Just when we thought the sandbox saga was finished, there was one more twist. We’ve already shown how we built the base of the box here and how we made a lid with a locking system that secures to the fence here, but the project didn’t quite end there. That’s one of the funny things about DIY: some jobs balloon into multiple posts and others turn out to be easy. When we last left off, our daughter Clara was enjoying the freshly completed sandbox – cover and all.
The next day, while clearing out the empty play sand bags and loading a couple of extras into the car to return, Sherry spotted a warning printed on the bag that made us pause.
If the small print is hard to read, it says: This product contains small amounts of crystalline silica, a common mineral found in natural sands and stones. Excessive inhalation of respirable silica dust may cause cancer and lung disease. Avoid breathing dust. Wear approved respirator in dusty area.
That line about cancer and lung disease seemed out of place on a bag labeled “play sand” meant for children. We started digging online and found several articles examining the safety of certain manufactured sands. Clara also left her first play session covered in a fine white dust, which added to our concern. While many of us grew up playing in river and beach sands without obvious problems, some modern manufactured sands contain higher levels of crystalline silica or other minerals that can be hazardous when inhaled as dust.
To better understand the issue we looked at trustworthy medical resources and guides, including the summary shown below from WebMD that explains the health risks of respirable silica dust and why it’s a concern in some play sands.
Because we wanted to be comfortable letting Clara play for hours without worrying about inhaled dust, we decided to swap out the sand for a safer, low-dust alternative: pea gravel and small pebbles. It’s an easy solution that many families use — sometimes called a rock box — and it felt like the right choice for our yard and child. Plus, Clara had already shown a preference for playing in gravel at the hardware store planter, so this wasn’t totally new to her.
Removing the sand wasn’t glamorous. We dug out the sand and hauled it a short distance into the woods behind our property. It wasn’t the most fun half-day task, but it was straightforward and gave the box a clean slate. After sweeping and leveling the base, we started filling with small bags of pebbles.
When the pebbles arrived they were dusty from storage and handling, so we rinsed them in batches in a wheelbarrow. It felt a bit silly at first, but when the rinse water ran dirty we were glad we took the time—the washed stones looked much nicer and were less likely to leave a dusty residue on Clara’s clothes and hands.
Once the rocks were clean, we filled the box. I used roughly 20 bags to bring the surface level with the surrounding ground so Clara wouldn’t have a big step up on any side, while still giving her a few inches of depth to scoop and dig. The pea gravel was actually less expensive than the play sand we’d bought—about $2.50 per bag—so filling our 25-square-foot box cost just under $50. For us, the modest added cost was worth the peace of mind.
We also mulched around the perimeter to tidy the area and help define the play space. When Clara came back from her grandparents’ house she dove right in. We expected questions about where the sand went, but she didn’t miss it — she was excited to get digging and scooping with the rocks. The chunkier material didn’t slow her down; she can scoop with a small shovel and pick up stones easily with her hands, and she’s delighted to fill toy trucks and buckets one pebble at a time.
In practical terms the rock box has been less messy than sand. There’s occasional dirt to rinse off, but we’ve avoided the pervasive, fine dust and the pre-house-entry dust-off routine that came with the sand. We’ve also explained to Clara that the rocks belong in their box, and so far she understands that they’re played with there.
So that’s the final chapter of our sandbox trilogy: build the box, make a locking lid, and choose a safe, low-dust fill. Have you ever finished a project and then made a last-minute change like this? Some DIY tasks that seem small end up stretching into full weekends, while others that you expect to be huge turn out to be simple. DIY keeps us humble, but that’s part of the fun.
Psst—if you want to follow along from the beginning, here’s Part 1 (building the base) and Part 2 (the locking lid that secures to the fence).