Nonwoven polyester fabric is a fabric formed without spinning and weaving. It is used for building construction. Roof waterproofing is used as bottom cloth.
The exact name should be "nonwovens" or "non-woven fabrics". Because it is a fabric that does not need spinning and weaving, it is made by directionally or randomly bracing the textile short fibers or filament, forming a fiber network structure, and then reinforced by mechanical, thermal, or chemical methods. Non-woven fabric has broken through the traditional textile principle, and has the characteristics of short process, fast production, high production, low cost, wide use and many raw materials.
Industrial non-woven fabrics: filter materials, insulating materials, cement packaging bags, geotextiles, coated fabrics and so on.
Polyester nonwovens: mainly used for building construction, roof waterproofing as bottom cloth, sand, cement and other functions to prevent sand from leaking. Non-woven fabrics are often used in buildings, which is a measure to prevent cracks.

(the above comes from Baidu Encyclopedia)