RFI__50_-084413.pdf

10-01-15

512-173 08 44 13 - 1

SECTION 08 44 13

GLAZED ALUMINUM CURTAIN WALLS

PART 1 - GENERAL

1.1 DESCRIPTION:

A. This section specifies glazed aluminum curtain wall system.

1. Thermally isolated, pressure equalized on interior.

2. Type: Stick system to include following:

a. Glass Glass Spandrel Panels.

b. Integral reinforcing.

c. Closures, trim, subsills and flashings.

d. Column covers.

e. Fasteners, anchors, and related reinforcement.

1.2 RELATED WORK:

A. Sustainable Design Requirements: Section 01 81 11, SUSTAINABLE

CONSTRUCTION REQUIREMENTS.

B. Structural Steel: Section 05 12 00, STRUCTURAL STEEL FRAMING.

C. Miscellaneous Metal Members: Section 05 50 00, METAL FABRICATIONS.

D. Firestopping between Curtain Wall and Structure: Section 07 84 00, FIRESTOPPING.

1. Sheet Metal Flashing and Trim: Section 07 60 00, FLASHING AND SHEET

METAL.

E. Joint Sealants: Section 07 92 00, JOINT SEALANTS.

F. Aluminum and Glass Hinged Entry Doors and Storefront Construction:

Section 08 41 13, ALUMINUM-FRAMED ENTRANCES AND STOREFRONTS.

G. Aluminum Windows: Section 08 51 13, ALUMINUM WINDOWS.

H. Glazing: Section 08 80 00, GLAZING.

I. Finish Color: Section 09 06 00, SCHEDULE FOR FINISHES.

J. Louvers and Wall Vents: Section 08 90 00, LOUVERS AND VENTS.

1.3 QUALITY ASSURANCE:

A. Qualifications:

1. Approval by Resident Engineer is required of products or service of proposed manufacturer, suppliers and installers, and will be based upon submission by Contractor of certification that:

a. Manufacturers Qualifications: Manufacturer with five (5) years continuous documented experience in design, fabrication, and installation of glazed aluminum curtain wall systems of similar type and for projects of equivalent size.

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b. Installer: Manufacturer approved in writing who has continuously installed glazed aluminum curtain walls systems of similar type and for projects of equivalent size for previous five (5) years.

c. Manufacturer is to provide technical field representation at project site, as a minimum, at start of project, during middle, towards end of project, and during field testing of field mockup panel.

d. Manufacturers Professional Engineer Qualifications: A

Professional Engineer who is legally qualified to practice in state where Project is located and who is experienced in providing engineering services of kind indicated. Engineering services are defined as those performed for installations of glazed aluminum curtain walls that are similar to those indicated for this Project in material, design, and extent.

e. Testing Laboratory: Contractor is to retain AAMA accredited commercial testing laboratory to perform tests specified. Submit information regarding testing laboratory’s facilities and qualifications of technical personnel to perform testing specified in this section.

f. Product Options: Information on construction documents establishes requirements for aesthetic effects and performance characteristics of glazed aluminum curtain wall system.

Aesthetic effects are indicated by dimensions, arrangements, alignment, and profiles of components and assemblies as they relate to sightlines, one another, and adjoining construction.

Performance characteristics are indicated by criteria subject to verification by one (1) or more methods including preconstruction testing, field testing, or in-service performance.

1) Do not modify intended aesthetic effects. If modifications are proposed, submit comprehensive explanatory data for review.

g. Qualification of Welders:

1) Welding is to be performed by certified welders qualified in accordance with AWS D1.2/D1.2M, using procedures, materials, and equipment of the type required for this work.

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B. Pre-Installation Conference

1. Prior to starting installation of glazed curtain wall system schedule conference with Resident Engineer to demonstrate the following:

a. Clear understanding of construction documents.

b. Onsite inspection and acceptance of structural and pertinent structural details relating to curtain wall system.

c. Coordination of work of various trades involved. Conference is to be attended by Contractor; personnel directly responsible for installation of curtain wall system, flashing and sheet metal work, firestopping system and curtain wall manufacturer and their technical field representatives. Conflicts are to be resolved and confirmed in writing.

1.4 SUBMITTALS:

A. In accordance with Section 01 33 23, SHOP DRAWINGS, PRODUCT DATA, AND

SAMPLES.

B. Sustainable Design Submittals, as described below:

1. Volatile organic compounds per volume as specified in

PART 2 - PRODUCTS.

C. Manufacturer's Literature and Product Data:

1. Manufacturer’s standard details and fabrication methods.

2. Data on finishing, components, and accessories.

3. Instructions: Submit descriptive literature, detail specifications, performance test data and instructions for installation, and adjustments.

