Formulated for the tough waterproofing jobs.
Heavy Duty Patching Compound is a thick, black, waterproofing compound manufactured from "Heart of Texas" Asphalt®, High Strength Micro Fibers, Dia-SealTM, finely milled blue-black slate and two highly effective chemical additives, ZHD-7TM and ZonamineTM.

MSDS  Data Sheet

It is used with other SWEPCO Roofing Products in a number of various applications to provide complete roof protection. Consult the appropriate application literature for more information. It is also used as a highly versatile adhesive, sealer and filler in general roof maintenance.
It takes a tough product to provide reliable waterproofing at edge, wall and protrusion flashings. Stresses concentrated in these areas can quickly destroy inferior patching materials. Just as difficult is finding a patching materia that works well in all repair situations . . . tough ones such as blisters, cracks and metal seams. Heavy Duty Patching Compound is the answer for both new roof construction and routine HEAVY DUTY maintenance . . . a heavy-duty, asphalt-base waterproofing mastic, manufactured from specially selected and refined "Heart of Texas" Asphalt, High Strength Micro Fibers, select mineral stabilizers and reinforcers and two special SWEPCO additives which inhibit oxidation and promote better bonding. Used before leaking occurs, Heavy Duty Patching Compound seals, reinforces and waterproofs problem areas.
Superior resistance to cracking

• Heavy Duty Patching Compound
• Versatile, all-purpose fibred patching compound.
• Stays flexible longer.
• Resistant to cracking and splitting.
• Ideal for new or old flashing work and all types of spot repairs
• UV Stable.