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Selecting materials

When designers develop ideas, the cost of materials can influence the design. The choice of materials needs to works well with the design but must also fit within the product’s budget.

Cost

There are several cost factors in the selection of textiles. The quality of a fabric affects the price - for example, coarser, easy-to-produce cotton is cheaper than labour-intensive silk. Decoration or specialist finishes will also add to the cost.

Calculation of material costs

Fabric is sold by the metre. When making garments, the length needed is worked out using the pattern pieces in their lay plan, which ensures there is minimum waste while still keeping with the direction of the nap. When using a bought pattern, the lengths of fabric for different sizes of the finished garment is written on the back of the envelope.

Example

When cutting material for a T-shirt with a nap or a pattern, more material is needed as the pattern must be cut for the front and back, either side by side or one above the other, rather than having patterns at right angles to each other.

If 4 m of fabric is needed for one dress with a nap, how many metres would be needed for five dresses from material without a nap - provided that the pattern for non-nap material requires 25 per cent less fabric?

4 × 5 = 20 m with nap

25% of 20 m = 20 × 0.25

= 5 m

Material need for without nap = 20 - 5

= 15 m