Before metrication, UK tape measure blades had only Imperial markings, after metrication they became dual marked with both metric and imperial graduations. Across mainland Europe, tape measure blades have only ever had metric markings.
In addition to measurement graduations UK pocket tape blades are often also marked for imperial construction practices (now only found in older buildings).
For pre-metrication construction work the blade is marked at 16" intervals. This was the standard centre for the timbers in stud wall and roof joists where standard 8' x 4' sheets of plasterboard or timber were used.
Post-metrication the timbers are set at 400 mm centres for use in conjunction with 1200 x 2400 mm standard sheet sizes.
The coatings and treatments that a tape measure blade receives are an important part of ensuring its long and trouble free working life.
After a blade has been printed with its markings a protective coating is applied to provide resistance to wear and tear. The quality of this coating and the process by which it is applied is a key differentiating factor between high and low quality tapes.
Two of the most common types of coating used on pocket tapes (metal bladed) include:
Powder Nylon coating - The blade is first powder coated with Nylon which is then baked on. This is a very durable coating and offers the best combination of quality and cost. The C.K ST tape range has durable Nylon coated blades.
Enamel (lacquer) - Enamel coating is both cheaper and less durable than the Nylon alternative.
Tapes like the Surveyors tape with flexible blades are most frequently Vinyl coated which provides a good compromise between durability and flexibility.