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Application Instructions For Backstop NT For Use Beneath Claddings Other Than Dryvit EIFS DS300 <br /> I.Mixing <br /> A. Open the bucket with a utility knife or lid-off. <br /> B. Backstop NT is ready to use after an initial spin-up using a"Twister"paddle or equivalent mixing blade, <br /> powered by a 1/2 in (12.7 mm)drill, at 450—500 rpm. Do not add cement or any other additives. <br /> C. Do not dilute the product or add any foreign materials to the Backstop NT product. <br /> II.Substrate Check <br /> A. Ensure that the substrate is of a type listed in the Dryvit Backstop NT For Use Beneath Claddings Other Than <br /> Dryvit EIFS Specification, DS200. <br /> B. Ensure that ambient and surface temperatures are minimum 40 °F (4°C)to maximum 100°F(38°C)at the <br /> time of Backstop NT application. <br /> C. Ensure that the substrate is dry. Plywood or OSB moisture content shall not exceed 19% as measured by a <br /> probe type moisture meter. <br /> D. Ensure that the substrate is flat within 1/4 in(6.4 mm) in a 4 ft(1.2 m) radius. <br /> E. Ensure that sheathing gaps do not exceed 1/4 in (6.4 mm). Larger gaps must be corrected by replacing the <br /> sheathing material. <br /> F. Notify the general contractor and/or architect and/or owner of all discrepancies. Do not proceed with work <br /> until discrepancies have been corrected. <br /> G. Ensure that all flashing is installed per the contract documents and in accordance with Dryvit Backstop NT <br /> For Use Beneath Claddings Other Than Dryvit EIFS Specification, DS200. <br /> III. Surface Preparation <br /> A.The substrate shall be prepared so as to be free of foreign materials such as oil, efflorescence, dust, dirt, <br /> paint,wax, water repellents, moisture, frost and any other materials that may inhibit adhesion. Additionally <br /> the surface must be free of loose mortar, wires, or any projections that will not allow a continuous film to be <br /> applied. <br /> B.CMU mortar joints shall be struck flush. Tooled mortar joints and heavily textured CMU, not split faced shall <br /> be skim coated with a non shrinking grout or other concrete patching material. <br /> C. Excess mortar at masonry ties must be removed. <br /> IV. Backstop NT Application <br /> A. Ensure that the wall surface and ambient temperature are from 40 °F (4 °C) minimum to 100°F (38 °C) <br /> maximum at the time of Backstop NT application. WARNING: Do not apply the Dryvit materials in the <br /> rain. The underlying wall materials and substrate surface must be dry prior to applying the air/water- <br /> resistive barrier. <br /> B. Sheathing Substrates: <br /> 1. Prior to applying the Backstop NT over a sheathing substrate, check to ensure that: <br /> a. The sheathing is of a type listed in the Backstop NT Specification, DS200. <br /> b.The sheathing is structurally sound,free of loose material,voids, projections or other conditions that <br /> may interfere with the installation of the Backstop NT material. <br /> c.The sheathing is clean, dry and free of grease, oil, paint and other foreign material. <br /> 1) Exterior grade gypsum sheathing facing paper shall not show signs of deterioration and shall be <br /> firmly bonded to the core. <br /> 2) Plywood or OSB moisture content shall not exceed 19%Wood Moisture Equivalent(WME)as <br /> measured by a probe type moisture meter. <br /> d.SHEATHING WITH GAPS OR DAMAGE EXCEEDING 1/4 IN (6.4 mm)IN ANY ONE DIRECTION <br /> MUST BE REPLACED. NOTE: Notify the general contractor and/or architect and/or owner of all <br /> discrepancies. Do not proceed until all unsatisfactory conditions have been corrected. <br /> e. OSB sheathing requires that joints and fasteners be treated with Backstop NT -Texture. A <br /> minimum of two(2)coats of Backstop NT-Smooth or Backstop NT-Spray are required for the <br /> field of the wall. Backstop NT-Texture is not recommended for application in the field of the <br /> board. <br /> C. Concrete or Masonry Substrates <br /> NOTE: Backstop NT-Texture or Backstop NT-Spray are recommended for use over concrete and <br /> masonry. <br /> 1. Prior to applying the Backstop NT over a concrete or masonry substrate, check to ensure that: <br /> a. All cracks are repaired using appropriate procedures and materials. <br /> b. The substrate is structurally sound,free of loose material,voids, projections or other conditions that <br /> may interfere with the installation of the Backstop NT material. <br /> 3 <br />