4. Recommendations for maintenance and cleaning of exterior surfaces.

D. Shop Drawings:

1. Show elevations of glazed curtain wall system at 1:48 (1/4 inch) scale, metal gages, details of construction, methods of anchorage, flashing and coping details, glazing details, firestopping assemblies at edge of slabs and details of installation. Show interfaces and relationships to work of other trades and continuity with adjacent thermal, weather, air and vapor barriers.

2. Submit for curtain wall system, accessories. Tentative approval of drawings is to be received before fabrication of mock-up. Final approval of drawings is to be deferred pending approval of mock-up and accessories.

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3. Operation and Maintenance Manuals

a. Submit cleaning and maintenance instructions.

E. Samples:

1. Submit pairs of samples of each specified color and finish on

305 mm (12-inch) long section by width of each tubular, or extruded shape section or 305 mm by 305 mm (12-inch by 12-inch) wide sections of sheet shapes.

2. Submit corner section of framing members showing fasteners, panels, glazing methods, glazing materials, and weather-stripping. Submit one (1) sample minimum 305 mm by 305 mm (12 inches by 12 inches).

In lieu of submitting separate samples for corner section, intermediate section, and panel, one (1) composite sample incorporating all components and features listed may be submitted.

3. Where normal color variations are anticipated, include two (2) or more units of each sample indicating extreme limits of color variations.

F. Glass:

1. Specified in Section 08 80 00, GLAZING.

G. Blast Mitigation Reports: Submit blast mitigation reports that include a summary narrative, structural design sketches, and structural design calculations, for the work required to resist blast loads for the glazed aluminum curtain walls, showing compliance with blast performance requirements. Blast reports shall be prepared and submitted by qualified blast engineering consultants who are experienced in blast resistant design of these systems.

H. Quality Assurance Submittals:

1. Design Data:

a. Submit structural and thermal calculations for complete wall assembly. Structural calculations and design shop drawings signed and sealed by a Professional Engineer (PE).

2. Factory Test Reports:

a. Test Reports: Submit certified test reports, for each of following listed tests, from a qualified independent testing laboratory showing that glazed aluminum curtain wall system assembly has been tested in accordance with specified test procedures and complies with performance characteristics as indicated by manufacturer’s testing procedures. Submit factory

08 44 13 - 5 tests required except that where a curtain wall system or component of similar type, size, and design as specified for this project has been previously tested within last year, under conditions specified herein, resulting test reports may be submitted in lieu of listed testing. Submit appropriate testing reports for specific tests indicated below:

1) Deflection and structural tests.

2) Water penetration tests.

3) Air infiltration tests.

4) Delamination tests.

5) Thermal conductance tests.

I. Manufacturer's Certificates:

1. Submit Certificates of Compliance, with specification requirements, for the following:

a. Metal extrusions.

b. Metal accessories.

c. Statement(s) that aluminum has been given specified thickness of anodizing or organic coating finish.

d. Statement(s) indicating manufacturers and installers conform with qualifications as specified.

e. Submit list (minimum of five (5)) of equivalent project size installations for both manufacturer and installer.

J. Manufacturer’s Field Reports:

1. Submit field reports of manufacturer’s field representative observations of curtain wall installation indicating observations made during inspection at beginning of project, during middle of installation and at conclusion of project.

K. Welders: Submit welders qualifications as specified.

L. Testing Laboratory: Submit Testing Laboratory qualifications.

1.5 DELIVERY, STORAGE AND HANDLING:

A. Refer to AAMA CW 10 for care and handling of architectural aluminum from shop to site.

B. Prior to packaging for shipment from factory, mark wall components to correspond with shop and erection drawings and their placement location and erection sequence.

C. Prior to shipment from factory, place knocked-down lineal curtain wall members in cardboard containers and cover finished surfaces of members with protective covering of adhesive paper, waterproof tape, or

08 44 13 - 6 strippable plastic. Do not cover metal surfaces that will be in contact with sealants after installation.

D. Inspect materials delivered to site for damage; unload and store with ventilation, free from heavy dust, not subject to combustion products or sources of water, and to permit easy access for inspection and handling. Sealing and caulking compounds, including handling, is to be in accordance with requirements of Section 07 92 00, JOINT SEALANTS.

1.6 PROJECT CONDITIONS:

A. Field Measurements: Where glazed aluminum curtain wall systems are indicated to fit to other construction, verify dimensions of other construction by field measurements before fabrication and indicate measurements on shop drawings. Coordinate fabrication schedule with construction progress to avoid delaying Work.

1.7 APPLICABLE PUBLICATIONS:

A. Publications listed below form a part of this specification to extent referenced. Publications are referred to in text by basic designation only.

