Foster® 40-20C Protective Coating

1 of 92 products in this brand
Foster® 40-20C Protective Coating offers a resilient and decorative finish that accommodates movement without creating spaces for bacteria to lodge. This cost-effective coating is resistant to various industrial chemicals and provides long-lasting protection. It is suitable for application on walls, ceilings, pipes, both interior and exterior surfaces of HVAC duct systems, and in areas where effective controls are required.

Product Type: Coating

Features: Bacteria Resistant, Chemical Resistant, Cost Effective, Fungus Resistant, Good Toughness, High Elasticity, Long Term Protection, Mildew Resistant, Mold Resistance, Stain Resistant

Application Area: Ceilings, HVAC Ducts, Pipes, Wall

Compatible Substrates & Surfaces: Metal, Painted Surfaces, Wood

Application Method: Brush, Spray

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Identification & Functionality

Features & Benefits

Ready-to-Use Product Features
Product Highlights
  • 40-20C Protective Coating provides a cost effective, decorative finish resistant to many industrial chemicals, together with long- lasting protection.
  • It can be used on walls, ceilings, pipes, interior and exterior surfaces of HVAC duct systems and wherever effective controls are essential.
  • 40-20C resists mold, fungus, discoloration from mildew and stains by mold. 40-20C has been formulated with an EPA-registered fungicide to resist mildew growth.
  • Its extremely high level of resistance enhances the longevity of the material. 40-20C 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 Area
Application Method
Compatible Substrates & Surfaces
  • Protect from freezing.
  • Do not apply near food stuffs in unventilated areas.
  • Ensure product is dry before returning food to area.
  • Always ensure adequate ventilation.
  • Do not store or apply over 100°F (38°C) or below 40°F (4.4°C).
  • Water-based products may corrode carbon steel spray equipment.
  • Corrosion resistant pumps and fittings are suggested.
  • This product does not protect users or others against bacteria, viruses, germs or other disease organisms.
  • It does not take the place of normal cleaning & disinfecting procedures.
  • For professional use only.
Preparation and Application Information

Material Preparation

  • Do Not Thin.
  • Keep container closed when not in use.
  • Do not apply outdoors in damp or rainy weather.

Surface Preparation

  • Unpainted brick, plaster and cement-based surfaces: Apply only to clean, dry surfaces free of all dirt, grease or impurities. On mold-infested surfaces, aggressively scrape the surface, then wire brush to produce a firm, sound substrate. Wash the intended surface with a detergent and water solution following the instructions for its use, then rinse and allow to dry completely before proceeding. 40-20C may be applied directly without the need for primer. For improved adhesion to unpainted brick, plaster and cement-based surfaces, prime with a water-based primer and fill gaps with block filler.
  • Painted surfaces: Wire brush painted surfaces, removing all flaking, loose or chalking material. Sand all glossy surfaces (alkyl, oil, epoxy-based coatings, etc.) to roughen entire area. Wash the intended surface with a detergent and water solution following the manufacturer’s instructions for its use, then rinse and allow to dry thoroughly.
  • Metal surfaces: Remove any dust, grease, oil or materials. Abrade all surfaces to remove all surface rust. Wash the intended surface with detergent and water, then rinse and allow to dry thoroughly. Where metal will be exposed or potential exists for the coating to be peeled from the surface, prime metal surfaces with a water-based, adhesion promoting primer suitable for the type of metal to be coated.
  • Wooden surfaces (unpainted): Remove all dirt, grease, oil or materials. Remove all loose substrate materials, unnatural protrusions, splintered materials, etc. to a sound surface. Wash with detergent and water following the manufacturer’s directions, then rinse and allow to dry thoroughly. 40- 20C may be applied directly without the need for primer. On exposed surfaces where staining or discoloration of the coating would be objectionable, prime with a water-based, stain blocking primer.
  • HVAC systems: Always follow industry accepted cleaning procedures. Galvanized surfaces need to be vacuumed or washed clean of all accumulated mold, dust and loose particles. Ensure that all interior surfaces are thoroughly dry before applying Foster® 40-20C. Follow recommendations above for metal surfaces. Lined air ducts must be lightly vacuum cleaned to remove all mold, dust and loose particles, being careful not to tear or loosen the liner.


  •  Always ensure adequate ventilation. HVAC systems must be under negative air pressure during and after application to allow for exhausting of odors and rapid drying of the coating.
  • Apply 40-20C to all surfaces by brush, roller or airless spray at a rate of approximately 1.25 gal. per 100 square feet.
  • Brushing or rolling will require two coats applied at 90° to each other.
  • Under normal circumstances, a spray application can be completed in one coat, but for extremely porous or irregular surfaces, a second coat may be required.
  • Ensure that the finished surface is smooth and homogeneous.
  • For airless spray application, use an electric 2800 psi minimum pump with a 0.021 – 0.025 fluid tip.
  • Note
    • Continue to circulate fresh, dry air throughout the area during the application and for as long after the application as is possible.
    • Exhaust circulated air outside the building or occupied space.
    • If air must be exhausted inside the building, circulate air through an air scrubbing filtration system with odor absorbing medium, such as a charcoal medium.
    • This circulation and filtration helps to reduce the dry time of the coating and reduce latex- type odors that could possibly migrate from the application area.
    • Be sure exhausted air is odorless before venting into occupied spaces.


  • Wash down periodically with mild detergent and water.
  • Where severely contaminated, scrub clean using steam cleaning where permissible.
  • Normal cleaning procedures must be maintained in HVAC systems to remove accumulated airborne particles.
  • If coating becomes damaged, clean surface and re-apply coating.
Cleaning Information

Use fresh water to clean brushes and equipment before product dries. Dry product may be removed with chlorinated solvents (non-flammable) or xylol (flammable).


Physical Form
Typical Properties
ValueUnitsTest Method / Conditions
Average Weight11.9lbs.ASTM D1475
Average Non-Volatile (by Volume)58.0% ASTM D2369
Drying Time (Set to Touch)4.0Hours-
Drying Time (Dry Through)16.0Hours-
Coverage Range ¹1.25gal./100 sq. ft.
Wet Flammability99.0°C-
Water Vapor Permeance (at 100°F, 90% RH, 0.011 in)6permsASTM F1249
Water Vapor Permeance (at 100°F, 90% RH, 0.28 mm)4metric permsASTM F1249
Application Properties
ValueUnitsTest Method / Conditions
Service Temperature Limits (at coated surface)-20 to 200°F
Flame Characteristics
ValueUnitsTest Method / Conditions
Flame Spread ²15ASTM E84
Smoke Developed ²5ASTM E84

¹ - Wet coverages shown are for smooth, non-porous surfaces. Porous or rough surfaces may require higher gallonage to obtain required dry thickness.

2 - Tested at a coverage rate of 80 sq. ft./gal. (1.96 m2 /l). Applied to inorganic reinforced cement board. The flame spread may vary at different product thicknesses and/or when applied over other surfaces.

Regulatory & Compliance

Storage & Handling

Shelf Life
12 months