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Curtain Weight Calculator — Track Load Capacity
Calculate the weight of finished curtains for track load capacity.
How We Calculate This
Curtain weight is calculated from the total fabric area multiplied by the fabric weight (GSM), plus the lining weight if lined.
The formula
Fabric area = Widths × Fabric width × Cut drop (in m²)
Fabric weight = Area × GSM ÷ 1000 (in kg)
Total weight = Face fabric + Lining + Interlining + Hardware
Lining and interlining are estimated over the same cut area as the face fabric — a slight over-estimate that errs safely for track load. Hardware (rings, hooks, heading tape) adds a fixed allowance, and a safety factor sizes the minimum track capacity.
Frequently Asked Questions
Curtain tracks and poles have weight limits. Exceeding these causes sagging, difficult operation, and potential failure. As a rough guide, lightweight tracks typically hold around 5-10kg and heavy-duty tracks 20-40kg, but real ratings vary widely by brand and fixing — always check the manufacturer specification and treat your fixings as the weak point.
GSM is grams per square metre. It measures fabric weight/density. Lightweight sheers are 50-100 GSM. Medium-weight cottons are 150-250 GSM. Heavy velvets and tapestries are 300-500+ GSM. Check the fabric specification or weigh a sample.
Cut a 10x10cm square and weigh it on kitchen scales. Multiply the weight in grams by 100 to get GSM. For example, a 10x10cm piece weighing 2.5g = 250 GSM. Alternatively, check the fabric bolt or supplier listing.
Standard cotton sateen lining is 100-130 GSM. Blackout lining is typically 180-250 GSM. Thermal lining is 150-200 GSM. Interlining (bump) adds 150-250 GSM on top of the lining weight.
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Last updated: February 2026
All calculations are estimates. Always verify quantities before cutting or purchasing fabric.