The industry standard for assessing the suitability for purpose of all upholstery textiles, evaluating their durability in terms of ‘wearability and potential longevity’ through rub tests: i.e. the amount of a rubs/abrasions a fabric can take before it starts to show wear.
This test is carried out by setting a random sample piece of fabric (of approx. 4 cm/1.6”) into a Martindale machine, where it is pulled taut and subjected to a pressure of 12 kpa, being rubbed 10,000 times against oscillating discs of woollen worsted or wire mesh. Once two threads break, or for fabrics such as velvet the pile is worn away and reveals the backing, the machine is stopped and the number of thousands of rubs/cycles recorded. The lower the reference number, the more delicate it is, which dictates what use it is appropriate for:
10,000 or less rubs: decorative uses, such as cushions and accents
10,000-15,000 rubs: curtains and light upholstery
15,000-25,000 rubs: moderate upholstery and loose covers
25,000-30,000 rubs: heavy duty upholstery, general use sofas and for light commercial use
30, 000 rubs and over: commercial grade
40,000 rubs: family sofas
80.000 rubs: heavy commercial use upholstery
The industry suggests 20,000 rubs for normal, family use. However, in my long experience of working on family homes this is too low. The last thing you want to do is to have to replace sofa covers before the children have turned adult, as growing families tend to bring tightened budgets and teenage friends–who are more trouble than sticky toddlers; once they start riding any and all sorts of bikes they traipse round the house and straight to the TV room in grimy trousers… All reasons to do it right in the beginning and it’ll last you fifteen, twenty years.
So long as the initial fabric was good quality, you will be able to eke it out over the period of most wear with throws and new arm-covers. The pounds-per-metre difference between the two qualities represents a very small percentage of the whole investment, when you take into account the cost of one or two lots of making-up labour within the same time frame. Choose heavy weight denim, woven wools, some linens and union cloth. I’ve even used flat weave carpeting for upholstery. There are plenty of bombproof fabrics out there, all you need is their Martindale reference and any additional fabric technical details so you are comfortable with the cleaning, flammability, etc., specifications.
The American version is called the Wyzenbeek test.