SECTION 09 24 00

CEMENT PLASTERING - STUCCO APPLICATIONS

WATERWAY RAINSCREEN STUCCO ASSEMBLY / OPTIONAL CI (CONTINUOUS INSULATION)

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PART 1    GENERAL
1.1	SECTION INCLUDES
A.	Traditional Portland Cement stucco and accessories.
B.	Insulation Material: Optional.
C.	Rainscreen drainage mat.
D.	Finish coats for stucco.
1.2	RELATED SECTIONS
A.	Section 03 30 00 - Cast-In-Place Concrete.
B.	Section 04 20 00 - Unit Masonry.
C.	Section 06 16 00 - Sheathing.
D.	Section 07 19 00 - Vapor Barriers.
E.	Section 07 50 00 - Membrane Roofing.
F.	Section 07 27 00 - Air Barrier.
G.	Section 07 62 00 - Sheet Metal Flashing and Trim.
H.	Section 07 90 00 - Sealants.
I.	Section 08 40 00 - Exterior Entrance Doors.
J.	Section 08 50 00 - Exterior Windows.
K.	Section 09 26 00 - Gypsum Board Systems.
1.3	REFERENCES
A.	ASTM International (ASTM):
1.	ASTM 641 - Standard Specification for Zinc-Coated (Galvanized) Carbon Steel Wire.
2.	ASTM C91 - Standard Specification for Masonry Cement.
3.	ASTM C150 - Standard Specification for Portland Cement.
4.	ASTM C206 - Standard Specification for Finishing Hydrated Lime.
5.	ASTM C207 - Standard Specification for Hydrated Lime for Masonry Purposes.
6.	ASTM C847 - Standard Specification for Metal Lath.
7.	ASTM C897 - Standard Specification for Aggregate for Job-Mixed Portland Cement-Based Plaster.
8.	ASTM C926 - Standard Specification for Application of Portland Cement-Based Plaster.
9.	ASTM C1063 - Standard Specification for Installation of Lathing and Furring for Portland Cement Based Plaster.
B.	Portland Cement Association (PCA):
1.	Plaster (Stucco) Manual.
C.	Plaster and Drywall Systems Manual, Third Edition.
D.	International Code Council (ICC).
E.	International Building Code (IBC).
1.4	SYSTEM DESCRIPTION
A.	Waterway Stucco Assembly: A fiber-reinforced, non-structural, plaster system comprised of a weather-resistive barrier, drainage mat, optional insulation (CI), metal lath, Portland Cement plaster base overlaid with, fiberglass reinforcing mesh, wet base coat, and an elastomeric finish coat.
B.	Waterway Stucco System: An enhanced stucco and drainage system. Intruding moisture is drained to the exterior. May be configure as back ventilated, or a dead air cavity wall cladding system with optional "Continuous Insulation".
1.	The Basic System: 
a.	Rain Screen: Protects against moisture intrusion.
b.	Drainage Cavity: Captures intruding moisture and drains it to the exterior.
c.	Permeable Air Barrier: 
1)	Protects against air infiltration into the building interior.
2)	Guards against liquid moisture intrusion.
3)	Allows for water vapor diffusion.
1.5	QUALITY ASSURANCE
A.	Manufacturer Qualifications: Company specializing in manufacturing products specified in this section with a minimum of five years documented experience.
B.	Installer Qualifications: Company specializing in performing Work of this section with minimum two years documented experience with projects of similar scope and complexity.
C.	Source Limitations: Provide each type of product from a single manufacturing source to ensure uniformity.
1.	Stuc-O-Flex Coating Products: To be obtained from Stuc-O-Flex International, Inc., as manufacturer, or its authorized supplier or distributor. Contact: 1-800-305-1045.
D.	Mock-Up: Construct a mock-up with actual materials in sufficient time for Architect's review and to not delay construction progress. Locate mock-up as acceptable to Architect and provide temporary foundations and support.
1.	The intent of a mock-up is to demonstrate quality of workmanship and visual appearance.
2.	If the mock-up is not acceptable, rebuild the mock-up until satisfactory results are achieved.
3.	Retain mock-up during construction as a standard for comparison with completed work.
4.	Do not alter or remove mock-up until work is completed or removal is authorized.
1.6	PRE-INSTALLATION CONFERENCE
A.	Convene a conference approximately two weeks before scheduled commencement of the Work. Attendees shall include Architect, Contractor and trades involved. Agenda shall include schedule, responsibilities, critical path items, and approvals.
1.7	DELIVERY, STORAGE, AND HANDLING
A.	Store and handle in strict compliance with manufacturer's written instructions and recommendations.
B.	Protect from damage due to weather, excessive temperature, and construction operations.
1.8	PROJECT CONDITIONS
A.	Maintain environmental conditions (temperature, humidity, and ventilation) within limits recommended by manufacturer for optimum results. Do not install products under environmental conditions outside manufacturer's recommended limits.
