Foster® Sealfas® Coating 30-36™

1 of 184 products in this brand
Foster® Sealfas® Coating 30-36™ is a white, fire-resistant indoor coating designed for thermal insulation. It also serves as an adhesive for canvas and glass lagging cloth when used for lagging and laps. This coating offers excellent brushing characteristics, ensuring better coverage and uniformly coated surfaces. It maintains a clean white finish that does not yellow or discolor with age. The surface can be easily washed to remove grease, oil, soot, and other dirt accumulation.

Product Type: Coating, Sealant, Waterborne Coating, Waterborne Sealant

Features: Abrasion Resistant, Fire-Resistant, Good Toughness, Water-based

Compatible Substrates & Surfaces: Polystyrene (PS) Foam, Polyurethane (PU) Foam, Woven Fabric

Application Method: Brush, Spray

Enhanced TDS

Identification & Functionality

Features & Benefits

Product Highlights
  • Foster® Sealfas® Coating is a white, fire-resistive, tough, washable, abrasion-resistant indoor coating for thermal insulation.
  • It is also used as a lagging and lap adhesive for canvas and glass lagging cloth.
  • It has excellent brushing characteristics, which will result in better coverage, and more uniformly coated surfaces.
  • It presents a neat white finish, and will not yellow or become discolored with age.
  • The surface can be washed free of grease, oil, soot and other dirt accumulation.
  • Sealfas® Coating provides a protective finish for insulation on air conditioning ducts and cold water piping when applied in 2 coats with reinforcing fabric embedded between coats.
  • When relative humidity exceeds 75% for continuous periods, or where the insulated piping or equipment contains chilled water, brine or refrigerant, additional vapor barrier protection is suggested.
  • Sealfas® Coating is compatible with polystyrene and polyurethane foam insulations.
  • It may be applied to the joint or edges of fibrous duct liner insulations to seal and prevent air erosion.
  • Sealfas® Coating meets the requirements of Military Specification MIL-A-3316C Class 1, Grade A.
  • Select Foster 30-36 HF Sealfas® Coating where MIL-DTL- 3316D, Class 1 Grade A and listing on the MIL-3316 QPD are required.
  • Sealfas® Coating is approved by the U.S. Coast Guard under 164.012.
  • Sealfas® Coating is produced under the classification and follow-up service of Underwriter’s Laboratories, Inc. and meets NFPA 90A and 90B 25/50 requirements.
  • Sealfas® Coating contains no asbestos, lead, mercury or mercury compounds.
  • Sealfas® Coating 30-36™ meets the requirements of:
    • MAS Certified Green®
    • California Dept. of Public Health Standard Method v1.2
    • VOC Emissions and Content requirements to contribute to LEED v4 EQ Credit: Low Emitting Materials – Paints and Coatings
    • Collaborative for High Performance Schools EQ 7.1

Applications & Uses

Application Method
Preparation and Application Information


  • Do not thin.
  • Apply only to clean, dry, oil-free surfaces.
  • Keep container closed when not in use.


  • Apply a tack coat of Foster® Sealfas® Coating at 60 – 70 sq. ft. per gal. (1.5 – 1.7 m2/l).
  • Immediately imbed the selected lagging fabric into the wet coating. Smooth to avoid wrinkles and overlap seams by at least 2 inches (5 cm).
  • Immediately apply a finish coat at 60 – 70 sq. ft. per gal. (1.5 – 1.7 m2/l). The dry film thickness of this application will vary with the fabric selected.
  • For air conditioning ducts, increase the coverage rate to 40 – 50 sq. ft. per gal. (1.0 – 1.2 m2/l) for each coat.


  • Use clean paint brushes (suitable for water-based paints).
  • Apply with full brush and spread out evenly.


  • Sealfas® Coating may be airless spray applied.
  • For spray equipment information please consult Airless Spray Recommendations or contact your airless spray equipment supplier.
  • Average viscosity range: 55,000 – 75,000 cps.
  • Corrosion resistant pumps and fittings are suggested.

Top coating

  • If Sealfas® Coating 30-36™ is to be top coated with anything other than an alkyd enamel conforming to DOD-E-24607 as specified in MIL-A-3316C, the user must confirm by his own tests that the products are compatible and that the final results are satisfactory.
Cleaning Information
  • Use clean fresh water for cleaning brushes and equipment before product dries.
  • Dry product may be removed with hot soapy water or strong solvents such as chlorinated solvent (non-flammable) or mineral spirits (flammable).


Physical Form
Typical Properties
ValueUnitsTest Method / Conditions
Average Weight / U.S. Gallon1.25kg/lASTM D1475
Average Non-Volatile (by Volume)40.0% ASTM D2369
Average Non-Volatile (by Weight)51.0% ASTM D2369
Coverage Range40 - 70sq. ft./gal.-
Drying Time (Set to Touch)2.0Hours-
Drying Time (Dry Through)15.0Hours-
Water Vapor Permeance0.5 - 1.5PermsASTM F1249
Wet Flammability100.0°C-
Application Properties
ValueUnitsTest Method / Conditions
Service Temperature Range-18 to 82°C-
Flame Characteristics
ValueUnitsTest Method / Conditions
Surface Flame Spread10.0-ASTM E84
Smoke Developed5.0-ASTM E84

Regulatory & Compliance

Storage & Handling

Shelf Life
12 months
Handling Conditions
  • Store and apply between 4°C and 38°C, protect from freezing until dry.
  • Always test foil and paper facings for acceptable adhesion before using.