What is Blackout vs room-darkening vs sheer?
Blackout blocks ~99% of light (usually a 3-pass coated or triple-weave fabric); room-darkening blocks 70–90%; sheers only diffuse.
Short answer
Light leaks around the edges — the rod must extend 15–20 cm beyond the window on each side.
Blackout vs room-darkening vs sheer when buying a curtains & blinds
Blackout blocks ~99% of light (usually a 3-pass coated or triple-weave fabric); room-darkening blocks 70–90%; sheers only diffuse.
Why it matters: Only true blackout gets a west-facing bedroom dark enough for day sleep or a baby's nap.
Look for: Light leaks around the edges — the rod must extend 15–20 cm beyond the window on each side.
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