Radial

Crosscut and radial sails are in many cases made from the same material in the form of woven polyester. This material is also known as Dacron.

But radial shapes are often also used for the next step up on the ladder in terms of materials as this layout works well with laminates, too. 

The difference between crosscut and radial sails comes down to the design - and where crosscut sails are more effective to produce in terms of materials used, the shape of a radial sail causes more sailcloth to be cut away - but on the other hand, the final product also offers better performance and a longer-lasting shape. 

This is also one of the reasons why this layout is often combined with laminates to make the most of the more expensive raw materials involved. 

The main difference in terms of the layout is that a radial layout is a design with more dimensional stability thanks to the way the load on the sail is spread.

This comes through the layout as the sail is assembled down the middle to keep the shape better, and because it has this shape, it also distributes the load of the sail to the tacks or corners better.

This is an integral part of constructing the sail, so the sailmaker will always put the webs in the direction where the cloth is most stable - and when combined with laminate materials, you get all the advantages plus a sail which will be less prone to stretching than Dacron ultimately is. 

An added bonus is also that the sails generally are lighter than what you would get on an equivalent sail in a crosscut layout.