Blocking out light is a difficult challenge since even the smallest crack of light can look very obvious once your eyes adjust to low light conditions. Also different installation surfaces can dramatically change how effective the blinds can be especially where the bottom sill is out of level or bowed, which is common when they are made of timber.
Our expectation is that Ziptrak Blinds provide very high levels of block out so a person can comfortably sleep during the day. We cannot achieve 100% (Zero light) conditions.
Ziptrak & Stan Bond have worked together to have a number of adds-on items which are sometimes required after initial installation to improve the light block in specific situations.
The most significant light seepage is caused by the reflection of light coloured fabrics and the headbox. As such customers are recommended to have black box & channel along with dark colours fabrics where high levels of blackout are required.