Denver Museum of Nature and Science: Education and Collections Facility klipp, a professional corporation Project number 2009.104 Addendum #4100% Construction Documents
SECTION 055100 - METAL STAIRS PART 1 - GENERAL 1.1
RELATED DOCUMENTS A.
1.2
Drawings and general provisions of the Contract, including General and Supplementary Conditions and Division 01 Specification Sections, apply to this Section. SUMMARY
A.
This Section includes the following: 1. 2. 3. 4.
B.
Related Sections include the following: 1. 2. 3. 4. 5. 5.6.
1.3
Preassembled steel stairs with concrete-filled treads. Industrial-type stairs with steel grate treads. Steel tube railings attached to metal stairs. Railing gates at the level of exit discharge.
Division 03 Section "Cast-in-Place Concrete" for concrete fill for stair treads and platforms. Division 05 Section "Metal Fabrications" for metal treads and nosings not installed in metal stairs. Division 05 Section "Pipe and Tube Railings" for pipe and tube railings. Division 05 Section "Pipe and Tube Railings" for pipe and tube railings not attached to metal stairs or to walls adjacent to metal stairs. Division 05 Section “Decorative Metal and Glass Railings” Division 09 Section "Gypsum Board Shaft-Wall Assemblies" for metal backing for anchoring railings.
PERFORMANCE REQUIREMENTS A.
Structural Performance of Stairs: Provide metal stairs capable of withstanding the effects of gravity loads and the following loads and stresses within limits and under conditions indicated: 1. 2. 3. 4. 5.
B.
Uniform Load: 100 lbf/sq. ft.. Concentrated Load: 300lbf applied on an area of 4 sq. in. Uniform and concentrated loads need not be assumed to act concurrently. Stair Framing: Capable of withstanding stresses resulting from railing loads in addition to loads specified above. Limit deflection of treads, platforms, and framing members to L/360 or 1/4 inch whichever is less.
Structural Performance of Railings: Provide railings capable of withstanding the effects of gravity loads and the following loads and stresses within limits and under conditions indicated:
METAL STAIRS
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Denver Museum of Nature and Science: Education and Collections Facility klipp, a professional corporation Project number 2009.104 Addendum #4100% Construction Documents
1.
Handrails: a. b. c.
2.
Top Rails of Guards: a. b. c.
3.
1.4
Uniform load of 50 lbf/ ft. applied in any direction. Concentrated load of 200 lbf applied in any direction. Uniform and concentrated loads need not be assumed to act concurrently.
Infill of Guards: a. b. c.
C.
Uniform load of 50 lbf/ ft. applied in any direction. Concentrated load of 200 lbf applied in any direction. Uniform and concentrated loads need not be assumed to act concurrently.
Concentrated load of 200 lbf applied horizontally on an area of 1 sq. ft.. Uniform load of 25 lbf/sq. ft. applied horizontally. Infill load and other loads need not be assumed to act concurrently.
Seismic Performance: Provide metal stairs capable of withstanding the effects of earthquake motions determined according to ASCE 7, "Minimum Design Loads for Buildings and Other Structures" : Section 9, "Earthquake Loads." . SUBMITTALS
A.
Product Data: For metal stairs and the following: 1. 2. 3.
B.
Prefilled metal-pan stair treads. Paint products. Grout.
Shop Drawings: Include plans, elevations, sections, details, and attachments to other work. 1. 2.
Provide templates for anchors and bolts specified for installation under other Sections. For installed products indicated to comply with design loads, include structural analysis data signed and sealed by the qualified professional engineer responsible for their preparation.
C.
Welding certificates.
D.
Qualification Data: For professional engineer.
E.
Product Test Reports: Based on evaluation of comprehensive tests performed by a qualified testing agency, for stairs and railings. 1.
Test railings according ASTM E 894 and ASTM E 935.
