Why is 5mm deducted from the curtain drop?
Speedy Blinds deducts 5mm from a curtain drop because curtains stretch. We make the curtain 5mm short of the ordered drop so that as the fabric settles under its own weight it comes down towards the length that was asked for. The same 5mm comes off a track width so it fits its opening.
On an order for a 2,800mm drop we manufacture to 2,795mm. Over the first weeks of hanging, the fabric relaxes and comes back down to around 2,800mm. If we made it at 2,800mm it would end up long.
The same 5mm deduction applies to track width. On a 3,000mm order the track is made at 2,995mm, so it fits an opening measured to the millimetre.
What this means when a drop is checked
The tolerance is assessed from the manufacturing target, not from the number on the order. On a 2,800mm order the target is 2,795mm, and the ±0.2% standard tolerance is measured from there. The order dimension stays the order dimension; the adjusted figure is what the factory was aiming at.
Where the deduction is not applied
The 5mm drop deduction applies where the drop is measured from the top of the bracket. Where the drop is measured from the top of the fabric to the bottom of the fabric, no further deduction is applied, though the fabric will still settle after hanging.
This answer is general information. For your own windows, your retailer's advice and your order with them come first.
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