DIY blackout window solutions that work
You don't need to spend $300 on custom shades. Six DIY blackout methods, ranked by darkness, install time, and cost.
Sleep · How-to
TL;DR
The gold standard for nursery blackout is foil-faced foam board taped over the inside of the window frame. It costs about $15, blocks 99 percent of light, and takes 10 minutes to install. Other methods (blackout cling film, sleep tents, cardboard, foil-blackout curtains, stick-on blackout sheets) all work, with trade-offs in aesthetics and removability.
Need help dialing in nap and bedtime schedules to go with the darker room? Use our free wake windows calculator.
Why blackout actually matters for baby sleep
Babies and toddlers produce melatonin in response to darkness. Even a little light disrupts melatonin production, which causes shorter naps and earlier morning wake-ups. The 5 a.m. wake-up problem is, half the time, a light problem.
The threshold matters. You want darkness so complete that you can't see your hand in front of your face. Most "blackout curtains" sold at big-box stores let through 5 to 10 percent of daylight. That's not enough.
Method 1: Foil-faced foam board (the best)
- Cost: $10 to $20
- Install time: 10 minutes
- Darkness: 99 percent
- Reversible: Yes
Buy foil-faced foam insulation board from a hardware store. Cut it to the exact size of your window opening. Wedge it into the frame, foil side facing in. The friction fit holds it in place. Add a strip of painter's tape around the edges to seal light leaks.
This method is the closest you can get to a hotel-room blackout without paying for one. It comes out in 30 seconds for daytime visits to the room. Stores flat behind a dresser.
Method 2: Blackout cling film
- Cost: $20 to $35
- Install time: 30 to 60 minutes for first install
- Darkness: 97 percent
- Reversible: Yes, but reusing it once peeled off is tricky
Static-cling blackout film sticks directly to glass. Mist the window, smooth the film on, trim edges. No adhesive. Comes off cleanly when you move out.
The big upside: looks more polished than foam board. The downside: light leaks around the window frame remain unless you also add curtains.
Method 3: Travel blackout sheets (great backup option)
- Cost: $15 to $30
- Install time: 2 minutes
- Darkness: 95 percent
- Reversible: Fully, every day
Travel blackout fabrics use suction cups, Velcro, or grommets to attach to windows. They were designed for hotel rooms but they work great in apartments where you can't modify windows.
Choose the suction-cup kind for renters. The Velcro versions hold longer but leave residue.
Build a schedule that uses the dark room
A truly dark nursery only helps if naps and bedtime are also timed right. Get a wake-window plan for your baby's age.
Try the calculatorMethod 4: Cardboard + black tape
- Cost: Free to $5
- Install time: 15 minutes
- Darkness: 95 percent
- Reversible: Yes
Save the box your stroller came in. Cut to window size. Wedge into the frame. Tape the edges with black duct tape or painter's tape.
This works. It's ugly. It looks like you boarded up the windows after a hurricane. But for a sleep regression week, it's the cheapest fast fix.
Method 5: Layered blackout curtains
- Cost: $50 to $150
- Install time: 1 hour
- Darkness: 90 percent (light still leaks around edges)
- Reversible: Yes
The standard recommendation, but the most overrated. Curtains alone never reach hotel-room dark because light leaks at the top, sides, and bottom. The fix: layer curtains with foam board or cling film on the actual glass, then use the curtains for aesthetics.
If you go curtain-only, pick floor-puddle length, wider-than-the-window rods, and wraparound side panels. Add a magnetic strip along the side to seal edges.
Method 6: Sleep tent or pop-up blackout canopy
- Cost: $80 to $150
- Install time: 5 minutes
- Darkness: 98 percent inside the tent
- Reversible: Yes
For travel, hotel rooms, or shared kid spaces, a pop-up blackout sleep tent that fits over a Pack 'n Play creates a dark microenvironment without touching the windows. Great for vacation. Less practical at home as a daily solution because they take up floor space.
The 2 mistakes that ruin every method
Mistake 1: Ignoring edge light
Most blackout fails happen at the edges, not the center. Light leaks under the curtain, between the curtain and the wall, at the top of the rod, and around the frame. Wrap, seal, or tape every edge.
Mistake 2: Forgetting the door
Hallway light under the nursery door is the number-one underrated cause of early-morning wakes. Add a door sweep or stick-on weatherstripping along the bottom and sides of the door.
Test if your blackout is working
Walk into the nursery at noon with all the blackout in place. Close the door. Stand still for 30 seconds while your eyes adjust. You should be unable to see your own hand at arm's length, or barely see it. If you can see the crib clearly across the room, more sealing is needed.
The other test: hold your phone flashlight up to the outside of the window from outside. Walk inside. If you see the flashlight clearly through the blackout, light is still getting through.
What to do with the dark room
Once the room is dark, you can:
- Push naps later by 15 to 30 minutes (darkness creates the cue to start producing melatonin).
- Solve early-morning wake-ups in 5 to 10 days.
- Lengthen short naps. The 45-minute nap trap often resolves with better blackout.
- Sleep train more effectively. Dark rooms make sleep onset faster.
What about Daylight Savings?
Dark rooms also help with the spring forward and fall back transitions because they decouple sleep from outside light. If your blackout is solid, you may not even feel the time change much. If it isn't, expect 7 to 10 days of disruption per transition.
Common questions
Will too much darkness mess up my baby's circadian rhythm?
No, as long as you expose baby to bright light during morning wake-up and during the day. The circadian rhythm is driven by light contrast. Dark for sleep, bright for wake.
Should I use the same blackout for naps as for nighttime?
Yes. Babies and toddlers nap better in a dark room. There's no benefit to leaving the nursery dim for naps.
What if I share a room with my baby?
Same principles apply. You'll get better sleep too. Add a small clip-on book light to your side of the bed for nighttime reading.