F. LEED Submittals: 1.
METAL STAIRS
Product Data for Recycled Content (MRc4)
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Denver Museum of Nature and Science: Education and Collections Facility klipp, a professional corporation Project number 2009.104 Addendum #4100% Construction Documents
a. Submit product data or other published information indicating total weight of product to be provided for the Project, percent of post-consumer recycled material by weight and percent of post-industrial recycled material by weight. Include material costs (excluding costs of installation). G.
Low-Emitting Paints and Coatings (EQc4.2) 1. Submit product data or other published information verifying the VOC (Volatile Organic Compound) content is less than or equal to the allowable VOC content established by the governing standards
1.5
QUALITY ASSURANCE A.
Installer Qualifications: Fabricator of products.
B.
NAAMM Stair Standard: Comply with "Recommended Voluntary Minimum Standards for Fixed Metal Stairs" in NAAMM AMP 510, "Metal Stairs Manual," for class of stair designated, unless more stringent requirements are indicated. 1. 2.
C.
Welding: Qualify procedures and personnel according to the following: 1. 2.
1.6
Preassembled Stairs: Commercial class. Industrial-Type Stairs: Industrial class.
AWS D1.1, "Structural Welding Code--Steel." AWS D1.3, "Structural Welding Code--Sheet Steel."
COORDINATION A.
Coordinate installation of anchorages for metal stairs. Furnish setting drawings, templates, and directions for installing anchorages, including sleeves, concrete inserts, anchor bolts, and items with integral anchors, that are to be embedded in concrete or masonry. Deliver such items to Project site in time for installation.
B.
Coordinate locations of hanger rods and struts with other work so that they will not encroach on required stair width and will be within the fire-resistance-rated stair enclosure.
PART 2 - PRODUCTS 2.1
METALS, GENERAL A.
Metal Surfaces, General: Provide materials with smooth, flat surfaces, unless otherwise indicated. For components exposed to view in the completed Work, provide materials without seam marks, roller marks, rolled trade names, or blemishes.
METAL STAIRS
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2.2
FERROUS METALS A.
Steel Plates, Shapes, and Bars: ASTM A 36/A 36M.
B.
Steel Tubing: ASTM A 500 (cold formed).
C.
Rolled-Steel Floor Plate: ASTM A 786/A 786M, rolled from plate complying with ASTM A 36/A 36M or ASTM A 283/A 283M, Grade C or D.
D.
Abrasive-Surface Floor Plate: Steel plate with abrasive granules rolled into surface or with abrasive material metallically bonded to steel by a proprietary process. 1.
Available Products: a. b.
IKG Industries, a Harsco company; Mebac. W. S. Molnar Company; SlipNOT.
E.
Steel Bars for Grating Treads: ASTM A 36/A 36M.
F.
Wire Rod for Grating Crossbars: ASTM A 510.
G.
Iron Castings: Either gray or malleable iron, unless otherwise indicated. 1. 2.
Gray Iron: ASTM A 48/A 48M, Class 30, unless another class is indicated or required by structural loads. Malleable Iron: ASTM A 47/A 47M.
H.
Uncoated, Cold-Rolled Steel Sheet: ASTM A 1008/A 1008M, structural steel, Grade 25, unless another grade is required by design loads; exposed.
I.
Uncoated, Hot-Rolled Steel Sheet: ASTM A 1011/A 1011M structural steel, Grade 30, unless another grade is required by design loads.
J.
Galvanized Steel Sheet: ASTM A 653/A 653M, G90 coating, structural steel, Grade 33, unless another grade is required by design loads.
K.
Recycled Content (MRc4) 1. Minimum 25% total recycled content.
2.3
NONFERROUS METALS A.
Aluminum Extrusions: ASTM B 221, Alloy 6063-T6.
B.
Aluminum Castings: ASTM B 26/B 26M, Alloy 443.0-F.
C.
Bronze Extrusions: ASTM B 455, Alloy UNS No. C38500 (extruded architectural bronze).
D.
