Whilst all blackout blinds look similar at first glance, there is one important feature to look for if you want to ensure your blackout blinds for schools and offices provide adequate room darkening and do not become a costly maintenance nightmare.
Make sure the blackout blind has a ‘zip’ fabric retention feature in the side channels. A correctly installed blackout blind creates an ‘air-lock’ between the window glazing and the room.
Windows left open when the blinds are lowered, windows that leak air, or the opening of a door in an air-tight room can all cause the fabric on a blackout blinds to be blown towards or away from the glazing.
A ‘zip’ fabric retention system stops the fabric from being blown or sucked out of the side channels. Loose fabric means the blind will no longer provide adequate light exclusion. If the blind is operated with the fabric removed from the side channels the fabric will likely tear or become jammed inside the roller cassette.
Working like a zip on a jacket, a fabric retention system consists of a plastic spline welded to the edge of the fabric. This plastic spline slides inside a groove within the side channel as the blind is lowered. This hinders any lateral movement in the fabric.
Torn fabric covers on blackout blinds where the fabric has pulled out of the side channels are the most common problem with blackout blinds. Repair is costly and invasive as a blackout blind is fixed on three sides of the window and sealed in with mastic to give maximum light exclusion. Replacing a fabric cover involves removing the blind entirely from the window.
For further assistance with specifying the correct blackout blind for your project, view our ShadeTech dimout blinds which are all fitted with the LightLock® fabric retention mechanism.