1.9	WARRANTY
A.	Manufacturer's standard limited warranty unless indicated otherwise.
PART 2    PRODUCTS
2.1	MANUFACTURERS
A.	Acceptable Manufacturer: Stuc-O-Flex, which is located at:<BR />15459 N.E. 95th St.<BR />Redmond, WA 98052<BR />Toll Free Tel: 800-305-1045<BR />Tel: 425-885-5085<BR />Fax: 425-869-0107<BR />Email: request info (techservice@stucoflex.com);Web: https://www.stucoflex.com 
B.	Substitutions: Not permitted.
C.	Requests for substitutions will be considered in accordance with the provisions of Section 01 60 00.
2.2	TRADITIONAL PORTLAND CEMENT STUCCO AND ACCESSORIES
A.	Basis of Design: Portland Cement Plaster / Stuc-O-Flex Elastomeric Acrylic Finish: A fiber-reinforced, non-structural, plaster system comprised of a weather-resistive barrier, rainscreen drainage mat, optional continuous insulation, metal lath, Portland Cement plaster base overlaid with, an optional fiberglass reinforcing mesh, an optional polymer modified base coat, and Stuc-O-Flex elastomeric acrylic finish coat.
1.	Rainscreen Drainage Mat: Upgrades system to a rainscreen back-ventilated, air cavity cladding, protecting against moisture intrusion with drainage and ventilation.
2.	Continuous Insulation creates a more energy efficient design.
B.	Fiber Reinforced Cement Stucco Materials
1.	Pre-Blended Fiber Reinforced Stucco: Factory-prepared mixture of Portland cement, aggregates and proprietary ingredients for trowel or pump application. 
a.	Field mixed with water.
2.	Traditional Cement Stucco; Scratch and Brown: 3/4 inch (19 mm) thick, compliant with local codes and requirements. 
a.	Field Mixed Stucco: Properties to meet ASTM C926 requirements for plaster thickness and base coat proportions.
b.	Synthetic Fibers: Length: 1/2 to 2 inches (13 to 51 mm). Free of contaminates and added to the stucco mixture not exceeding 2 lbs per cu ft (1.5 kg per cu m) of cementitious material.
3.	WaterWay Drainage and Ventilation Mat: A polymer core of fused, entangled filaments with a geotextile fabric bonded to one side. Used with traditional stucco and other claddings providing exterior wall drainage and ventilation. Provides a drainage path and ventilation for incidental moisture between exterior wall siding materials and weather resistive barrier.
a.	Size: WaterWay 3mm. Nominal 1/8 inch (3 mm) thick. Drainage product.
1)	A polymer core of fused entangled filaments with a moisture resistant filter fabric bonded to the outer surface. For use with manufactured and natural stone, traditional and one coat stucco, EIFS, fiber-cement and wood based sidings, masonry, metal, and other wall cladding materials. 
a)	Provides un-interrupted drainage paths and ventilation for moisture between exterior finish materials and wall sheathing.
2)	Core Material: Extruded polymer matrix.
3)	Fabric Material: Non-woven polypropylene fiber.
4)	Width: Core: 58 inches (147 cm). Filter Fabric: 62 (157 cm).
5)	Length: 3 7 ft (11.3 m).
6)	Thickness: 0.125 inch (3.2 mm).
7)	Weight: 13 lbs (5.9 kg) per roll.
8)	Footage per Roll: 180 sq ft (16.7 sq m).
b.	Size: WaterWay 7mm. Nominal 5/16 inch (7 mm) thick. Drainage product.
1)	A polymer core of fused entangled filaments with a moisture resistant filter fabric bonded to the outer surface. For use with manufactured and natural stone, traditional and one coat stucco, EIFS, fiber-cement and wood based sidings, masonry, metal, and other wall cladding materials. 
a)	Provides un-interrupted drainage paths and ventilation for moisture between exterior finish materials and wall sheathing.
2)	Core Material: Extruded polymer matrix.
3)	Fabric Material: Non-woven polypropylene fiber.
4)	Width: Core: 58 inches (147 cm). Filter Fabric: 62 (157 cm).
5)	Length: 3 7 ft (11.3 m).
6)	Thickness: 0.30 inches (7.0 mm). 
7)	Weight: 16 lbs (7.2 kg) per roll.
8)	Footage per Roll: 180 sq ft (16.7 sq m).
c.	Size: WaterWay 11mm. Vertical Wall Rainscreen. 7/16 inch (11 mm) thick.
1)	Extruded polymer matrix of tangled monofilaments heat laminated to a moisture resistant filter fabric with high perm rating on the outer side. For use with manufactured and natural stone, traditional and one coat stucco, EIFS, fiber-cement and wood based sidings, masonry, metal, and other wall cladding materials.
a)	Provides an un-interrupted drainage path and ventilation space for incidental moisture between the sheathing and exterior wall claddings. Meets Canadian Code Requirements.
2)	Core Material: Extruded polymer matrix.
3)	Fabric Material: Non-woven polypropylene fiber 
4)	Width: Core: 58 inches (147 cm). Filter Fabric: 62 (157 cm).
5)	Length: 3 7 ft (11.3 m).
6)	Thickness: 0.43 inches (11.0mm). 
7)	Weight: 25 lbs (11.36 kg) per roll. 
8)	Footage per Roll: 180 sq ft (16.7 sq m).
4.	Base Coat: Stuc-O-Base (Wet Base Coat) or Polymer Reinforced Mortar (PRM): Proprietary polymer modified cementitious base coat for embedding reinforcing mesh.
