There’s nothing quite like watching your children discover the magic of a sandbox in your backyard. Not every playset has a space built-in for a sandbox, though. Thankfully, making a sandbox under your children’s playset is one of the simplest and cheapest DIY projects you could embark on.
Built-in backyard sandboxes are not only fun to make, but they only take a day or two to finish. With the right tools and materials, you can be playing with your kids in their new sandbox in no time!
How Big Should the Sandbox Be?
Before you start building, measure the space under your child’s playset so that you know how much space you have to work with. Sandboxes work best under playsets that are set higher up, so you don’t have to worry about your children bumping their heads when they stand up or move around.
You should also decide if you want to leave space between the sides of the sandbox and the playset or not. Your kids are more likely to trip over the sandbox’s sides when they get in and out if the walls of your sandbox don’t touch the playset.
If you leave some space around the border, your kids could sit on the edge. This prevents them from kneeling in the sand or being pushed up against the walls underneath the playset. You should also consider how many children will be playing in this sandbox before you build it and how long you want it to be around.
A few toddlers may be comfortable in a smaller space, but as your children grow, their sandbox may become cramped. Building your sandbox into the ground rather than as a freestanding frame lets you make a bigger sandbox area for your children to play in.
Know that the bigger the sandbox you build, the more it is going to cost, so be sure to come up with a budget before you start building.
Tools and Materials You Need
Here are the tools you need for the job. We included links to some of our favorite options if you don’t have any of these tools yet.
Some people opt for plastic sandboxes over wooden ones. They are easy and fairly inexpensive to buy from the store, usually come in various fun shapes and colors, and you can move them around as you please.
However, plastic sandboxes are not as durable and sturdy as wooden sandboxes. If you are looking for something that will last through your children’s early years and are willing to do a little maintenance work, wooden sandboxes are the way to go.
As long as homemade sandboxes are made with safe materials and maintained properly, they are perfectly safe for your children to play in! Be sure to use nontoxic landscaping timber and beach sand, natural river sand, or specially marked play sand.
You should avoid sand products that are dusty or made from crushed marble, crushed limestone, or crushed crystalline silica, better known as quartz. Masonry and paving sand is also not suitable for sandboxes.
Prices for play sand may vary, with color or sustainably sourced play sand usually costing more. You can use our sandbox calculator to figure out how many bags of sand you need.
You should also avoid using inexpensive railroad ties in your building process as they could cause splinters or contain the carcinogen creosote.
Step-By-Step Process for Making a Sandbox Under Your Playset
Here’s what you need to know about each step when making a sandbox under your playset.
Digging Out the Area
When you level the area for your sandbox, be sure to remove any roots, rocks, or other intrusions that could damage the bottom of the sandbox. Lay the boards out to indicate the exact area where you’ll place your sandbox.
Next, mark the outside perimeter using spray paint before removing the boards. Now you can dig out the inside of your sandbox’s perimeter. If you’re unsure what utility lines may bein your path, be sure to call the Digline at 811 before you start digging.
You should be able to dig to a depth of three to six inches for your sandbox. Use a carpenters’ level to make sure the hole is level. The depth of your sandbox will depend on whether you are building your frame or using the frame of the bottom of the playset.
When it comes to preparing the space and digging the hole for the sandbox, it is usually safer to do it if you are building your frame. Instead of attaching the frame of the sandbox to the posts of the playset, you just build around them.
Just be sure not to dig out any earth around the posts. The last thing you want to do is mess with the sturdy foundation of the playset.
There are two ways to level the base of your sandbox. You can either fill it with sand or if you are worried about the sand leaking out from the boards and mixing in with the dirt in your yard, you can add fabric. Make sure the landscape fabric covers the bottom and sides of the hole.
It is important to remember, the easiest shape sandbox to build under a playset is a square or rectangular one. As fun as the geometric shapes are, they are usually harder to build, especially under a structure like a playset.
Building the Frame
Make sure you get the size you need! When you join boards together to make a sandbox, the individual boards will be shorter than the size of the sandbox you want. So you should make sure to measure the area and decide how long you want each side to be, and then buy lumber that is 3-½” shorter than you want.
Or you can always use your circular saw and cut the boards to size yourself after you get home. Just don’t forget the age-old rule: measure twice, cut once!
