Blackout Curtains That Don’t Off-Gas
My friend was coming to visit and staying in our guest room, which was the perfect excuse to finally make it healthier, more comfortable, and slightly more attractive than it was. I got an organic latex mattress topper, linen sheets, pillows, and the piece de résistance: blackout blinds.
Watch the full video above for the before-and-after, and find all my rated blackout curtain and blind recommendations on the blackout curtains page.
Why do most blackout curtains off-gas?
Standard blackout curtains achieve their light-blocking through a foam or PVC (polyvinyl chloride) backing applied to the back of the fabric. Both materials can off-gas volatile organic compounds (VOCs), and the problem is compounded by the fact that curtains hang in windows, where they get direct sun exposure and heat up, which accelerates off-gassing into your room. You're sleeping near them for eight hours a night, often in a room you keep closed. The combination of heat, enclosed space, and prolonged exposure is what makes non-toxic blackout curtains worth it.
Some blackout curtains use a natural cotton or linen face fabric that looks healthy, but apply acrylic or other plastic coatings underneath to achieve the blackout effect.
What should non-toxic blackout curtains be made of?
The healthiest blackout curtains avoid PVC and foam backing entirely. The realistic options are tightly-woven layered fabric (usually polyester or a polyester-natural fiber blend) with OEKO-TEX certification, which confirms the finished product has been tested for harmful chemical residues including flame retardants. GOTS-certified organic blackout curtains exist but max out at around 95% light blocking — making a 100% blackout curtain from 100% organic natural fiber hasn't been achieved yet. Fabric is surprisingly complicated!
GreenGuard Gold certification is also worth looking for specifically on blackout curtains, more so than for regular fabric, because the off-gassing concern from heat exposure in windows makes VOC testing more relevant here than it is for, say, a sheet.
Do blackout curtains need to block 100% of light?
Not necessarily, but here are two things to consider.
If you need 100% blackout for daytime sleeping, your baby, or have a busy and bright street outside of your bedroom, it’s definitely worth the 100% blackout fabric. Seal the edges so no light gets in, and use a sunrise alarm clock to help signal to your body that it’s morning.
Or, you can use 95% blackout curtains that block the bulk of outdoor light pollution, but without fully sealing the edges — so a sliver of morning sun still gets in. For reference, a streetlamp emits around 50 lux, while direct morning sunlight on a clear day emits around 100,000 lux, so even a small gap will signal your brain it's time to wake up without the full blast.
I personally go with 100% blackout blinds with a very tiny crack for morning light. Then, I use an eye mask and a sunrise alarm clock.
All the rated and ranked options — certified organic, OEKO-TEX certified, suction cup varieties, and DIY blackout fabric are on the blackout curtains page.