5.	Finish: Stuc-O-Flex Elastomeric Acrylic Finish: Proprietary finish coat, crack, and fade resistant. A highly resilient 100 percent acrylic polymer. Aggregate size in each finish determines the texture and coverage of each product.
a.	Stuc-O-Flex Elastomeric Finish: Fine.
b.	Stuc-O-Flex Elastomeric Finish: Sand.
c.	Stuc-O-Flex Elastomeric Finish: Modified.
d.	Stuc-O-Flex Elastomeric Finish: Putz.
C.	Accessories:
1.	Weather-Resistive Barrier: A minimum Grade "D" Kraft building paper complying with UBC Standard 14-1 (Federal Specifications UUB 790a).
2.	Weather-Resistive Barrier: Asphalt-saturated rag felt complying with UL 55-A.
3.	Weather-Resistive Barrier: Recognized in a current ICBO ES evaluation report or code compliance approval or code compliant Fluid applied weather Resistive Barriers.
4.	Insulation Board: Expanded Polystyrene (EPS). ASTM C578-85 Class A.
a.	Average Density: 1 pcf. 
b.	Flame Spread Rating: Less than 25. 
c.	Smoke Development Index: Less than 450. 
d.	R-Value: 3.85 per inch at 75 degrees F. 
5.	Insulation Board: Fiberglass faced Polyisocyanurate. ASTM C578-85 Class A.
a.	Average Density: 2.0 pcf. 
b.	Flame Spread Rating: Less than 25. 
c.	Smoke Development Index: Less than 450. 
d.	R-Value: 6.3 per inch at 75 degrees F. 
6.	Lath: No. 20 gauge 1 inch (25 mm) self-furred galvanized steel woven wire fabric in compliance with ASTM C 1032.
7.	Lath: 1.75 Ibs per sq yd (1 kg per sq m) galvanized steel diamond mesh in compliance with ASTM C 847; recommended for residential and light commercial construction.
8.	Lath: Diamond-Mesh, Expanded-Metal. Self-furring, 2.5 Ibs per sq yd (1.4 kg per sq m), in compliance with ASTM C 847, minimum G60 galvanized finish in compliance with ASTM A 653; recommended for residential and commercial construction.
9.	Heavyweight Mesh: 6.0 oz per sq yd (203 grams per sq m) fiberglass woven reinforcing mesh. Tensile Strength: 210 lbs per inch, protective coating to resist alkyl reaction with Portland Cement.
10.	Standard Mesh: 4.0 oz per sq yd (136 grams per sq m) from Stuc-O-Flex.
11.	Mechanical Fasteners:
a.	Wood or Steel Framing: 1/16 inch (1.6 mm) diameter wafer, pan-cake or modified truss head is acceptable.
b.	Concrete or Masonry: Tap Cons or Rawl Spikes used with a washer.
c.	As approved by Code.
12.	Corner mesh, vent screed, casing bead, weep screed, control, and expansion joint accessories.
a.	PVC Plastic: Compliant with ASTM D1784 and ASTM C1063.
b.	Zinc Alloy: 99.9 percent pure zinc in compliance with ASTM B69.
c.	Galvanized Metal: Compliant with ASTM A653 with minimum G60 coating. 
1)	G90 recommended for coastal applications and areas of high rainfall.
13.	Water: Clean, cool, and potable.
14.	Sand: Clean and free from deleterious amounts of loam, clay, silts, soluble salts, and organic matter. Sand Gradation: Comply with Table 1 or Table 2 per ASTM C144-97 and ASTM C897-96.
2.3	INSULATION MATERIAL (CI): 
A.	Insulation: Expanded Polystyrene (EPS) Board.
1.	Average Density: 1 pcf. 
2.	Flame Spread Rating: Less than 25. 
3.	Smoke Development Index: Less than 450. 
4.	R-Value: 3.85 per inch at 75 degrees F. 
5.	Must conform to ASTM C578-85 Class A.
B.	Insulation: Fiberglass faced Polyisocyanurate Insulation Board.
1.	Average Density: 2.0 pcf.
2.	Flame Spread Rating: Less than 25.
3.	Smoke Development Index: Less than 450.
4.	R-Value: 6.3 per inch at 75 degrees F.
5.	Must conform to ASTM C578-85 Class A.
2.4	RAINSCREEN DRAINAGE MAT - WATERWAY
A.	Rainscreen Drainage Mat with Moisture resistant filter fabric including the following: 
B.	Filter Fabric: Performance Testing:
1.	Boat Test ASTM D-779-03:
a.	H2O Vapor Transfer in 12 Minutes.
b.	96 Hours No Water Passed Through Membrane.
2.	Water Vapor Transmission Test; ASTM E-96: Perm Rating Exceeds 247.
3.	Hydrostatic Pressure Test - AATCC 127: 10 cm / 18 hours.
4.	Acceptance Criteria AC-38 / Water Resistive Barriers: 
a.	Passes section 4.2.2 Ponding Water Test.
C.	Size: WaterWay 3mm. Nominal 1/8 inch (3 mm) thick. Drainage product.
1.	A polymer core of fused entangled filaments with a moisture resistant filter fabric bonded to the outer surface. For use with manufactured and natural stone, traditional and one coat stucco, EIFS, fiber-cement and wood based sidings, masonry, metal, and other wall cladding materials. 
a.	Provides un-interrupted drainage paths and ventilation for moisture between exterior finish materials and wall sheathing.
