Titanium TITANIUM™ Synthetic Roofing Underlayments are highly engineered, mechanically attached, coated woven underlayments for sloped roofs.TITANIUM™ underlayments represent the future in felt replacement technology, and used in conjunction with TITANIUM™ peel and stick self adhered underlayments (PSU), offer the sloped roofing industry a truly revolutionary system of safety, security and simplicity.