B. American Architectural Manufacturers Association (AAMA):

501.8-13 ...............Test Method for Determination of Resistance of

Human Impact of Window Systems Intended for Use in Psychiatric Applications

MCWM-1-89 ..............Metal Curtain Wall Manual

CW 10-12 ...............Care and Handling of Architectural Aluminum from Shop to Site

CW 11-85 ...............Design Windloads for Buildings and Boundary

Layer Wind Tunnel Testing

CW 13-85 ...............Structural Sealant Glazing Systems (A Design

Guide)

TIR A11-04 .............Maximum Allowable Deflection of Framing Systems for Building Cladding Components of Design Wind

Loads

501-05 .................Methods of Test for Exterior Walls

503-08 .................Field Testing of Metal Storefronts, Curtain walls and Sloped Glazing Systems

2605-13 ................High Performance Organic Coatings on

Architectural Extrusions and Panels

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C. American Society of Civil Engineers (ASCE):

ASCE 7-10 ..............Minimum Design Loads for Buildings and Other

Structures

D. ASTM International (ASTM):

A36/A36M-12 ............Structural Steel

A123/A123M-13 ..........Zinc (Hot-Dip Galvanized) Coatings on Iron and

Steel Products

A193/A193M-14a .........Alloy-Steel and Stainless Steel Bolting

Materials for High Temperature Service

A307-14 ................Carbon Steel Bolts and Studs, 60,000 PSI

Tensile Strength

B209-14 ................Aluminum and Aluminum Alloy Sheet and Plate

B209M-14 ...............Aluminum and Aluminum Alloy Sheet and Plate

(Metric)

B211-12 ................Aluminum and Aluminum Alloy Bar, Rod, Wire

B211M-12 ...............Aluminum and Aluminum Alloy Bar, Rod, Wire

(Metric)

B221-14 ................Aluminum and Aluminum Alloy Extruded Bars, Rods, Wire, Shapes and Tubes

B221M-13 ...............Aluminum and Aluminum Alloy Extruded Bars, Rods, Wire, Shapes and Tubes (Metric)

B316/B316M-10 ..........Aluminum and Aluminum Alloy Rivet and Cold-

Heading, Wire, and Rods

C578-14a ...............Rigid Cellular Polystyrene Thermal Insulation

C612-14 ................Mineral Fiber Block and Board Thermal

Insulation

C920-14a ...............Elastomeric Joint Sealants

C794-10 ................Standard Test Method for Adhesion-In-Peel of

Elastomeric Joint Sealants.

C1193-13 ...............Guide for Use of Joint Sealants

C1363-11 ...............Thermal Performance of Building Materials and

Envelope Assemblies by Means of a Hot Box

Apparatus

C1521-13 ...............Practice for Evaluating Adhesion of Installed

Weatherproofing

D1037-12 ...............Evaluating the Properties of Wood-Base Fibers and Particle Panel Materials

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E84-14 .................Surface Burning Characteristics of Building

Materials

E330/E330M-14 ..........Structural Performance of Exterior Windows, Curtain Walls, and Doors by Uniform Static Air

Pressure Difference

E331-00(R2009) .........Water Penetration of Exterior Windows, Curtain

Walls, and Doors By Uniform Static Air Pressure

Difference

E413-10 ................Classification for Rating Sound Insulation

E783-02(R2010) .........Test Method for Field Measurement of Air

Leakage Through Installed Exterior Windows and

Doors

E1105-00(R2008) ........Field Determination of Water Penetration of

Installed Exterior Windows, Curtain Walls, and

Doors By Uniform or Cyclic Static Air Pressure

Differences

E. American Welding Society, Inc. (AWS):

D1.2/D.1.2M-06(R2014) ..Structural Welding Code-Aluminum

F. Military Specifications (MIL):

MIL-C-18480 ............(Rev. B) Coating Compound, Bituminous Solvent, Coal Tar Base

G. National Association of Architectural Metal Manufacturers (NAAMM):

500 Series (2006) ......Metal Finishes Manual

H. Steel Structures Painting Council (SSPC)

Paint 25-97 (2004) .....Red Iron Oxide Raw Linseed Oil and Alkyd Primer

(Without Lead and Chromate Pigments)

I. U.S. Veterans Administration:

Physical Security Design Manual for VA Facilities (VAPSDG); Life Safety

Protected

J. Environmental Protection Agency (EPA):

40 CFR 59(2014) ........National Volatile Organic Compound Emission

Standards for Consumer and Commercial Products

1.8 WARRANTY:

A. Construction Warranty: Comply with FAR clause 52.246-21, “Warranty of

Construction”.

B. Manufacturer Warranty: Manufacturer shall warranty their glazed aluminum curtain wall system for a minimum of five (5) years from date

08 44 13 - 9 of installation and final acceptance by the Government. Submit manufacturer warranty.

PART 2 - PRODUCTS

2.1 SYSTEM DESCRIPTION:

A. Design Requirements:

1. Curtain Wall System: Tubular aluminum sections with thermal break condition supplementary support framing, factory prefinished, glass; related flashings, anchorage and attachment devices.