2.	Core Material: Extruded polymer matrix.
3.	Fabric Material: Non-woven polypropylene fiber.
4.	Width: Core: 58 inches (147 cm). Filter Fabric: 62 (157 cm).
5.	Length: 37 ft (11.3 m). 
6.	Thickness: 0.125 inch (3.2 mm).
7.	Weight: 13 lbs per roll. (5.9 kg per roll).
8.	Footage per Roll: 180 sq ft (16.7 sq m).
D.	Size: WaterWay 7mm. Nominal 5/16 inch (7 mm) thick. Drainage product.
1.	A polymer core of fused entangled filaments with a moisture resistant filter fabric bonded to the outer surface. For use with manufactured and natural stone, traditional and one coat stucco, EIFS, fiber-cement and wood based sidings, masonry, metal, and other wall cladding materials.
a.	Provides un-interrupted drainage paths and ventilation for moisture between exterior finish materials and wall sheathing.
2.	Core Material: Extruded Polymer Matrix. 
3.	Fabric Material: Non-woven polypropylene fiber.
4.	Width: Core: 58 inches (147 cm). Filter Fabric: 62 (157 cm).
5.	Length: 37 ft (11.3 m).
6.	Thickness: 0.30 inches (7.0 mm).
7.	Weight: 16 lb. per roll. 7.2 kg per roll.
8.	Footage per Roll: 180 sq. ft. per 16.7 sq. m.
E.	Size: WaterWay 11mm. Vertical Wall Rainscreen. 7/16 inch (11 mm) thick. 
1.	Extruded polymer matrix of tangled monofilaments heat laminated to a moisture resistant filter fabric with high perm rating on the outer side. For use with manufactured and natural stone, traditional and one coat stucco, EIFS, fiber-cement and wood based sidings, masonry, metal, and other wall cladding materials.
a.	Provides an un-interrupted drainage path and ventilation space for incidental moisture between the sheathing and exterior wall claddings. Meets Canadian Code Requirements.
2.	Core Material: Extruded polymer matrix.
3.	Fabric Material: Non-woven polypropylene fiber.
4.	Width: Core: 58 inches (147 cm). Filter Fabric: 62 (157 cm).
5.	Length: 37 ft (11.3 m).
6.	Thickness: 0.43 inches (11.0mm).
7.	Weight: 25 lbs (11.36 kg) per roll.
8.	Footage per Roll: 180 sq ft (16.7 sq m).
F.	Accessories: Provide the following.
1.	Housewrap / Air barrier:
a.	Material: ________ 
b.	Manufacturer: ________.
2.	Building Paper:
a.	Material: ________ 
b.	Manufacturer: ________.
3.	Fasteners:
a.	Type: Galvanized Roofing Nails.
b.	Type: Plastic Cap Nails.
c.	Type: Staples.
d.	Material: Corrosion protected steel.
e.	Material Standard: ________.
f.	Manufacturer: ________.
g.	Size: Suitable for project application.
2.5	FINISH COATS FOR STUCCO
A.	Basis of Design: Stuc-O-Flex Elastomeric Acrylic finish properly prepared and applied to cement stucco / concrete substrates.
1.	Performance and Design Requirements:
a.	Products required, excluding cement stucco / concrete, are to be obtained from Stuc-O-Flex International or an authorized Distributor, unless otherwise approved in writing.
b.	Finish: Meet standards as outlined below.
1)	Contain only calcium aggregates without silica sand.
2)	Comprised of only 100 percent acrylic polymer binders.
3)	Exceed 105 percent elongation.
4)	Have in excess of 450 million sq ft in service.
5)	Exceed a 1/8 inch (3 mm) mandrel bend test without rupture of the membrane.
c.	Stuc-O-Flex Coatings Comply with Following Test Standards: 
1)	Elongation, percent (finish). Method: ASTM E96. 
a)	Result: 105 Percent.
2)	Water Vapor Transmission. Method: ASTM-E96. 
a)	Result: 13 Grains per hour per sq ft; average.
3)	Salt Spray Resistance. Method: ASTM B117. 
a)	Result: 300 hours. No deleterious effect.
4)	Accelerated Weathering. Method: ASTM G23-81.
a)	Result: 2000 hours. No deleterious effects.
5)	Absorption Freeze Thaw. Method: 60 cycles.
a)	Result: No Cracking, checking.
6)	Tensile Bond. Method: ASTM C-297.
a)	Result: 97.9 psi.
7)	Water Penetration Test: ASTM-E331.
a)	Result: No Water Penetration Occurred on Substrate.
8)	Water Resistance Test. Method: ASTM D-2247.
a)	Result: No Cracking, Blistering, Peeling or Compromise.
9)	Mildew / Fungus Resistance. Method: 810 B.
a)	Result: No Mold or Mildew Growth During Test.
10)	Wind Driven Rain. Method: N/A. 
a)	Result: No Delamination. No water intrusion.
