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Backstop NT For Use Beneath Claddings Other Than Dryvit EIFS Specifications DS200 2.02 COMPONENTS A.Air/Water-Resistive Barrier Components: 1. Dryvit Backstop NT: A flexible, polymer-based, noncementitious,water-resistive membrane and air barrier available in Texture, Smooth, and Spray. 2. Dryvit Grid TapeTM:An open weave fiberglass mesh tape with pressure sensitive adhesive available in rolls 4 in(102 mm)wide by 100 yds (91 m) long. B. Flashing Materials: Used to protect substrate edges at terminations. 1. Liquid Applied:An extremely flexible water-based polymer material, ready for use. a. Shall be AquaFlash®Liquid and AquaFlash Mesh 2. Sheet Type: a. Shall be Flashing Tape and Surface Conditioner 1) Dryvit Flashing Tapee°.A high density polyethylene film backed with a rubberized asphalt adhesive available in rolls 4 in(102 mm), 6 in (152 mm) and 9 in (229 mm)wide by 75 ft(23 m)long. 2) Dryvit Flashing Tape Surface ConditionerTM: A water-based surface conditioner and adhesion promoter for the Dryvit Flashing Tape. PART III EXECUTION 3.01 EXAMINATION A. Prior to application of Backstop NT the contractor shall verify that the substrate: 1. Is of a type listed in Section 1.04.13.1. 2. Is flat within 1/4 in (6.4 mm)in a 4 ft(1.2 m) radius. 3. Gaps do not exceed 1/4 in (6.4 mm). Larger gaps shall be corrected by replacing sheathing material. 4. Is sound,dry, connections are tight; has no surface voids, projections,or other conditions that may interfere with the application of Backstop NT. 5. Is otherwise in conformance with Dryvit's Product Data Sheet, DS806 and Application Instructions, D5300. B.Ambient and surface temperatures are minimum 40 °F (4°C)to maximum 100°F(38°C). C. The contractor shall notify the general contractor and/or architect and/or owner of all discrepancies. Work shall not proceed until discrepancies have been corrected. D.All roof/wall intersections,decks, balconies and other attachments, as well as eves, chimneys, mechanical L equipment, signage etc. are properly flashed to divert water to the outside of the specified cladding. E.All openings and penetrations are properly flashed and wrapped with the air/water-resistive barrier to prevent water intrusion damage. 3.02 SURFACE PREPARATION A.The Backstop NT materials shall be protected by permanent or temporary means from inclement weather and other sources of damage prior to, during, and following application until completely dry. B. Protect adjoining work and property during application of Backstop NT. C.The substrate shall be prepared as to be free of foreign materials such as oil, efflorescence, dust, dirt, paint, wax,water repellents, moisture,frost and any other materials that inhibit adhesion. 3.03 INSTALLATION A. Backstop NT—Texture 1. General: Backstop NT—Texture shall be applied in accordance with current published Dryvit Backstop NT Application Instructions For Use Beneath Claddings Other Than Dryvit EIFS, DS300. 2. Backstop NT—Texture is ready to use after an initial spin-up using a"Twister"paddle or equivalent mixing blade, powered by a 1/2 in (12.7 mm)drill, at 450—500 rpm. Do not add cement or any other additive. 3.Apply a strip of Dryvit Grid Tape over all sheathing joints, including inside and outside corners and trowel ---apply a layer of Backstop NT-Texture over the Dryvit Grid Tape. 4. Depending on the substrate, Backstop NT—Texture may be applied using a trowel, roller, or texture spray equipment and backrolled. Refer to Backstop NT Application Instructions For Use Beneath Claddings Other Than Dryvit EIFS, D5300 for complete details. 5. Apply Backstop NT—Texture over the entire wall surface, including previously treated joints. Refer to the chart on the Backstop NT Product Data Sheet For Use Beneath Claddings Other Than Dryvit EIFS, D5806, or Application Instructions For Use Beneath Claddings Other Than Dryvit El FS, OS300,for proper tools and respective coverage. 6.Allow to dry a minimum of 4 hours prior to application of Dryvit AquaFlash or Dryvit Flashing Tape. Allow to dry a minimum of 24 hours prior to cladding installation. Cool damp weather will require longer drying L times. During cool damp weather, Flashing Tape Surface Conditioner may be necessary for proper Flashing Tape adhesion. 7. Install the specified cladding per published installation instructions for the specific cladding being used. 6