2. System Assembly: Site assembled.

3. Maximum wall framing member deflection, in a direction normal to plane of wall: 1/175 of its clear span or 20 mm (3/4 inch), whichever is less, when designed in accordance with requirements of

AAMA TIR A11 and tested in accordance with ASTM E330/E330M.

4. Maximum wall framing member deflection when a gypsum wallboard surface is affected: 1/360 of span.

5. Maximum Framing Member Permanent Deformation: 0.2 percent of its clear span when tested in accordance with ASTM E330/E330M for a minimum test period of 10 seconds at 1.5 times design wind pressures indicated as part of structural drawing wind load requirements.

B. No glass breakage, or damage to fasteners, hardware or accessories is permitted due to deformation design requirements indicated.

a. Provide system complete with framing, mullions, trim, fasteners, anchors, accessories, concealed auxiliary members, and attachment devices for securing wall to structure as specified or indicated. Unless noted otherwise, comply with AAMA MCWM-1.

b. Obtain all components of curtain wall system, including framing entrances from single manufacturer.

c. Fully coordinate system accessories directly incorporated and adjacent to contiguous related work and ensure materials compatibility, deflection limitations, thermal movements, and clearances and tolerances as indicated or specified. Coordinate continuity with adjacent thermal, weather, air and vapor barriers.

d. Provide system with adequate allowances for expansion and contraction of components and fastenings to prevent buckling damage, joint seal failure, glass breakage, undue stress on fastenings or other detrimental effects. For design purposes, 08 44 13 - 10 base provisions for thermal movement on assumed ambient temperature range of from -18 degrees C to 49 degrees C (0 degrees F to 120 degrees F).

e. Provide wall system to accommodate tolerances in building frame and other contiguous work as indicated or specified.

C. Calculations: Submit professionally prepared calculations to indicate how design requirements for structural loading, thermal, and other performance criteria have been satisfied.

2.2 PERFORMANCE REQUIREMENTS:

A. Delegated Design: Engage a qualified Professional Engineer, to design glazed aluminum curtain walls.

B. Conform with system performance requirements specified.

C. Blast Hazard Mitigation Design Criteria and Structural Performance:

1. General:

a. The glazed aluminum curtain wall including connections shall be designed, fabricated, and installed to resist the required directly applied blast loads.

b. Design of mullions may be performed using inelastic dynamic structural analysis methods. If this approach is used, a linearly decaying load shall be applied to the window area and the resulting dynamic window edge reactions should be applied to the resisting mullion.

c. As an alternative to the inelastic dynamic structural analysis approach, the load may be applied to the tributary area of the mullion; however this method may result in an overly conservative design.

d. Dynamic blast loads shall be considered as an independent load case; however, designing to meet the blast requirements does not eliminate the need to design the framing members to meet all other applicable loading conditions within limits and under conditions indicated in the respective sections.

2. Blast Loads: Linearly decaying peak pressure of GP1.

a. The magnitude of GP1 are defined in the Physical Security Design Standards Data Definitions, a document separate from this Manual. It is provided on a need-to-know basis to the blast/structural engineers performing analysis and design of VA projects. Authorized users can contact the Office of Construction and Facilities Management (CFM) in VA to request the document.

3. Performance Criteria:

a. Glazing: Design, fabricate, and install glass units to comply with the GSA condition 3B - ASTM F1642-12 Low Hazard. After glass breakage occurs in response to full design blast loading, glass fragments that enter space shall land on the floor no further than 10 feet from the framing systems.

b. Glazed Aluminum Curtain Wall: Window and curtain wall frame blast loads shall be computed as the Glass Maximum Capacity

08 44 13 - 11 specified in the Blast Loads section above, but not less than the actual design blast load.

1) Glass Maximum Capacity: The highest dynamic load at which the glass cracks but is retained by the frame. The glass maximum capacity is associated with the rupture strength of the laminated glass interlayer. The dynamic Glass Maximum Capacity load shall utilize the same time duration as the specified blast load.

c. Design, fabricate, and install glazed aluminum curtain wall to comply with the following:

1) Rotation: Rotation of mullion ends shall not exceed 4 degrees (L/30) at Glass Maximum Capacity.

2) Ductility: Ductility of mullions shall not to exceed 10 at Glass Maximum Capacity.

4. Anchorage Design: The glazed window wall and curtain wall systems' connections shall be designed, fabricated, and installed to resist the blast loads specified in this Section within limits and under condition indicated.

a. Reaction Forces: Connections and anchorages to the precast panels or structure shall be engineered for the direct and rebound maximum capacity of the window, curtain wall, and atria framing members to ensure that connections and anchorages are never the weak link of the system. The maximum capacity of each framing member shall be calculated to account for the actual provided member section and material properties.

b. Design anchorages and connections to fully develop the calculated reaction forces following the procedures outlined in the latest versions of AISC Allowable Stress Design (ASD) or Load and Resistance Factor Design (LRFD) manuals for metal-to-metal connections/attachments and the latest version of ACI-318 for anchorage to concrete.

