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GENERAL GUIDELINES

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            although it is seldom visible. This porosity develops at the   occur, remove old coating before new coatings are applied.
            time of placement from various causes including water   Section 4: Expansion Joints
            content, drying rate, aggregate type and troweling action.
            When elastomeric coatings are placed over concrete, there is   SEALING OF CRACKS, CONSTRUCTION JOINTS,
            a risk that blisters will form from outgassing through surface   SUBSTRATE CHANGES, AND FLASHINGS
            pores. This risk is minimized when using a primer system.  This step, which follows priming and precedes coating, is
                                                                 the most critical stage in the application of Polycoat Products
            Polyprime  should be applied on all concrete and dense   coatings. Success or failure in application of this system
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            aggregate structural concrete.                       depends largely on how they are treated.
            Prime entire deck surface and all vertical or sloping surfaces   Working cracks in concrete are joints or cracks which have
            of curbs, cants, parapets, etc., which are to receive coatings,   moved or will move appreciably, in any or all of the three
            with one coat of Polyprime  applied by roller or spray.  The   dimensions, due to thermal changes or vibration. A crack
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            coverage rate is about 1 gallon/200-300 sqft (0.14-0.20 liters/  which extends at each end to the edge of the surface, to a
            sqm) or 200-300 sqft/gallon.                         building expansion joint or to another working crack may be
            Allow polyurethane primers to dry for one hour or more before   a working crack. A crack with minute broken fragments along
            applying the base coat.                              the edge is probably a working crack.
            Allow epoxy primers to dry until tack free before applying   CONCRETE
            the base coat.                                       To prepare expansion joints, substrate changes, cracks and
                                                                 flashings, apply backer rod if necessary then a polyurethane*
            Note:  Surface temperature is more important than air   sealant and reinforcement tape, embedded into the sealant,
            temperature. The normal minimum surface temperature for   with a stripe coat centered over the crack. The crack must be
            application is 50°F (10°C).
                                                                 fully sealed. Any cracks over 1/16” (0.16 cm) shall be routed
            WOOD                                                 to 1/4” x 1/4”(0.64cm x 0.65cm)  prior to application of sealant
            Polycoat Products polyurethane coatings are self-priming   and reinforcing tape.
            when  applied to  new wood  construction  (primer is  not
            necessary). For optimal adhesion on existing plywood, it is   SUBSTRATE CHANGES
            advisable to use Polyprime .                         Use caulking and reinforcement tape, with a stripe coat
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                                                                 centered over the crack, backer rod and polyurethane* sealant
            STEEL                                                as required at changes in substrate material. Reinforcement
            Wire brush or sand steel surfaces until the metal is bright.   tape must be embedded into the sealant. It is also required
            Solvent wipe after cleaning.                         when the substrate changes plane in a valley, or if a crack
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            Apply Polyprime  at the rate of at a rate of 1 gallon/200-300 sqft   exists at other changes in plane.
            (0.14-0.20 liters/sqm) or 200-300 sqft/gallon. Primer should be   JOINTS IN PLYWOOD
            permitted to dry tack free before applying subsequent coats.   When a joint must be invisible at close range, filling voids and
            Do not exceed recoat window of 12 hours after cure and if   nail heads is necessary. Any wood-adhering, non-shrinking,
            recoat window is passed then solvent wipe the surface with   firm-setting, non-staining material is satisfactory. An epoxy/100
            VOC-compliant solvent and re-prime before proceeding with   mesh sand grout may also be used.
            the next coat/phase.
                                                                 To prepare plywood joints, flashings and substrate changes,
            This ensures proper adhesion under most conditions. Never   apply a  polyurethane*  sealant and  reinforcement tape
            apply Polyprime  to wet or moist surfaces.
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                                                                 embedded into the sealant with a stripe coat centered over
            RECOATING SURFACES                                   supported joints on the same plane, supported joints at
            Decks to be re-coated should be thoroughly cleaned. When   changes in plane, or unsupported joints.
            the area intended for coating has completely dried and is free   Defects in taping and flashing must be corrected prior to
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            of dirt, dust, oil and other contaminants, apply Polyprime .   proceeding with base coats.
            If re-coat window has passed, then solvent wipe the surface
            with VOC-compliant solvent and re-prime with Polyprime  U.  Section 5: Coating Application
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            All coated surfaces require special attention. A test patch   Polycoat Products materials are one or more components,
            should be applied to check for bonding. If adhesion is good,   liquid applied polyurethanes. When properly combined and
            the surface is smooth, and no lifting occurs, apply coating as   applied, they cure to form tough, high strength elastomeric
            specified. If adhesion to substrate is poor, and lifting does   membranes. All specified quantities are minimums and are on




        POLYCOAT PRODUCTS TEL 562.802.8834  |  FAX 562.921.7363                                           Section 1.2
        info@polycoatusa.com  |  www.polycoatusa.com
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