
Do the math and therefore a 10 yard dump truck of sand box sand would weigh about 28,000 lbs. if dry.
So now let's talk about how much sand you need if you want a 'big' sand box. And of course everyones idea of big varies depending on how much space and dollars you have.
I consider any sand box made out of plastic to be 'small'. There are lots of them on the market - the Little Tikes Green Turtle and the Crab sand box are just two of many. Most hold anywhere from 100 to 400 lbs. of clean play sand if filled half-way.
And here is an important fact to decide on: how deep do you want the sand to be? Please don't automatically say "a foot deep". That is a lot of sand as you will see.
The correct question is "how deep are the sides on my sand box" and my recommended answer is "then I want the playsand to fill it half-way". This is based on 25 years selling play sand and observing kids in sand boxes at numerous schools, daycares and preschools that use our Jurassic Play Sands.
What it all boils down to is the kids need room to move the play sand about, pile it up, etc. Every sand box that I have seen filled to the top always has a ton of sand around it that has been pushed out because the kids need room to do their thing. Then that spilled sand kills the grass and you have more work to do. Fill it half way please!
Now that we have that out of the way, let's talk easy-to-visualize numbers because sand is heavy (dense is a better word but I promised to keep this non-technical). Think how hard it would be to carry a 5 gallon bucket of damp, clean play sand weighing 75 or 85 lbs. in each hand around to the back yard. Oh, a wheel barrow - well now you're 'pushing' 200 or 300 lbs - that's still way hard.
Here's why this is important. Let's go back to 5' x 5' sand boxes under the wooden play set. Usually the sides of the sand box are 8 inches high so if we fill it half-way that's 833 lbs. (Here's the math 5' x 5' x 4"/12" x 100 lbs per cubic ft = 833 lbs of DRY sand). If the sandbox sand is damp that's easily 1,000 lbs.
That doesn't sound to bad if you are young and in shape but perhaps you decided you wanted a bigger sand box - say a 10' x 10' that has 8" sides that you fill half-way. The SHOCK of the math to most people is they think that's twice as big as a 5' x 5' box.
WRONG! It's actually 4x bigger so that means you'll be moving between 3,330 lbs to over 4,000 lbs of play sand!
Okay so you say The Jurassic Sandman is out to lunch on his recommendation to fill sand box sand half-way and you want at least a foot of sand like you "had as a kid".
This can be a good idea - it's what The Sandman had as a kid and I loved it. But my Dad was the one who did it because my Mom said that is what she wanted for her kids (go Mom!).
So Dad was probably thinking, "I can save myself a lot of work (and expense) NOT building a sand box" (very true), "we'll just dump it on the ground and make a sand pile instead". GREAT idea except the landscaping and fence was in, and the trees were grown and in the way but the 20 foot by 20 foot area in the backyard was all ready for sand...
Turns out that much play sand weighed 40,000 lbs dry and was close to two full dump truck loads! So they just dropped in our driveway since most cities have ordinances against dropping it on the street. It took a small army of wheel barrows and resulted in exhausted family members to move that much sand in a reasonable amount of time.
I could go on about the logistics but the point is clear. Be prepared for what you are getting into.
And one final thought that no one thinks about. Eventually your kids are going into high school, your significant other is sick of looking at that pile of sand (now spread out over twice the area) and longs for [fill in the blank; grass, flowers, a patio, etc].
Eventually the time to remove the play sand will come and even though there's only half as much there (thank you wind and to Junior for spreading it all around the yard), you are 15 years older and have about 1/10th the free time you use to have.
Don't get me wrong about this; if you have the space and budget (and energy) definitely go BIG. Your children will thank you when they grow up and when they think back to all the good times they had in that sand box with family and friends, and probably even Mom & Dad, they will have you to thank.
And hopefully your children will follow your example and start planning their own 'big' sand box for their kids (and you know, your grandkids will love it and it is the right thing to do)...
Thanks for joining me on this part-Sandipedia, part-personal memories of the good-old days - Best regards - The Jurassic Sandman Geologist Jerry on Nov. 16, 2016 from sunny Southern Utah as I sit (and play) on a big pile of sand.