SEALGUARD VFI®-993 Silicone Flashing Grade

SEALGUARD VFI®-993 Silicone Flashing Grade

SEALGUARD VFI-993 Silicone Flashing Grade is a single pass, high solids silicone roof mastic. It cures thick and is applied by brush or trowel to seal abnormal, hard-to-reach roof penetrations, large gaps, and areas around parapet walls and HVAC systems. It is also used as a quick and efficient way to seal screw heads and fasteners on several substrates. VFI-993 is designed for use in conjunction with a full commercial roof restoration system or as a repair material to ensure protection from weathering and water infiltration.

SEALGUARD VFI-993 Silicone Flashing Grade from VFI is a high solids roof mastic that seals voids, gaps, and protrusions on commercial roofs.

Features & Benefits

  • 100% silicone – durable protection in areas with leak potential
  • Superior flexibility and hang – hangs on high pitches, vertical surfaces, and parapets without dripping or sagging
  • High build – cures up to ½ inch thick without foaming, enhancing surface protection capabilities
  • Excellent adhesion – no solvents that inhibit adhesion, allowing it to adhere to a variety of substrates
  • Resistant to high temperatures –material will not degrade, allowing for improved roof life expectancy
  • VOC compliant – outperforms EPA-approved standards

Instructions for Use:

Surface Preparation

Make any necessary repairs to the roof components including drains, gutters, flashing, penetrations, etc. All surfaces should be clean, dry, and free of contaminants that might inhibit adhesion. A power washer may be needed for hard to clean areas. More detailed surface preparation will depend on the substrate being coated. Since SEALGUARD VFI-993 Silicone Flashing Grade is recommended for use as part of a full roof restoration systems, it should be applied to the substrate and allowed to cure after spray foams and primers are applied.


SEALGUARD VFI-993 Silicone Flashing Grade should be brought to a minimum temperature of 65°F before application and should be applied when the temperature is between 50°F – 120°F. Rain and moisture cannot be present during application for the mastic to cure properly.

Apply it with a brush or a trowel on areas not easily accessed or areas that need extra protection. VFI-993 can repair most penetrations and protrusions. Use the mastic to fill in stress cracks smaller than ¼”. Add extra material up to an inch around each side of the cracks. Exposed mechanical fasteners must be completely encapsulated with VFI-993, and the fastener base should be sealed to the roof. It should be applied up to ½ inch thick but is specific to each job and type of roof substrate. Check specifications for required wet and dry film thickness.


To clean brushes and trowels used during application, VFI recommends using mineral spirits. Since VFI-993 is composed of silicone, you should not wash equipment with water as it will cure with moisture.


*Always read the safety data sheet before working with chemicals

Use chemicals only as directed and for their intended purpose. Do not dispose of chemicals down the drain. Most chemicals must be disposed of as hazardous waste.

PPE to avoid all unnecessary exposure:

  • Eye protection – wear safety glasses and any additional eye protection as necessary
  • Hand protection – wear chemically resistant protective gloves (nitrile, butyl, or neoprene)
  • Skin and body protection – wear suitable protective clothing
  • Respiratory protection – in case of insufficient ventilation, wear suitable respiratory equipment. Respirator selection must be based on known or anticipated exposure levels, the hazards of the product, and the safe working limits of the selected respirator

Product Limitations

  • Incompatible materials – oxidizers
  • Conditions to avoid – heat and incompatible materials
  • Chemical stability – stable under normal storage conditions
  • Reactivity and hazardous reactions – no dangerous reaction known under normal use
  • Hazardous decomposition products – may include, and are not limited to, oxides of carbon

Potential Health Hazards

  • May cause respiratory tract irritation.
  • May cause stomach distress, nausea, or vomiting if swallowed.
  • May cause skin irritation and sensitization: redness, drying, defatting, and cracking of the skin.
  • May cause eye irritation: discomfort, pain, redness, swelling, excess blinking & tear production.

*If you are experiencing any of these symptoms, seek medical advice or attention. Call a poison control center or doctor if swallowed.

Application Methods:

  • Chip Brush Chip Brush
  • Brush Brush
  • Trowel Trowel

Available Packaging:

  • 5 Gallon
  • 2 Gallon
  • 1 Gallon