11)	Fire Testing Tunnel. Method: ASTM E-84. 
a)	Result: Flame spread to less than 25.
b)	Result: Smoke developed to be less than 450.
c)	Result: Class "A" Fire rated.
d.	Cement / Stucco / Concrete Substrates:
1)	Moisture Content of Stucco / Concrete: 19 percent maximum at time of Stuc-O-Flex application.
2)	Stucco / Concrete Base: Fully cured, clean, dry, and free of all form-break, efflorescence, and foreign materials.
3)	Portland Cement Plaster / Stucco / Concrete: Installed as required by applicable building codes. For "one-coat" stucco, manufacturer's specifications are to be followed.
4)	System Interface with Adjacent Materials and/or Terminations: Does not allow moisture behind the stucco system, concrete, or Stuc-O-Flex Finish.
e.	Minimum Slope, any Surface: 4 in 12 inches (102 to 305 mm).
f.	To ensure long term performance, the stucco / concrete system shall be engineered with regard for intended installation.
g.	Expansion Joint Details: Required as specified by the design professional in addition to; where dissimilar materials abut, in conjunction with building expansion joints, not exceeding 144 sq ft of wall surface, and where extreme structural movement may occur.
h.	Acrylic Based Stain Blocking Primer: Prime Seal. Protects substrate from moisture, provides for uniform porosity, and prevents any potential bleed through which could discolor finish coat.
i.	Stuc-O-Flex, Elastomeric Acrylic Finish: Factory premixed, acrylic based, color integrated, textured finish for use with this application. Numerous textures can be achieved using a variety of application methods. Spray application or by hawk trowel; sand finish, skip trowel, knock down, lace, etc. 
1)	Color: ________.
j.	Water: Clean and potable in clean containers without any residue or foreign materials. 
k.	Caulking: Sealant system of appropriate quality to prevent water intrusion. Consult construction documents and manufacturer for specific recommendations and details.
2.	Mixing and Preparation:
a.	Prime Seal: Mix to a uniform consistency (do not add water).
b.	Stuc-O-Flex Elastomeric Acrylic Finish:
1)	Mix with paddle type mixer and 1/2 inch (13 mm) drill to assure consistency prior to use. Small amounts of clean water can be added to the Stuc-O-Flex Elastomeric Acrylic Finish to aid workability. Spraying the finish requires thinning with water, 12 to 20 oz. of water per pail. Use caution not to introduce air into the finish.
c.	Never add modifiers, admixtures, or other products to any Stuc-O-Flex product.
PART 3    EXECUTION
3.1	MANUFACTURER'S INSTRUCTIONS
A.	Comply with Manufacturer's instructions and recommendations.
3.2	EXAMINATION
A.	Verify Site Conditions are Acceptable:
1.	Do not begin installation until substrates have been properly prepared.
2.	Acceptable Sheathing Types: Consult local building codes for approved materials.
a.	Sheathing Typically Approved for Local Use: Plywood, oriented strand board, water-resistant gypsum, and others.
B.	Inspect Surfaces Prior to Stucco Application: 
1.	Confirm contaminants are not present.
a.	Contaminates: Algae, chalkiness, dirt, dust, efflorescence, form oil, fungus, grease, laitance, mildew, or other foreign substances.
2.	Surface absorption and chalkiness.
3.	Cracks have been repaired.
4.	Damage, deterioration, and moisture to the substrate is not present.
5.	Verify concrete surfaces receiving stucco are prepared to provide adequate bond.
6.	Receiving Substrate: 
a.	Must be dry, sound, and free of release agents (silicones, oils, etc.), paint and other residue or coatings.
b.	No planar irregularities greater than 1/4 inch (6 mm) in 8 feet (2438 mm).
C.	If substrate preparation is the responsibility of another installer, notify Architect of unsatisfactory preparation before proceeding.
3.3	PREPARATION
A.	Clean surfaces thoroughly prior to installation.
B.	Prepare surfaces using methods recommended by the Manufacturer for achieving the best result under the project conditions.
C.	Concrete (Cast-in-Place) Surface: Slightly scarified, water absorbent, straight and true to line and plane. 
1.	Remove:
a.	Form ties and trim projecting concrete so it is even with the wall plane. 
b.	Form release agents by washing with a trisodium phosphate detergent and rinsing with clean water. 
2.	Surface Profile: Establish by abrasive blasting, water-blasting, wire brushing, chipping, or other appropriate means. 
a.	Remove: Dust, dirt, grease, laitance, or other bond inhibiting material. 
3.	Absorbent Material Surfaces: Pre-moisten with water prior to stucco placement.
D.	Concrete Masonry Units: 
1.	Projecting joint mortar so it is even with the wall plane. 
2.	Remove Surface Contaminants: Efflorescence, existing paint, or other bond inhibiting materials. 
a.	Methodology: Sandblasting, water blasting, wire brushing, chipping, or other appropriate means acceptable to the Manufacturer. 
3.	Surface Preparation: Pre-moisten with water just prior to stucco placement or apply one uniform coat of bonding agent by brush or roller.
E.	Gypsum Sheathing: Comply with ASTM C79, Glass Mat Faced Gypsum Sheathing in compliance with ASTM C 1177, and Exterior or Exposure 1 wood based sheathing; plywood and OSB Oriented Strand Board:
1.	Verify sheathing installation is in compliance with applicable requirements.
2.	Wood Based Sheathing To be installed with 1/8 inch (3 mm) spacing at edge and end joints.
3.	Substrate Protection: A weather-resistive barrier as required by the applicable code and install lath and accessories.