When using LRFD-based ACI-318 apply a load factor of 1.0 to the blast-induced window frame reactions obtained from dynamic analyses. When using the ASD manual to design connections/attachments for blast, allowable stresses can be increased by a factor of 1.7.

5. Aluminum Framing Members:

a. Minimum aluminum yield strength shall be as shown on Drawings but no less than 172 MPa (25,000 psi).

b. Snap on elements or other aluminum extrusions that are not structurally connected together to act as a single composite member shall not be considered in determining the structural capacity of the mullion.

c. The aluminum mullions shall be positively fastened to adequately transfer the blast end reaction forces across the connection between adjacent framing members.

6. Steel Framing Members:

a. Minimum steel yield strength shall be 248 MPa (36,000 psi) for steel bars used to reinforce vertical mullions of the windows and curtain walls, if determined necessary by calculation.

b. A dynamic enhancement factor of 1.2 may be applied to

08 44 13 - 12 the yield stress for steel members, to account for strain rate effects.

c. The reinforcing steel bars and the aluminum mullions shall be sufficiently structurally connected to transfer the collected blast loads across the interface between the members.

d. Composite section properties of mullion components may only be used if calculations demonstrate strain compatibility across the interface.

e. Combined section properties of mullion components may be used if calculations demonstrate deformation compatibility between the aluminum and steel components.

D. Provide curtain wall components tested in accordance with requirements below and meeting performance requirements specified.

1. Water Penetration:

a. No water penetration is to occur when wall is tested in accordance with ASTM E331 at a differential static test pressure of 20 percent of inward acting design wind pressure as indicated on structural drawings, but not less than 479 Pa (10 psf).

b. Make provision in wall construction for adequate drainage to outside of water leakage or condensation that occurs within outer face of wall. Leave drainage and weep openings in members and wall open during test.

2. Air Infiltration: Test glazed aluminum curtain wall system according to AAMA 503, which requires testing according to

ASTM E783.

a. Static-Air-Differential: 75 Pa (1.57 lbf/sq. ft.) minimum.

b. Air Leakage: 0.03 L/s per sq. m (0.06 cfm/sq. ft.) of surface maximum.

3. Deflections Test: ASTM E330/E330M, Procedure B:

a. No member is to deflect in a direction parallel to plane of wall, when carrying its full design load, more than an amount which will reduce edge cover or glass bite below 75 percent of design dimension. No member after deflection under full design load, is to have a clearance between itself and top of panel, glass, sash, or other part immediately below it less than 3 mm

(1/8 inch); clearance between member and an operable window or door is to be minimum 1.5 mm (1/16 inch).

4. Delamination Test:

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a. Adhesively bonded metal-faced panels are to show no evidence of delamination, warpage or other deterioration or damage when subjected to the six "Accelerated Aging Cycles" specified in

ASTM D1037.

5. Sound Attenuation Through Wall System (Exterior to Interior):

a. STC 50, measured in accordance with ASTM E413.

6. Physical Security Life Safety Protected Facilities:

a. Provide glazed aluminum curtain walls designed to meet or exceed the design and construction standards as provided in the

Physical Security Design Manual for VA Facilities: Life Safety

Protected.

1) Blast Resistance: Design level threat (W1) located at the standoff distance, but not greater than GP1.

2.3 MATERIALS:

A. Extruded Aluminum Framing Members: ASTM B221M (B221); 6063-T5 extruded aluminum for non-structural components or 6063-T6 extruded aluminum for structural members; temper and alloy as recommended by manufacturer.

B. Sheet Aluminum: ASTM B209M (B209); 6065-T5 temper and alloy as recommended by manufacturer.

1. Formed flashing and closures: Minimum 1.58 mm (0.062 inch) thick aluminum, in finish as selected.

2. Extruded sill members: Minimum 1.58 mm (0.062 inch) thick aluminum, in finish as selected.

C. Steel Sections: ASTM A36/A36M.

D. Primer: TS TT-P-645; red, for shop application and field touch-up.

E. Fasteners:

1. For Exterior Cap Retainers: ASTM A193/A193M B8 300 series, stainless steel screws.

2. For Framework Connections: ASTM B211M (B211) 2024-T4 aluminum, ASTM A193/A193M B8 300 series, stainless steel, and ASTM B316 aluminum rivets, as required by connection.

3. For Anchoring Glazed Aluminum Curtain Wall to Support Structure:

ASTM A307 zinc plated steel fasteners.

