True blackout performance comes from where the brackets go, not just the fabric. Outside mount with side channels eliminates light bleed at the edges — here's the full process.
Difficulty: Moderate. Time required: 30–60 minutes per window.
Prepare your tools: Drill, spirit level, pencil, screwdriver, measuring tape, wood and masonry bits, and wall plugs if mounting into masonry.
Choose your mount: Blockout blinds work best as an outside mount, extending at least 75–100 mm beyond the window frame on all sides to minimise light bleed. Inside mounts will always allow some side light gap unless side channels are added.
Consider side channels (optional): For true blackout, side channels or reveal strips can be installed on the left and right of the recess to eliminate edge light gaps. Mark side channel positions before drilling brackets — they affect bracket placement.
Mark and drill bracket positions: Mark bracket positions using a spirit level. For outside mounts, extend at least 75 mm beyond the frame. Pre-drill pilot holes and secure brackets firmly.
Install side channels (if using): Snap or screw the side channels into position on the left and right of the recess. Use a spirit level to confirm both channels are perfectly vertical.
Insert the blind: Slide the roller tube into the brackets — pin end into the pin bracket, motor or chain end into the motor bracket. If side channels are installed, confirm the fabric edges slide freely inside the channels.
Test full drop and retraction: Lower the blind to its full drop and check that both edges sit inside the side channels (if installed). Raise and lower several times to confirm smooth operation with no fabric binding.
Secure control cord: Attach the chain or cord to the child-safety anchor point. Never leave cords loose.
For true blackout performance, outside mount with side channels is strongly recommended. Inside mounts without side channels will always allow some light bleed at the edges regardless of fabric. Child-safety cords must always be secured to the anchor point.
No. Even with the densest blockout fabric, an inside mount leaves a small light gap on each side. Outside mount with side channels is the only way to fully eliminate edge light.
Only if you want true blackout — bedrooms, nurseries and home cinemas. For general privacy or glare reduction, brackets alone are fine.
Aim for 75–100 mm past each edge. Below 75 mm, daylight will wrap around the fabric and visible light bleed returns.
Sometimes — the fabric width has to allow for the channel insertion. Confirm with us before ordering channels separately.