Blackout Curtains vs Blinds vs Shutters: Which Blocks the Most Light?

“Blockout” gets thrown around a lot in home furnishing, and half the time it’s not quite true. Plenty of products carry the label and still leave a strip of light sneaking in around the edges, which is all it takes to wake a light sleeper well before the alarm goes off. We looked at the three most common fixes for this and tried to work out which one actually does what it says.

What we’re actually measuring

Light leakage almost always comes down to gaps. Anything that sits inside the window frame rather than sealing against it is going to leave some way through, usually at the sides, the top, or both. So we compared four things for each option: how much light it really blocks, how fussy it is to fit without gaps, what it does for noise and heat (since people ask about these even when they started out just wanting it dark), and what it costs.

One thing worth mentioning before we get into it: your windows aren’t just about light. The Australian Government’s home energy guide puts it plainly, up to 40% of a home’s heating energy can be lost through its windows, and up to 87% of its heat gained comes in through them. Sustainability Victoria’s own research found that shading them properly can cut that heat gain by around half. So whatever you end up with here is doing more than just keeping the room dark at 6am.

Blockout curtains

Fabric, hung in front of the glass, usually with some kind of foam backing or a triple weave to help it along.

• Light: Decent in the middle of the window, not so much at the edges. Even a well-hung curtain usually leaves a centimetre or two of gap down each side and along the top rail, and that’s enough for a thin line of daylight to get through at sunrise.
• Fitting: The easiest of the three by a mile. You can hang these yourself on a weekend, and if you get the colour wrong, swapping them out doesn’t cost much.
• Noise and heat: Not really their job. There’s no air gap behind the fabric, so curtains don’t do much for outside noise or for keeping heat out of the glass.
• Cost: Often under $150 a window for a decent blockout pair, up to a few hundred for something made to measure in a good fabric.

Pros: cheapest option, easy to hang yourself, simple to swap if you don’t like the colour or style.

Cons: light still leaks at the edges even on good ones, does little for noise or heat.

Blinds (venetian, roller or holland)

These sit closer to the glass than curtains do, either inside the recess or just in front of it.

• Light: Depends a lot on which kind. A roller blind in a proper blockout fabric does well, but only if it’s got side channels. Without them, light still gets in down both edges. Venetians are worse for this even when fully closed, because the slats overlap rather than seal.
• Fitting: A little less forgiving than curtains. Get the measurements wrong and the gaps are bigger than they’d be with a curtain hung slightly off.
• Noise and heat: About the same as curtains, for the same reason. They’re close to the glass but there’s no real air gap doing any work.
• Cost: Usually somewhere between $150 and $400 a window once you add side channels or a boxed pelmet, which is what actually stops the leak.

Pros: more control over how much light comes in through the day, mid-range cost.

Cons: real blackout needs side channels, which cost extra, and still does little for noise or heat.

Roller shutters

These go on the outside of the window and roll down over the glass, rather than covering the room side of it.

• Light: This is where they win. Because the shutter sits over the glass itself, with guides down the sides that close off the gaps curtains and blinds can’t avoid, you get close to total darkness. It’s part of why people doing shift work, or anyone trying to sleep during the day, often end up looking at these. Daylight is a lot harder to block out than a streetlight is.
• Fitting: The most involved of the three, and not a weekend job. You’ll generally pay somewhere from $300 to $1,500 a window depending on size and whether it’s manual or electric, and most installers will measure, quote and fit within a week or so. It’s not something that comes with you if you move house, either. We came across a fairly detailed explainer on the different control types while researching this, if you want to go further down that road.
• Noise and heat: Because there’s a sealed air gap between the shutter and the glass, this is the one option of the three that actually does something for noise and heat, not just light. That matters more than you’d think, given how much heat moves through a window. It’s not a clean win, though: you’re paying for three things at once, and that’s worth it if you need all three, and a waste of money if you only need one.
• Cost: The most expensive of the three by a reasonable margin, and not something you’d consider if you’re renting.

Pros: closest thing to total blackout, the only option that also helps with noise and heat.

Cons: highest cost, needs professional installation, not available to renters.

Which option suits your situation?

Main bedroom, street-facing: The most common scenario, and usually the easiest to solve. If you’re a reasonably sound sleeper, a good blockout curtain is often enough on its own. If streetlights, early sunrise or traffic noise are a regular problem, pairing a blind with side channels underneath the curtain closes most of the remaining gaps, and costs a lot less than going straight to shutters.

Nursery or kids’ room: Light control matters more here than almost anywhere else, since daytime naps depend on it as much as nighttime sleep does. A blockout blind with a cordless or motorised mechanism is usually the safer and more practical choice. Corded blinds around cots and young children carry a real strangulation risk, so if you do go with a corded option, make sure it’s compliant with the mandatory safety standard for corded internal window coverings, which covers cord safety in blinds and curtains and applies to anything sold in Australia.

Shift workers’ bedroom: This is where the usual advice flips. Daytime light is far stronger than anything you deal with at night, so curtains and blinds that are “good enough” for normal bedtime routines often aren’t good enough for sleeping at 10am with the sun up. This is the scenario where the extra cost of roller shutters tends to make the most sense, since they’re built to block light at a level the other two options weren’t really designed for.

Rental property: Curtains or blinds are really the only practical options here, since roller shutters are a structural, external installation that most landlords won’t approve and that doesn’t come with you when you move. If light is still a problem in a rental, a tension-rod blockout curtain hung slightly wider than the window frame is a decent workaround that needs no drilling.

Bushfire-prone or high-noise areas: Worth a mention even outside Adelaide specifically. If you’re dealing with both a noise problem (busy road, flight path) and a heat or bushfire-risk issue, this is really the only scenario here where shutters are solving more than one problem at once, which is where their higher cost starts to make more sense relative to curtains or blinds.

So which one do you actually need?

If you’re a fairly sound sleeper and just want something cheap that does a reasonable job, curtains are fine. Want more flexibility through the day as well as darkness at night? Blinds with side channels are a solid middle ground.

And if light, noise and heat are all a problem at once, or you’re sleeping through the day, and you own the place, shutters are really the only one of the three built to handle all three at once. You’re paying a premium for that, so it’s worth being honest with yourself about whether you need the whole package or just part of it.

None of this fixes sleep problems that go beyond light, noise or temperature, by the way. If you’ve sorted the window and you’re still not sleeping well, that’s a conversation for your GP, not a fourth trip to the blinds shop.

— Hannah, lead reviewer