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GENERAL GUIDELINES
CONTINUED
SURFACE PREPARATION Plywood must be exterior grade plywood, having either
Concrete or plywood substrates must be free of all tongue-and-groove edges and ends perpendicular to supports.
contamination that may impair proper bonding. Substrates The plywood will be 19/32” (1.50 cm) or 21/32” (1.67 cm) thick.
must be sloped a minimum of 1/4” (0.65 cm) per foot for Plywood should be installed with a maximum of 1/16” (0.16
drainage, and must be primed with the applicable primer cm) space between the plywood sheets and laid over joists
prior to application of the membrane and surface protection on 16” (40.64 cm) centers. Plywood sheets must be screwed
materials.
down securely or nailed with coated annular ring or screw
Concrete: The surface of concrete substrates must be clean shank nails.
and free of standing water. All holes, joints and cracks must If the underside of the joists is covered, the floor/ceiling cavity
be pointed flush with Portland Cement mortar and all high must be vented to aid in drying and to minimize moisture
spots cut or ground off to provide a smooth, even surface. buildup in the deck structure.
Before the material is applied, the substrate must be clean Damaged panels will be repaired/replaced before coating.
and free of dust or foreign material. Paint, grease and oil must
be removed either by grinding or sandblasting and concrete Old plywood must be cleaned and sanded before priming
®
surfaces must be shot blasted or water blasted. Control joints with Polyprime at a rate of 1 gallon/200-300 sqft (0.14-0.20
should be cut per standard concrete construction practices liters/sqm) or 200-300 sqft/gallon prior to coating application.
and caulked. Refer to Technical Data Sheets for proper application rates.
Concrete must exhibit 3000 psi minimum. Concrete surfaces The only acceptable grade of plywood is APA rated, exterior
to be coated must be trowel finished in compliance with grade with exterior glue or better.
the American Concrete Institute standards (except that The appearance and physical characteristics of the plywood
hand troweling is not required), followed by a fine-haired and grade should be considered.
brooming, left free of loose particles, and shall be without Note: The above plywood grade is called out in compliance
ridges, projections, voids and concrete droppings that would with the American Plywood Association’s Standard. Plywood
be mechanically detrimental to coating application or function.
grading which does not reference APA markings may not be
New and Old Concrete: Refer to SSPC-SP13/NACE 6, or ICRI a suitable grade.
03732: CSP 3-5. New concrete must be cured for 28 days prior No liability is assumed by Polycoat Products for defects in
to product application. Surface must be clean, dry, sound the substrate.
and offer sufficient profile for product adhesion. Remove
all dust, dirt, oil, form release agents, curing compounds, PROTECTION OF WORK
salts, efflorescence, laitance and other foreign matter by shot While work is underway and for 72 hours thereafter, traffic
blasting and/or suitable chemical means, in accordance with from other trades should be stopped.
local chemical regulations. Rinse thoroughly, to achieve a pH Material should be stored on plywood or non-asphaltic
between 8.0 and 11.0. Allow to dry completely. If old concrete insulation board.
has a surface that has deteriorated to an unacceptably rough
surface, Polycoat Products PC-260 or a mixture of Polyprime ® Adjacent surfaces which are not to be coated, such as walls,
21 and sand should be used as a repair agent for cracks, spalls, thresholds, fascia, etc., should be carefully masked before
bug holes and voids. Upon full cure of the repair agent, prime priming and coating. Mask vertical surfaces at the line detailed
the entire surface intended for coating. in the architectural drawings or, if none is shown, mask 4”
(10.14 cm) or more up from the deck. When coatings are
Concrete Surface Preparation Reference: applied by spray, caution is necessary, particularly during
windy weather, to prevent overspray damage.
• ASTM D4258 - Standard practice for cleaning concrete
• ASTM D4259 - Standard practice for abrading concrete Section 3: Priming
• ASTM D4260 - Standard practice for etching concrete Polycoat Products elastomeric coatings frequently require
• ASTM F1869 - Standard test method for measuring a primer. The preferred primer varies with the substrate
moisture vapor emission rate of concrete as described below. Guide specifications state primer
• ICRI 03732 - Concrete surface preparation requirements. Product data sheets contain application
instructions.
Neat cement sacking is not an acceptable surface preparation
for coatings. CONCRETE
Sealing Concrete: Most concrete has surface porosity,
Plywood: Plywood should be new or cleaned and sanded.
POLYCOAT PRODUCTS TEL 562.802.8834 | FAX 562.921.7363 Section 1.2
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