Foster® 40-25™ Full Defense™

Surface Preparation

Apply only to surfaces free of all loose dirt, grease, mold or other materials that may interfere with the adhesion of the coating to the substrate.

Masonry, brick, plaster and cement-based surfaces: On mold-infested surfaces, aggressively scrape the surface, then wire brush to produce a firm, sound substrate. Clean the intended surface of any materials that may interfere with the adhesion of the coating and allow to dry completely before proceeding. Prime all unpainted brick, plaster and cement-based surfaces with a masonry sealer or primer if dusty. A block filler may be used to patch and smooth porous surfaces.

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. Alternately, a primer may be applied to glossy surfaces to improve adhesion; adequate adhesion must be confirmed prior to completing application. Clean the intended surface of any materials that may interfere with the adhesion of the coating and allow to dry completely before proceeding.

Metal surfaces: Remove any dust, grease, oil or materials. Abrade all surfaces to remove all surface rust. Clean the intended surface of any materials that may interfere with the adhesion of the coating and allow to dry completely before proceeding. All rusted, metal surfaces must be primed before application of Foster® Full Defense™. Foster® Full Defense™ may be applied directly onto cleaned, unrusted, galvanized surfaces.

Unpainted wood and drywall: Remove all dirt, grease, oil, loose mold or mildew or other materials. Remove all loose substrate materials, unnatural protrusions, splintered materials, etc. to a sound surface. In wall cavities or unexposed surfaces, Foster® Full Defense™ 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 stain blocking primer.

HVAC systems: Follow use directions provided in the supplemental document “Application of Full Defense™ Fungicidal Protective Coating, 40-25, in HVAC Systems” available at www.fosterproducts.com. Always follow industry accepted cleaning procedures. Lined air ducts must be lightly vacuumed to remove all mold, dust and loose particles, being careful not to tear or loosen the liner. 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® Full Defense™. See metal surface preparations for primer requirements.

Application

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 Foster® Full Defense™ to all surfaces by brush or airless spray at the following wet coverage rates (rates are minimum required and are subject to the nature of the material being coated):

• Galvanized Metal: 0.75 gal./100 sq. ft. (0.31 l/m2);
• New Duct Liner: 1.0 gal./100 sq. ft. (0.41 l/m2);
• Old Eroded Duct Liner: 1.5 gal./100 sq. ft. (0.61 l/m2);
• Wood, Drywall, OSB: 0.33 gal./100 sq. ft. (0.14 l/m2)

Unsealed, rough or low-density surfaces may require more material to attain required surface sealing. Brushing will require two heavy 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 well-sealed. For airless spray application, use an electric 2800 psi minimum pump with a 0.015 – 0.025 fluid tip. Clean brushes and equipment with warm water before product dries.

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.