F. Shims: Metal or plastic.

G. Joint Sealants and Accessories:

08 44 13 - 14

1. In accordance with requirements specified in Section 07 92 00, JOINT SEALANTS.

2. Structural Flush Glazed Joints: High performance silicone sealant applied in accordance with manufacturer's recommendations.

3. Non-structural Flush Glazed Joints and Weather Seal Joints:

Silicone sealants applied in accordance with manufacturer's recommendations.

4. Sealants used inside the weatherproofing system are to have a VOC content of 250 g/L or less when calculated according to 40 CFR 59, (EPA Method 24).

5. Structural silicone sealant performance requirements: ASTM C920.

a. Hardness: Type A, 30 durometer.

b. Ultimate Tensile Strength: 1172 kPa (170 psi).

c. Tensile at 150% Elongation (of original bench mark distance):

55 kPa (80 psi).

d. Joint Movement Capability after 14 Day Cure: +/- 50%.

e. Peel Strength Aluminum, After 21 Day Cure: 599 g/mm

(34 pounds per inch).

6. Structural silicone is not be used to support dead weight of vertical glass or panels.

7. Comply with recommendations of sealant manufacturer for specific sealant selections.

8. Provide only sealants that have been tested per ASTM C794 to exhibit adequate adhesion to samples of glass and metal equivalent to those required for project.

9. Exposed Metal to Metal Joints: Silicone sealant selected from manufacturer’s standard colors.

H. Glazing Materials:

1. As specified under Section 08 80 00, GLAZING.

2. Glazing Gaskets:

a. Exterior: Continuous EPDM gaskets at each glass and spandrel panel.

b. Interior: Continuous, closed cell PVC foam sealant tape, sealed at corners.

3. Glass Sizes and Clearances:

a. Accommodate up to 25 mm (1 inch) glazing.

b. Sizes indicated are nominal. Verify actual sizes required by measuring frames. Coordinate dimensions for glass and glass

08 44 13 - 15 holding members to meet applicable minimum clearances as recommended by glass manufacturer. Do not nip glass to remove flares or to reduce oversized dimensions. All cutting is to occur in factory.

4. Glass Setting Materials:

a. Provide head bead and drive wedge required for glass installation to suit curtain wall system in accordance with manufacture’s recommendations.

I. Column Covers Exterior and Interior Surfaces: 1.5 mm (0.625 inch) thick prefinished aluminum, full contact pressure bonded to substrate ensuring flat surface, finish to match curtain wall mullion sections.

J. Firestopping: Refer to Section 07 84 00, FIRESTOPPING for requirements.

2.4 FABRICATION:

A. Curtain wall components are to be of materials and thickness indicated in construction documents. Details indicated are representative of required design and profiles. Maintain sightlines. Unless specifically indicated or specified otherwise, methods of fabrication and assembly are to be at discretion of curtain wall manufacturer. Perform fitting and assembling of components in shop to maximum extent practicable.

Anchorage devices are to permit adjustment in three directions. No exposed fasteners are permitted.

B. Joints: Joints exceeding +1.5 mm (+1/16") are to be mechanically fastened.

C. Ventilation and Drainage: Direct water leakage to exterior by means of concealed drainage system and weeps. Flashings and other materials used internally are to be nonstaining, noncorrosive, and nonbleeding.

D. Protection and Treatment of Metals:

1. Remove from metal surfaces lubricants used in fabrication and clean off other extraneous material before leaving shop.

2. Provide protection against galvanic action wherever dissimilar metals are in contact, except in case of aluminum in permanent contact with galvanized steel, zinc, stainless steel, or relatively small areas of white bronze. Paint contact surfaces with one coat bituminous paint conforming to MIL-C-18480 or apply appropriate caulking material or nonabsorptive, noncorrosive, and nonstaining tape or gasket between contact surfaces.

08 44 13 - 16

E. Metal sills and Closures: Fabricate accessories, spandrel panels, trim closures of sizes and shapes indicated from similar materials and finish as specified for wall system.

F. Concealed Interior Mullion Reinforcing: ASTM A36/A36M steel shapes as required for strength and mullion size limitations, hot dip galvanized after fabrication in accordance with ASTM A123/A123M.

PART 3 - EXECUTION

3.1 EXAMINATION:

A. Prior to installation of glazed curtain wall system, arrange for representative(s) of manufacturer to examine structure and substrate to determine that they are properly prepared, and ready to receive glazed curtain wall work included herein.

B. Verifying Conditions and Adjacent Surfaces: After establishment of lines and grades and prior to system installation examine supporting structural elements. Verify governing dimensions, including floor elevations, floor to floor heights, minimum clearances between curtain wall and structural frames, and other permissible dimensional tolerances in building frame.

