When constructing a multi-layer flat roofing system, the quality of the foundation determines the longevity of the entire roof. The G.A.P. #43 Organic Base Sheet from A1A Wholesale Supply is engineered to provide that essential structural stability. This base sheet is manufactured to meet the rigorous ASTM D2626 standards, ensuring it can withstand the thermal and physical stresses common in professional roofing environments.

By coating the saturated organic felt on both sides with weathering-grade asphalt, G.A.P. creates a dense, moisture-proof barrier that serves as the perfect substrate for hot-mopped or cold-applied Built-Up Roofing systems. The addition of mineral surface fines prevents the material from sticking in the roll, even in high-heat warehouse or job site conditions, ensuring a smooth and efficient installation every time.

Product Details

• Manufacturer: G.A.P. Roofing, Inc.

• Material: Saturated organic felt with dual-sided weathering-grade asphalt coating.

• Finish: Mineral surface fines (to prevent sticking).

• Classification: ASTM D2626-04.

• Code Approval: Florida Building Code Approved.

• Roll Dimensions: 36″ wide.

• Coverage: 216 sq. ft. (2 Squares) per roll.

• Weight: Heavy-duty at 76 lbs per roll.

• Logistics: 25 rolls per pallet / 24 pallets per truckload.

Features & Benefits

• Double-Coated Protection: Asphalt coating on both sides provides superior waterproofing and increased resistance to environmental degradation.

• Heavyweight Stability: At 76 lbs per roll, this base sheet offers a rigid, flat-laying surface that reduces the risk of buckling under subsequent roofing layers.

• Superior Adhesion: Specifically designed to provide an ideal bonding surface for hot asphalt, cold adhesives, or lap cements used in BUR systems.

• Weathering-Grade Quality: Uses premium coating asphalt to ensure the base layer maintains its integrity throughout the life of the roof.

• Contractor-Friendly: The mineral surface ensures easy unrolling and handling, even in the humid climates common across Florida and the Gulf Coast.

Applications

• Built-Up Roofing (BUR): The primary base layer for multi-ply asphalt roofing systems.

• Flat Roof Decks: Applied directly over wood decks or approved insulation boards.

• Commercial & Residential: Suitable for low-slope commercial buildings, residential “Florida rooms,” and porch transitions.

• System Component: Often used as a high-strength underlayment in specialized multi-layered waterproofing assemblies.

Technical Specifications & Logistics