Four-layer Composite roof underlayment also known as a four-layer composite waterproof breathable membrane，It is composed of a layer of polypropylene spunbond non-woven fabric and a layer of woven fabric, which are combined through two coating processes. Both layers of film contain tiny breathable holes, enabling water droplets to be blocked while allowing gases to pass through.It is the most ideal composite roof underlayment.

HY supports the research and production of various types of roof underlayment.The current types include three-layer composite and four-layer composite, as well as the coating composite of non-woven fabric with non-woven fabric and the coating composite of non-woven fabric with woven fabric.

HY supports customized production of various weights, sizes, packaging and logo printing.

HY supports various trade cooperation models, and there is always one that suits you.