3.2 PREPARATION:

A. Take field dimensions and examine condition of substrates, supports, and other conditions under which work of this section is to be performed to verify that work may properly commence. Do not proceed with installation until unsatisfactory conditions have been corrected.

B. Contact between aluminum and dissimilar metals are to receive a protective coating of bituminous paint for prevention of electrolytic action and corrosion.

3.3 INSTALLATION:

A. Install and erect glazed curtain wall system and all components in accordance with written directions of curtain wall manufacturer. Match profiles, sizes, and spacing indicated on approved shop drawings.

B. Bench Marks and Reference Points: Establish and permanently mark bench marks for elevations and building line offsets for alignment at convenient points on each floor level. Should any error or discrepancy be discovered in location of marks, stop erection work in that area until discrepancies have been corrected.

C. Ensure that drainage system operates properly in accord with AAMA 501 procedures.

08 44 13 - 17

D. Do not proceed with structural silicone work when metal temperature is below 0 degrees C (32 degrees F).

E. Isolate between aluminum and dissimilar metals with protective coating or plastic strip to prevent electrolytic corrosion.

F. Install glazed aluminum curtain wall system so as to maintain a virtually flat face cap, with no visible bowing.

G. Install entire system so that fasteners are not visible.

H. Tolerances:

1. Maximum variation from plane or location shown on approved shop drawings: 3 mm per 3657 mm (1/8 inch per 12 feet) of length up to not more than 13 mm (1/2 inch) in any total length.

2. Maximum offset from true alignment between two (2) identical members abutting end to end in line: 0.8 mm (1/32 inch).

3. Sealant Space Between Curtain Wall Mullion and Adjacent

Construction: Maximum of 19 mm (3/4 inch) and minimum of 6 mm

(1/4 inch).

I. Joint Sealants:

1. Joint Sealants: Are to be in accordance with requirements of

Section 07 92 00, JOINT SEALANTS.

2. Surfaces to be primed and sealed are to be clean, dry to touch, free from frost, moisture, grease, oil, wax, lacquer, paint, or other foreign matter. Enclose joints on three sides. Clean out grooves to proper depth. Joint dimensions are to conform to approved detail drawings with a tolerance of plus 3 mm (1/8 inch).

Do not apply compound unless ambient temperature is between 5 and

35 degrees C (40 and 90 degrees F). Clean out loose particles and mortar just before sealing. Remove protective coatings or coverings from surfaces in contact with sealants before applying sealants or tapes. Solvents used to remove coatings are to be of type that leave no residue on metals.

3. Match approved sample. Force compound into grooves with sufficient pressure to fill grooves solidly. Sealing compound is to be uniformly smooth and free of wrinkles and, unless indicated otherwise, is to be tooled and left sufficiently convex to result in a flush joint when dry. Do not trim edges of sealing material after joints are tooled. Mix only amount of multi-component sealant which can be installed within four (4) hours, but at no time is this amount exceed 19 liters (5 gallons).

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4. Apply primer to masonry, concrete, wood, and other surfaces as recommended by sealant manufacturer. Do not apply primer to surfaces which will be exposed after sealant work is completed.

5. Tightly pack backing in bottom of joints which are over 13 mm

(1/2 inch) in depth with specified backing material to depth indicated in construction documents. Roll backing material of hose or rod stock into joints to prevent lengthwise stretching.

6. Install bond preventive material at back or bottom of joint cavities in which no backstop material is required, covering full width and length of joint cavities.

7. Remove compound smears from surfaces of materials adjacent to sealed joints as work progresses. Use masking tape on each side of joint where texture of adjacent material will be difficult to clean. Remove masking tape immediately after filling joint. Scrape off fresh compound from adjacent surfaces immediately and rub clean with solvent approved by sealant and curtain wall manufacturers.

Upon completion of sealing, remove remaining smears, stains, and other soiling, and leave work in clean neat condition.

J. Glass:

1. Refer to Section 08 80 00, GLAZING, and drawings for glass types.

Install in accordance with manufacturer's recommendations as modified herein.

2. Before installing glass, inspect sash and frames to receive glass for defects such as dimensional variations, glass clearances, open joints, or other conditions that will prevent satisfactory glass installation. Do not proceed with installation until defects have been corrected.

3. Clean sealing surfaces at perimeter of glass and sealing surfaces of rebates and stop beads before applying glazing compound, sealing compound, glazing tape, or gaskets.

4. Use only approved solvents and cleaning agents recommended by compound or gasket manufacturer and by curtain wall manufacturer.

5. Provide sashes designed for outside glazing.

6. Provide continuous snap in glazing beads to suit glass as specified.

7. Insulating and tempered glass, and glass of other types that exceed

2540 mm (100 united inches) in size: Provide void space at head and jamb to allow glass to expand or move without exuding sealant.

