Most nursery checklists cover what goes into the room. This one covers the room itself: how warm it gets, how damp it feels, how loud it is at 2 a.m., where the air comes from, and how dark it gets. Those are the parts that are hard to change once the baby is home.
Work through it a few weeks before the due date. Paint and furniture take a weekend; finding out the room runs four degrees hot at night, and fixing it, can take longer.
The short version
- Temperature: most US guidance says 68–72°F; the UK says 16–20°C (61–68°F). Measure at the crib.
- Humidity: the EPA recommends below 60%, ideally 30–50%.
- Sound: know what any fan, AC or purifier reads on the speed you’ll use overnight.
- Air: nothing blowing directly on the crib; filtration sized to the room if you want it.
- Light: blackout on west and south glass, closed by early afternoon on hot days.
1. Temperature
- Put a room thermometer near the crib, out of direct sun.
- Read it at 4 p.m., at bedtime and around 2 a.m. for a few nights, including a warm one.
- Compare it with the thermostat. A gap of more than a couple of degrees means the room isn’t being controlled by the system.
- Know your target: most US guidance gives 68–72°F; the AAP’s emphasis is avoiding overheating and dressing the baby in one more layer than you’d wear.
The full background is in what temperature a baby’s room should be. If the room runs hot upstairs, see why the upstairs nursery is so hot.
2. Humidity
- Get a hygrometer (many room thermometers include one).
- Aim for 30–50% relative humidity, the EPA’s recommended range, and keep it below 60%.
- Check for signs of moisture: condensation on window frames, a musty smell, or marks in corners. The EPA’s mold guidance says to fix the moisture source first.
- In Los Angeles, check again during a Santa Ana wind, when indoor air can turn very dry.
3. Sound
- Stand by the crib with every fan, AC and purifier running on its overnight setting. Listen for hums, rattles and cycling.
- Look up the manufacturer’s sound rating for that speed, not just the lowest number on the box.
- Note outside noise too: a neighbor’s condenser, a street-facing window.
How a mini split and a window unit compare on sound: mini split vs window unit for a nursery.
4. Air and airflow
- Make sure no vent, fan or AC blows directly across the crib.
- Close the door with the system running. If the room gets stuffy, it may need a return-air path.
- If you want cleaner-feeling air, choose a portable purifier by its CADR and CARB certification. See how to choose an air purifier for a nursery.
- Skip anything that produces ozone; the EPA advises against ozone generators.
5. Light and windows
- Blackout blinds or curtains on any west- or south-facing glass.
- Cordless blinds, or cords tied up well out of reach.
- Close them by early afternoon on hot days to keep the sun’s heat out before bedtime.
6. Placement
- Crib away from windows, vents and the direct airflow of any unit.
- Thermometer, monitor and purifier out of reach, with cords secured behind furniture.
- Follow the AAP’s safe sleep guidance for the crib itself: firm, flat, and clear of loose bedding.
When to do what
| When | Room task |
|---|---|
| Early | Measure temperature and humidity at the crib for a week, including a warm night. Book an assessment if the numbers drift. |
| Several weeks out | Make any equipment decision. Installs that need a permit take time to schedule. |
| A few weeks out | Blinds, purifier, cords, crib placement. Run everything overnight once and listen. |
| The last week | Re-check temperature and humidity at bedtime and 2 a.m. Adjust layers, not just the thermostat. |
How Little Lungs helps with the room
The Free Air Check covers the first four sections of this list in one visit: we measure temperature and humidity at crib height against the thermostat, check airflow and sound, and tell you plainly what, if anything, the room needs before the baby arrives. If it does need equipment, see what size mini split a child’s room needs and what it costs in Los Angeles.
Questions parents ask
When should I start preparing the nursery?
Give the room itself a few weeks of lead time before the due date. Furniture and paint are quick; testing how the room holds temperature overnight, and fixing it if it doesn’t, takes longer, especially if equipment or a permit is involved.
What temperature and humidity should a nursery be?
Most US guidance puts a baby’s room at 68 to 72°F; the UK’s Lullaby Trust recommends 16 to 20°C. The EPA recommends indoor relative humidity below 60%, ideally 30 to 50%. The AAP advises against overheating and does not set a single number.
What should be in a nursery for safe sleep?
Follow the American Academy of Pediatrics’ safe sleep guidance for the crib itself. This checklist covers the room around it: temperature, humidity, airflow, sound, light and where equipment sits.
Get the room checked before the baby comes
One visit, a measured room, and a plain answer about what it needs.
Sources
- American Academy of Pediatrics — How to Keep Your Sleeping Baby Safe
- The Lullaby Trust — Room temperature
- U.S. EPA — A Brief Guide to Mold, Moisture, and Your Home
- U.S. EPA — Guide to Air Cleaners in the Home
This checklist covers the room’s comfort and climate. For questions about your baby’s health or sleep safety, talk with your pediatrician.