Laying the Foundation
Place your lumber around the perimeter of the hole you dug, making sure it sits flush with the dirt. Use your level again to make sure the bottom layer of lumber is even before using a drill to create holes about a ½ inch down from the lumber to the ground.
Then use a mallet and rebar spikes to attach the lumber to the ground. Now you can add the second layer of lumber to your sandbox and screw the corners together. Once everything is level and secure, you can add your sand.
Pouring the Sand
To figure out how much sand you need for your sandbox, just multiply the length x width x depth (not to the top, just where you want the sand to fall), and divide that number by 27. This number equals the number of cubic feet of sand you’ll need to fill the sandbox up to the depth you want. Or, like I mentioned above, just use our sandbox calculator.
To prevent contamination from insects or other animals, you should keep your children’s sandbox covered when it’s not in use. Make sure to let the sand dry out completely before covering it as wet sand can harbor bacteria.
Sandboxes should also be raked regularly to remove clumps, lawn debris, and other foreign materials. You should also avoid letting your pets play in the sandbox as they may try to use it as a restroom.
Your sandbox cover should be tear-resistant so you don’t have to worry about replacing it every year and UV-resistant so you don’t have to worry about it fading over time. Wooden sandbox covers look great, as long as you take care of them and cover them in waterproof coating. We really like this option from Maius.
However, the best sandbox covers are made of mesh vinyl. Mesh vinyl covers keep sand ventilated and let it dry quickly while preventing pooling water that leads to mildew or mosquito breeding ground.
At the end of the day, it’s up to you how you choose to cover your kid’s sandbox. As long as your children are safe from bugs and possible contaminants, that’s all that matters. There are several options of sandbox covers you can choose from.
You know the fencing you usually see around a garden? This kind of cover won’t protect your children’s sandbox from rain or bugs, but it will keep out small animals like cats. Unlike wood, this vinyl material resists warping and is weather resistant.
Plus it’s cheap and doesn’t require any installation. You just lay it on top of the sandbox and you are good to go!
Polyester or Nylon Fabric and Stakes
If you want more of a whimsical look, you can stake down some water-resistant polyester or nylon fabric over the sandbox. Try using a colorful parachute and staking down the handles.
Build Your Own Cover
Depending on what materials you use, you can spend the day building your inexpensive sandbox cover. You can customize your design to fold out into seats for your kids or you can even make some hinged doors with handles so you can open the sandbox like a cellar.
Just make sure you drill some holes in the wood to keep the sand ventilated.
Cover With Drawstring
This kind of cover is easy to fold up and store away. It’s waterproof, ready-made, and comes in a variety of sizes. The special drawstring keeps the cover secured around the perimeter of the sandbox, so you won’t have to worry about any water, animals, or lawn debris getting in.
This kind of cover is heavy enough that it keeps your sandbox covered without requiring snaps or ties to keep it in place. It’s made from vinyl or mesh and is available in a variety of sizes.
Although this cover tends to be on the pricier side, it is worth the investment if you’re looking for sturdy coverage.
Safety and Maintenance
Besides using a cover for your children’s sandbox, you can also follow these tips to make sure they are staying safe while having fun!
Make sure you keep out dirty diapers, hands, and feet from your children’s sandbox. Always have your kids wash their hands before and after they play in the sandbox. If they are going to be going barefoot in the sandbox, they should also wash their feet before and after. Have your kids change their clothes after they play in the sandbox.
Check the sand for debris often. If you find urine or animal feces, you will need to scoop out all the sand around the affected area. However, the safest thing to do is to scoop out and replace all of the sand in the contaminated sandbox. This is especially true if the sandbox is used by young children who may put their hands in their mouth and be exposed to the toxins.
Try sanitizing the sand every so often with a mixture of one part water and one part distilled white vinegar. You should also change the sand in your children’s sandbox at least every other year, or every year if it is used a lot by several children.
You also have to watch for splinters or rot in the wood so you can repair or replace sections as needed to avoid your children getting injured.
For more tips on safety and maintenance, head over to our full sandbox maintenance guide.
I know that’s a lot of information to digest, so if you have any questions, don’t hesitate to reach out to us. Best of luck building your new DIY sandbox!