When measuring a roller blind to fit into a window recess, we measure the window width and height at their narrowest points. This removes the risk of the blind being too wide or long, thus helping to ensure that it will fit into the recess when it’s manufactured.
From these recess measurements, the manufacturer deducts a small amount from both blind measurements to further avoid the complication of a blind that doesn’t fit into the recess. This blind size deduction is called a blind tolerance.
What happens when a roller blind is too wide?
If a roller blind is too wide it won’t function correctly because the plunger component would become ineffective and the blind would be very difficult to operate. This could then result in chain failure or even fixing failure.
As blind manufacturers, our blinds are made with an in-built tolerance of 10mm as standard. As seen in the image, the fixing plunger on the end of the blind moves by 10mm as a tolerance for when our fitters install the blinds.
What measurements should you provide to your roller blind manufacturer?
If you are providing the measurements of a window recess to a blind manufacturer such as ourselves, it is vital that you let the manufacturer know if the blind measurements you are supplying are the recess size or the actual size you want the blind, with the tolerance already taken into account.
In most cases, our surveyors visit you on site to measure the recesses for you and take full specification notes to ensure minimum fuss and hassle for you and so that we also take ownership of the measurements provided to our manufacturing team.
We manufacture and install roller blinds in education, commercial and health settings throughout the UK. If you would like to speak to a member of our team, please emails email@example.com in the first instance.