Synthetic Roofing Underlayment
Roofing Underlayment Manufacturer
KOSITE supplies synthetic roofing underlayment and waterproof roof-membrane roll goods for roof-deck protection, OEM programs and export packing.
UseRoof deck and underlayment protection
GSM / Basis Weight100-260 gsm, selected by roof system and strength requirement
Roll WidthCommon 1.0-1.5 m; custom width by order
Roll Length50 m, 100 m or custom roll length
SurfaceSmooth, anti-slip or printed surface option
FunctionWater-resistant roof membrane support
SupplyRoll goods with export packing options
SupportSamples, data sheet and quotation follow-up
Where Synthetic Roofing Underlayment Fits
- Used below the final roof covering as a secondary water-management layer for roof-deck protection.
- Suitable roll construction depends on the roof profile, slope, installation method and expected exposure before covering.
- GSM, roll format, surface, printing and export packing can be set for distributor, contractor and OEM programs.
How to Select Roofing Underlayment
- Roofing underlayment must be selected as part of the roof build-up, not only by basis weight. Roof deck, covering profile, insulation position and temporary exposure affect the choice.
- Compare water resistance, tensile and tear strength, surface grip, roll handling and fastening method for the intended roof system.
- Laps, edge details, penetrations and compatible tapes or flashings determine whether the installed underlayment remains continuous.
Roofing Underlayment Specification Checklist
- Confirm the roof build-up, roof slope, covering profile, insulation position and expected exposure before selecting a roll structure.
- Specify the required water resistance, vapor behavior, tensile strength, tear strength and surface-finish requirements.
- Set roll width, roll length, core size, printing, label and pallet or container-packing requirements.
- Review lap direction, fixing method, edge treatment, penetrations and compatible tape or flashing before installation.
- Confirm applicable product data, test references and destination-market requirements before production.
- Approve a sample before bulk supply, especially for private-label or project-specific programs.
Related Technical Resources
Use these application notes with the selected product data sheet and project specification.
Breathable Roofing Underlayment for Metal Roof Systems
Roof-system selection, overlap, fastening and supply checks for underlayment buyers.
Why Installation Details Matter
Practical guidance for overlaps, penetrations, repairs and compatible accessories.
Waterproof Breathable Membrane Storage and Handling
Protect roll condition during warehouse storage, transport and site handling.