Blackout Curtains: How to Make a Room Truly Dark

One of our strongest picks is the Eclipse Palisade Blackout Curtain Panel, a standout in our Best Blackout Curtains for Bright Bedrooms list. The Exclusive Home Curtains Catarina Layered Blackout and Sheer Curtain Panel Pair is another excellent choice.

Start with your main use and budget, then compare our shortlists: Best Blackout Curtains for Bright Bedrooms, Best Blackout Curtains for Nurseries, Best Blackout Curtains for Shift Workers.

Look for panels described as 100% blackout or with a coated or lined back if you need full darkness for day sleep or a home theater. Room-darkening fabric is fine for general privacy.

The backing material matters most. A foam-laminated or triple-weave backing, like Eclipse's Thermaback construction, blocks a higher percentage of direct light than a plain woven or sateen fabric, which typically tops out around 90% to 95% blocking even in a dark color. For a room with unobstructed direct sun for several hours a day, that difference between 95% and 99% blocking is very noticeable.

The same backing that blocks light also reflects and insulates against radiant heat, and most blackout curtain brands advertise a specific energy-loss reduction figure, commonly in the 25% range, from reduced heat transfer through the window. A sun-facing bedroom that runs several degrees warmer in the afternoon will typically feel a real difference with a properly fitted blackout curtain closed during peak sun.

Darker colors block more light at a given fabric weight and backing type, generally 3 to 5 percentage points more than the same product in a light color. For a bedroom that gets strong direct sun, a dark color (navy, charcoal, black) combined with a laminated backing gives the most complete blocking. Lighter colors still work but may need a second layer for a genuinely dark room at midday.

Some fading over time is normal for any fabric exposed to direct UV for years, and darker colors tend to show fading more visibly than lighter ones since the contrast between faded and unfaded fabric is more obvious. Look for curtains explicitly rated to block UV rays, which most name-brand blackout curtains do, and consider a curtain liner or UV-filtering window film for the most sun-exposed windows.

For most babies, yes, though the effect varies by child. A dark room removes one of the environmental cues (daylight) that can cut a daytime nap short, especially for naps scheduled during peak sunlight hours. Pediatric sleep consultants commonly recommend blackout curtains or shades as a low-cost first step for babies who wake up at the first hint of light in the room, alongside a consistent nap schedule.