F.	Metal Flashing Installation: Per Specification Section 07 60 00 Flashing and Sheet Metal.
3.4	MIXING
A.	Mixing the Scratch and Brown or Factory Pre-blend Stucco:
1.	Typical Mixing Materials:
a.	Portland Cement: One, 80 lbs (36 kg) bag.
b.	Scratch Coat Sand: 180 to 220 lbs (82 - 100 kg).
c.	Brown Coat Sand: 180 to 200 lbs (82 - 100 kg).
2.	Mixing Procedure:
a.	For Consistent Results: 
1)	Use a mechanical mixer.
2)	Measure the sand and water.
b.	Add two-thirds to three-fourths of the required water to mixer. 
1)	Adjust water amount based on experience and required workability.
c.	Add half of the required sand.
d.	Add measured amounts of Portland cement.
e.	Add remaining sand.
f.	Mix until a uniform lump free texture is observed.
g.	Add additional water to achieve desired workability.
h.	Machine Mixing: 
1)	Mixing Time: 4 to 5 minutes to obtain maximum workability. 
a)	4 minutes improves workability and water retention for hand application. 
b)	Not Recommended: Mixing over 5 minutes.
1)	Over Mixing: Will entrain excess air, which will lower the compressive strength.
B.	Mixing Stuc-O-Base (Wet Base Coat):
1.	Should be mixed 1:1 by weight with fresh, dry Portland Cement type I or II. 
2.	Allow product to sit for 10 minutes. Then remix to be ready for use.
C.	Mixing Polymer Reinforced Mortar (PRM):
1.	Should be mixed with approximately 2.5 gallons of clean, cold water. 
2.	Allow product s to sit for 10 minutes. Then remix to a uniform consistency.
D.	Mixing Stuc-O-Flex Elastomeric Acrylic Finish:
1.	Use a paddle type mixer and 1/2 inch (13 mm) drill to assure consistency prior to use. 
a.	Small amounts of Clean Water: Can be added to aid workability. 
b.	Spray Applied: Requires thinning with 12 to 24 oz of water per pail.
2.	Finish: Varies greatly depending on desired texture. 
a.	Usually, the finish is trowel applied and textured with plastic floats while wet. 
b.	Spray Finish: Requires proper equipment. 
1)	Refer to Manufacturer's spray application instructions.
3.5	INSTALLATION
A.	Coordinate Corrosion Resistant Flashing Installation: Direct water to the exterior where it is likely to penetrate components in the wall assembly, including but not limited to:
1.	Above window and door heads.
2.	Beneath window and door sills.
3.	At roof and wall intersections.
4.	Decks.
5.	Abutments of lower walls with higher walls.
6.	Above projecting features.
7.	At Wall bases.
B.	Trim and Projecting Architectural Features: 
1.	Minimum Slope Along Top Surface: 1:2 (27 degree)
a.	Increase slope in northern climates to prevent ice, snow, and water accumulation on the surface. Refer to local codes having jurisdiction.
2.	Where Trim, Feature or Reveal Bottom Projects more than 2 inches (51 mm) from the Wall Plane Face:
a.	Protect upward facing surface with waterproofing. 
3.	Weather Exposed Sloped Surfaces: May require periodic inspections and increased maintenance to maintain the finish surface integrity. 
4.	Limit projecting features to easily accessible areas and limit total area to facilitate maintenance and minimize maintenance burden.
C.	Installation over Frame Construction with Sheathing:
1.	Sheathing:
a.	Surface Plane Tolerance: Not to exceed 1/4 inch in 10 feet (6 mm in 3 m). Repair defects, leveling, or resurface areas not meeting required tolerances.
b.	Gypsum Attachment: With fasteners spaced 6 inches (152 mm) on center in the field and 6 inches (15 cm) along the perimeter.
2.	Plywood: Comply with UBC Standard 23-2 (US DOC PS1-95).
a.	Thickness: Minimum 5/16 inch (8 mm) thickness with exterior glue.
1)	Stud Spacing: A maximum of 16 inches (406 mm) on center. 
b.	Thickness: Minimum 3/8 inch (9.5 mm) thickness with exterior glue.
1)	Stud Spacing: A maximum of 24 inches (610 mm) on center.
c.	Install in accordance with governing codes.
d.	Comply with American Plywood Association recommendations requiring 1/8 inch (3 mm) spacing between sheets at ends and sides.
3.	Oriented Strand Board (OSB):
a.	Comply with specifications for Exposure 1, performance rated panels in UBC Standard 23-3 (US DOC PS2-92).
1)	Minimum Thickness: 3/8 inch (9.5 mm). 
b.	Install in accordance with governing codes.
c.	Comply with American Plywood Association recommendations requiring 1/8 inch (3 mm) spacing between sheets at ends and sides.
4.	Foundation Weep Screed Installation:
a.	Install at the wall base. Secure to framing with appropriate fasteners. 
b.	Joints Between the Foundation and Framing: Overlap by a minimum of 1 inch (25 mm). 
c.	At Earth Grade: Locate a minimum 4 inches (101 mm) above.
d.	At Finish Grade: Locate 2 inches (51 mm) above.
