Building a Skinner Air Crib

I recently wrote about my experiences with B.F. Skinner’s Air Crib (or if you prefer, Baby Boxes). In this post, I’ll share what I remember about how the cribs my daughter and siblings and I used were made.

What is a Skinner Box? In this context, it’s a temperature-controlled, enclosed baby crib that requires no sheets, blankets, crib bumpers or other bedding. The essential ideas are to allow babies maximum freedom to move around and sleep without being constricted by clothing; to reduce laundry quantities to the minimum; and to allow the room the baby sleeps in to be used as more than just a nursery. Best of all, an air crib puts the baby at adult eye level — great for interaction, and also easy on backs.

These aren’t plans, per se . . . one of the advantages of the air crib is its flexibility, and adapting it to your circumstances is pretty much the point. Implementation is up to you — make it quick and basic, get a pro to draft a blueprint, or hire the whole job out and have a craftsperson make it out of old-growth-forest walnut. (Now that’s an heirloom!)

Here’s the short version — the ‘what-needs-to-be-done’ list:

• Build a big box with an open front
• At about waist level, build a ledge to support the mattress
• Below the mattress supports, cut holes for two ventilation screens, making sure they face each other for best air flow
• Add two light bulb sockets at the right and left sides, below the mattress ledge (these provide heat)
• Link the sockets to an external switch on the crib
• Build a protective shelf (screening or perforated) above the light bulbs (lift-out, if you’re not going to have access through the front) below the light bulbs
• Build another shelf (also of screening or perforated material) (also, lift-out, if you’ll need access from the top)
• Install a thermostat outside the box where adults can reach it
• Place shallow evaporation pans below this second shelf (these control humidity)
• Install a small fan in the ceiling
• Make a mattress frame and lace a mesh mattress to the frame
• Attach door(s)
• Add legs or a cabinet beneath

Details:

The two cribs my siblings and I used were identical and made from Masonite (lightweight but strong) and were set on wooden legs — probably 2x2s. You can just barely make out the legs in this black and white picture of our first Baby Box.

The doors were heavy glass, and opened just like any cabinet; they had latches all over the place to ensure that nobody took a tumble. The dual doors on our childhood boxes opened across the entire width of the crib; my daughter’s had a single door, not nearly as wide, but perfectly suited to the job, just the same.

My daughter’s box was built-in, and took up approximately the space of a small closet. Hers had the single door in the front, but also had a non-opening window on one end, making it very light and airy. The interior walls were tongue-and-groove-pine. The dimensions were about 46 inches wide by 24 inches deep; my daughter’s crib was about 4 1/2 feet high. This size gave her plenty of room, since she was quite small. The ones my siblings and I used were a fair bit larger; a standard full-size crib mattress in the USA is 28 inches by 52 inches.

All of these boxes were technically quite simple — you could get elaborate if you wanted to, but it’s definitely not necessary. The light bulbs are the heat source; I think we used 40 watt bulbs in my daughter’s box.

Our thermostats (and later, my daughter’s) were sold for use in chick brooders; if you don’t happen to live either in a time warp or a rural area, you can probably find something just as effective at any hardware store. Our childhood boxes plugged into ordinary outlets; my daughter’s electricals were hard-wired, just the way you’d install a bathroom fan or light fixture.

Our mattresses were composed of a rectangular frame which was supported by the ledge. A canvas pocket (like a large pillowcase) slipped over the frame, and was removed for washing.

A modern mesh fabric made my daughter’s mattress much easier to use than the ones from my childhood — it was laced across the underside of a frame made of conduit pipe. PVC pipe could work, too, but would probably require wooden dowels inside for reinforcement.

To make the mattress, I finished the edges of the mesh with a binding tape and grommets along all sides. On the ‘wrong’ side, the fabric wrapped around about 25% of the area of the mattress on the each side. (You can just barely make out the shadows of the edges in the image above left.) Having two would be most convenient.

The shelves above and below the light bulbs were a metal screen (ours) or perforated metal (my daughter’s). The shallow evaporation pans for all three of these boxes were ordinary baking pans. (Four, brownie-sized — 9 inches by 9 — in my daughter’s case.)

Screens on either end of the lower part of our childhood cribs allowed for air flow, and there was a fan above to circulate it. My daughter’s was designed so that air flowed up from below; a fan was installed in the ceiling.

The air cribs from my childhood were light enough that they were moved around the room occasionally. I think one of Deborah Skinner’s boxes had wheels or casters beneath it — a better plan, especially if you want to move yours from one room to another. Our boxes had simple curtain rods at the top, and lightweight curtains to pull across the front so that anyone moving around the room didn’t catch the baby’s eye when said baby was better off sleeping. Deborah’s had a pull-down shade.

Maintenance was pretty straightforward. Rinse, wash or scrub the mattress as needed and check the water in the evaporation pans. The water is what controls the humidity; you’ll want to keep an eye on it.

Other tips and notes:

Air-conditioning was not a consideration where we lived (southern Michigan before global warming; rural northern Michigan later), though I do think I recall my parents putting ice cubes in the evaporation pans during one hot summer. In more extreme climates, it might be necessary to make some more formal provision for cooling the air crib.

If you use a wheelchair, you’d probably want to shift things around a bit so that you’re slipping the chair right under the center of the mattress. In that case, you’d end up with the internal bits on either side of the wheelchair access, rather than placed all the way across the box beneath the mattress.

I added a toy bar at one end of my daughter’s crib, with a rather nice little music box which she loved to play (pictures above) — and this appliqued ‘sky’ to the ceiling.

Previously: A Better Baby Crib for Parents Who Use Wheelchairs