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Provide perimeter frames and ventilator sections with glazing rebates for unobstructed glazing surface 19 mm (3/4 inch) in height. Glazing rebate surfaces must be sloped to shed water.

8. Provide adequate means to weep incidental water and condensation away from sealed edges of insulated glass units and out of wall system. Provide weeping of lock-strip gaskets in accordance with recommendation of glass manufacturer.

K. Metal Copings:

1. Refer to Section 07 60 00, FLASHING AND SHEET METAL for requirements of metal copings when they are not a part of glazed curtain wall system work.

2. Coordinate curtain wall installation with metal coping detail on construction documents. Provide watertight seal to meet criteria set forth in this section regarding air and water penetration.

3.4 ADJUSTING:

A. Adjust doors to provide a tight fit at contact points and operate easily.

B. Adjust weather-stripping to make even contact with surfaces.

C. Adjust operating hardware and moving parts.

3.5 CLEANING:

A. Install curtain wall frame and associated metal to avoid soiling or smudging finish.

B. Clean metal surfaces promptly after installation, exercising care to avoid damage to coatings.

C. Remove excess glazing and sealant compounds, dirt, and other substances.

D. Follow recommendations of manufacturer in selection of cleaning agents. Do not use cleaning agents containing ammonia or other compounds that might damage finished metal surfaces.

E. Replace cracked, broken, and defective glass with new glass at no additional cost to Government. Just prior to final acceptance of curtain wall system clean glass surfaces on both sides, remove labels, paint spots, compounds, and other defacements, and clean metal fixed panels. Remove and replace components that cannot be cleaned successfully.

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3.6 FIELD QUALITY CONTROL:

A. Testing Agency: Engage an AAMA accredited commercial qualified independent testing and inspecting agency to perform field quality-control tests specified, and to prepare test reports: Submit information regarding testing laboratory's facilities and qualifications of technical personnel to Resident Engineer for approval.

B. Conduct field check test for water leakage on designated wall areas after erection to comply with AAMA MCWM-1. Conduct test on two (2) wall areas, two (2) bays wide by two (2) stories high where directed.

Conduct test and take necessary remedial action as directed by

Resident Engineer.

C. Test Specimen:

1. Test specimen is to include curtain wall assembly and construction.

Test chamber is to be affixed to exterior side of test specimen and test is to be conducted using positive static air pressure.

2. Test specimens are to be selected by Resident Engineer after curtain wall system has been installed in accordance with construction documents.

D. Sealant Adhesion Tests: Test installed sealant, in presence of sealant manufacturer’s field representative, in a minimum of two (2) areas and as follows:

1. Test structural silicone sealant according to field adhesion test method described in AAMA CW 13.

2. Test weatherseal sealant adhesion to joint substrates according to

Method A, Field-Applied Sealant Joint Hand Pull Tab, in Appendix X1 in ASTM C1193 or Method A, Tail Procedure, in ASTM C1521.

E. Air Infiltration: Test glazed aluminum curtain wall system according to AAMA 503, which requires testing according to ASTM E783 and to values indicated below, whichever is more stringent.

1. Field air leakage testing is not required for continuous curtain wall systems.

2. Static-Air-Pressure Differential: 75 Pa (1.57 lbf/sq. ft.) minimum.

3. Air Leakage: 0.03 L/s per sq. m (0.06 cfm/sq. ft.) of surface maximum.

F. Water Penetration: Test glazed aluminum curtain wall system for compliance with requirements according to AAMA 503, which requires testing according to ASTM E1105.

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1. Uniform Static-Air-Pressure Difference: 20 percent of positive design wind load, but not less than 479 Pa (10 psf). No uncontrolled water is to be present.

G. Retesting:

1. Should system fail field test, system may be modified or repaired, and retested.

2. Should system fail second field test, system may be additionally modified or repaired, and retested.

3. All modifications and repairs made to tested areas are to be recorded, and same modifications and repairs made to all system and adjacent construction on project.

4. Should second test fail, Resident Engineer may require testing of additional areas of the curtain wall.

H. Rejection:

1. Failure of any of specimens to meet test requirements of third test is cause for rejection of wall system and adjacent construction on project.

3.7 PROTECTION:

A. After installation, protect windows, and other exposed surfaces from disfiguration, contamination, contact with harmful materials, and from other construction hazards that will interfere with their operation, or damage their appearance or finish. Protection methods are to be in accordance with recommendations of product manufacturers or of respective trade association. Remove paper or tape factory applied protection immediately after installation. Clean surfaces of mortar, plaster, paint, smears of sealants, and other foreign matter to present neat appearance and prevent fouling of operation. In addition, wash with a stiff fiber brush, soap and water, and thoroughly rinse.

Where surfaces become stained or discolored, clean or restore finish in accordance with recommendations of product manufacturer or respective trade association.

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