5.	Weather-Resistive Barrier: Install two layers over substrate.
a.	Material: Asphalt-saturated Kraft 60 minute Grade "D" breather type sheathing paper
b.	At Horizontal Terminations: Lap 3 inches (76 mm) minimum.
c.	At Vertical Terminations: Lap 6 inches (152 mm) minimum.
d.	Extend barrier over flanges at window heads and jambs. 
1)	Extend under sill flange.
e.	Self-Adhered, Flexible Membrane Flashing: Use on transitions where a 6 inch (152 mm) horizontal lap or 9 inch (229 mm) vertical lap cannot be achieved between the weather-resistive barrier and adjoining flashing leg or nailing flange.
f.	Cuts Required to be Made in the Barrier: Must be weather lapped with additional barrier material.
g.	Verify:
1)	Terminations at windows, doors, and other openings are properly lapped and flashed.
2)	Barrier is properly weather lapped, flashed and integrated at window, door, and louver openings.
6.	Waterway Rainscreen and Ventilation Mat Profile No. __________:
a.	Refer to "Installation Guide for Flashing Windows/Doors".
b.	Ensure weather-resistive barrier is properly installed to allow proper detailing and installation of Waterway Drainage Mat.
c.	Horizontal Applications: Work from bottom to top 
d.	Vertical Applications: Work from a corner. 
e.	Wrap building completely, stopping at wall ends. 
1)	Ends: Terminate at a furring strip of matching thickness to prevent air movement to adjoining wall. 
2)	Butt edges of the Waterway mat together. Do not overlap.
f.	Window and Door Openings: Install WaterWay tightly to casings. 
1)	Do not cut or damage weather-resistive barrier.
g.	At Mat Bottom: Place a foundation weep screed, a "J" weep screed, or flashing with weeps. 
h.	Weather-Resistive Barrier and Mat: Place over top of the back piece of the weep screed, termination bar, or flashing to create the proper weather lap.
i.	At Wall Terminations: Place a wood termination strip along the outside edge of each wall to create a wind dam for negative wind load.
j.	Maximum Exposure of WaterWay Rainscreen: Not to exceed 60 days, prior to cladding installation.
7.	Insulation Board (CI) Continuos Insulation :
a.	Install per manufacturers installation instructions. 
1)	Use appropriate compression disk to secure the insulation board through the rainscreen and substrate to the structural framework.
b.	Make sure the correct fastener type is used for the framing and substrate type and the recommended installation pattern is followed
8.	The purposes of the typical accessories are as follows:
a.	Corner Joints: At internal angles.
b.	Control Joints: At stress concentrations in plaster.
1)	Install in walls to produce panels of no more than 144 sq ft (13 sq m) in area and a length to width ratio not exceeding 2.5 to 1.0 for any panel. Spacing: No further apart than 18 ft. (5.5 m); ASTM C1063 and ACI, Section 7.3.
c.	Expansion Joint: At discontinuities in the substrate and at every floor line. 
1)	Lath shall be discontinuous behind the expansion joint. 
2)	Weather-Resistive Barrier, Waterway Profile No. _______, and Lath: Are to lap over the top flange of the horizontal expansion joint. 
3)	All horizontal expansion joints are to weep.
9.	Metal Lath: Diamond Mesh Self Furring Expanded Metal
a.	Applied with long sheet dimensions perpendicular to framing/supports. Fasteners for Attaching Lath to Solid Substrates; Plywood or OSB: Not less than 1-1/4 inch (32 mm) long.
1)	Minimum Driven Penetration: 3/4 inch (19 mm); ASTM C1063, Section 7.10.2.
2)	Fasten securely through sheathing into structural framing at 7 inches (178 mm) on center maximum vertically and 16 inches (41 cm) on center horizontally. 
b.	Wire Tie: At no more than 9 inches (229 mm) on center at side laps, accessory overlaps, and where end laps occur between supports.
c.	Lap Lath 1/2 inch (13 mm) at the sides and 1 inch (25 mm) at the ends; ACI 524, Section 8.2.
10.	Stucco Installation:
a.	Scratch Coat (First Coat): Apply with sufficient pressure to key into and embed the metal lath. 
1)	Apply material, approximately 3/8 inch (9mm) thick, to cover the metal lath and permit scoring the surface. 
2)	Score stucco horizontally upon completion of each panel in preparation for a second coat. 
b.	Brown Coat (Second Coat): Apply as soon as the first coat is firm enough to receive the second coat without damage.
1)	Apply sufficient pressure to ensure intimate contact with the first coat to a uniform thickness of 1/8 to 3/8 inch (3 to 9 mm) matching the grounds of the 3/4 inch (19 mm) accessories. 
2)	Use a rod or straight edge to bring the surface to a true, even plane. 
3)	Fill depressions in plane with stucco.
c.	Provide curing conditions as required by the manufacturer and building code requirements for traditional stucco.
11.	Wet Base Coat and Mesh Installation (Stuc-O-Base or PRM):
a.	Apply in Two Layers as Follows:
1)	First Layer: Apply to brown coat surface at least 50 mils (1.3 mm) thick.
2)	Fiberglass Woven Reinforcing Mesh: Apply to the base material surface.
a)	Trowel from the center to the edge of the mesh to avoid wrinkles. 
b)	Mesh: To be continuous 8 inches (203 mm) around corners and doubled at inside corners. 
1)	Lap Mesh: 2-1/2 inches (64 mm) minimum at mesh joints.
2)	Offset mesh joints 6 inches (152 mm) from corner mesh joints.
3)	Mesh Laps: Must not align with corners of window, door, and similar wall openings. 
4)	Once attached, mesh color is not to be visible.
a)	Mesh Pattern: Should be visible but not tactile.
b)	Do not fully embedded in the first base layer. 
c)	Do not remove material while troweling mesh. 
5)	Mesh is not to be in contact with the brown coat nor protrude from the surface of the base coat.
3)	Second Layer: Apply s at least 30 mils (0.8 mm) thick.
4)	Completed Base Coat: 
a)	Thickness: 80 to 90 mils (2.0 to 2.3 mm). 
1)	Do not exceed 90 mils (2.3 mm) thickness.
2)	Mesh Pattern and Color: To be no longer visible. 
a)	If the mesh pattern, or mesh ends are visible, apply additional base material.
b)	Trowel inside and outside comers with comer trowels.
c)	Trowel aesthetic grooves with groove trowels. 
d)	Do not use wet brushes to smooth comers or grooves. 
e)	Dry brushes may be used if needed.
12.	Stuc-O-Flex Elastomeric Acrylic Finish Installation:
a.	Substrate Inspection:
1)	Stucco / Concrete Assembly: Examine for compliance with construction documents and system specifications prior to installation. 
a)	To be installed in accordance with manufacturer's recommendations and applicable building codes providing a smooth, dry substrate on which to accept the finish.
b)	Appropriate Curing Times: For a structurally sound substrate with a moisture content of 19 percent or less.
2)	Allowable Planar Irregularity: 1/4 inch in 8 ft maximum in any direction.
3)	Architect and General Contractor: Must be made aware of any substrate concerns. 
a)	Problem Areas: Rectify before installation continues.
4)	Details for proper sealant joints are to be required.
5)	Pre-Based EPS Foam Shapes: If used, install at this time to ensure trim details are fully embedded in base coat and fiberglass reinforcing mesh, providing a structurally sound, aesthetically pleasing detail.. 
a)	Adhesive Attachment: Coat the back of the shapes with Stuc-O-Base or Polymer Reinforced Mortar (PRM) basecoat. 
1)	Using manufacturer supplied fiberglass mesh and base coat, the shapes must be feathered into the adjacent wall area. Leave a minimum 6 inches of mesh on both the shape and the wall surface.
b)	Allow base coat to dry 24 hours minimum or until dried below 19 percent moisture content. 
6)	Primeseal: Apply primer with airless sprayer, medium nap roller, or paint brush to areas which Stuc-O-Flex Finish coat is to be applied. 
a)	A uniform pinhole free layer should be provided to ensure no shadowing or discoloration will occur from the Stucco / concrete substrate underneath.
b)	Backrolling while wet is recommended for spray applications. 
c)	Allow primer to dry completely.
b.	Finish Installation:
1)	Mask areas not to receive finish, including areas to receive sealant, adjacent materials, and abutting areas of different color or texture finish, to provide straight, clean lines.
2)	Mix Finish Thoroughly: Use a low speed, rust free mixer until a workable consistency is obtained. 
a)	Small amounts of clean water may be added to aid workability. 
1)	If Water is Added: Measure and add the same amount to all pails of finish to ensure uniform color.
3)	Finish Application
a)	Apply thoroughly clean, cured, and dry basecoat / stucco.
b)	Apply with uniform texture. 
c)	Use sufficient number of applicators so a wet edge is maintained. 
d)	Work continuously to prevent cold joints. Stop work only at joints, color changes, or inside/outside corners.
e)	Avoid application in direct sunlight.
4)	Final Appearance: Match approved samples to the Architect's /Owner's satisfaction.
5)	Do not use finish on horizontal or near horizontal weather-exposed surfaces, such as tops of parapets, projecting ledges, sills, or other projecting features. 
a)	Protect such surfaces with metal coping or flashing with drip edge.
6)	Prevent application of finish over isolation, expansion, cold, or control joints in construction.
7)	Prevent application of finish along inside edges of joint. Apply to outside face of wall only.
3.6	PROTECTION
A.	Installed Materials: Protect from water infiltration into or behind them.
B.	Installed Stucco: Protect from dust, dirt, precipitation, and freezing during installation.
C.	Installed Finish: Protect from dust, dirt, precipitation, freezing and continuous high humidity until fully cured and dry.
D.	Exposed Surfaces: Clean using materials and methods recommended by the Manufacturer for the material or product being cleaned. 
E.	Remove and replace work that cannot be cleaned to the satisfaction of the Architect/Owner.
F.	Secure fixtures, signs, and similar items, and make watertight.
3.7	JOB SITE CLEAN UP
A.	Stuc-O-Flex Applicator: Remove excess wall system materials from completed project areas.
B.	Remove coverings, scaffolds, etc. 

END OF SECTION