Bronze Castings: ASTM B 584, Alloy UNS No. C83600 (leaded red brass) or No. C84400 (leaded semired brass).
METAL STAIRS
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Denver Museum of Nature and Science: Education and Collections Facility klipp, a professional corporation Project number 2009.104 Addendum #4100% Construction Documents
E.
2.4
Nickel Silver Castings: bronze).
ASTM B 584, Alloy UNS No. C97600 (20 percent leaded nickel
FASTENERS A.
General: Provide zinc-plated fasteners with coating complying with ASTM B 633, Class Fe/Zn 25 for exterior use, and Class Fe/Zn 5 where built into exterior walls. Select fasteners for type, grade, and class required.
B.
Bolts and Nuts: Regular hexagon-head bolts, ASTM A 307, Grade A; with hex nuts, ASTM A 563; and, where indicated, flat washers.
C.
Anchor Bolts: ASTM F 1554, Grade 36. 1.
Provide hot-dip or mechanically deposited, zinc-coated anchor bolts for stairs indicated to be galvanized.
D.
Machine Screws: ASME B18.6.3.
E.
Lag Bolts: ASME B18.2.1.
F.
Plain Washers: Round, ASME B18.22.1.
G.
Lock Washers: Helical, spring type, ASME B18.21.1.
H.
Expansion Anchors: Anchor bolt and sleeve assembly with capability to sustain, without failure, a load equal to six times the load imposed when installed in unit masonry and four times the load imposed when installed in concrete, as determined by testing according to ASTM E 488, conducted by a qualified independent testing agency. 1. 2.
2.5
Material for Anchors in Interior Locations: Carbon-steel components zinc-plated to comply with ASTM B 633, Class Fe/Zn 5. Material for Anchors in Exterior Locations: Alloy Group 1 stainless-steel bolts complying with ASTM F 593 and nuts complying with ASTM F 594.
MISCELLANEOUS MATERIALS A.
Welding Rods and Bare Electrodes: Select according to AWS specifications for metal alloy welded.
B.
Shop Primers: Provide primers that comply with Division 09 painting Sections. Select paragraph above or one or both primer paragraphs and associated subparagraphs below. First paragraph below specifies a typical primer for painted finishes that provides minimum protection to steel. Second paragraph specifies a typical primer for high-performance coating. If retaining both, indicate on Drawings or in a schedule where each is required.
C.
Universal Shop Primer: Fast-curing, lead- and chromate-free, universal modified-alkyd primer complying with MPI#79.
METAL STAIRS
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Denver Museum of Nature and Science: Education and Collections Facility klipp, a professional corporation Project number 2009.104 Addendum #4100% Construction Documents
1. 2. D.
Use primer with a VOC content of 420 g/L (3.5 lb/gal.) or less when calculated according to 40 CFR 59, Subpart D (EPA Method 24). Use primer containing pigments that make it easily distinguishable from zinc-rich primer.
Low-Emitting Paints and Coatings (EQc4.2) 1. Submit product data or other published information verifying the VOC (Volatile Organic Compound) content is less than or equal to the allowable VOC content established by the governing standard.
D.E. Zinc-Rich Primer: Complying with SSPC-Paint 20 or SSPC-Paint 29 and compatible with topcoat. 1. 2.
Use primer with a VOC content of 420 250 g/L (3.5 lb/gal.) or less when calculated according to 40 CFR 59, Subpart D (EPA Method 24). Products: a. b. c. d. e. f. g.
Carboline Company; Carbozinc 621. ICI Devoe Coatings; Catha-Coat 313. International Coatings Limited; Interzinc 315 Epoxy Zinc-Rich Primer. Moore, Benjamin, & Co.; Epoxy Zinc-Rich Primer CM18/19. PPG Architectural Finishes, Inc.; Aquapon Zinc-Rich Primer 97-670. Sherwin-Williams Company (The); Corothane I GalvaPac Zinc Primer. Tnemec Company, Inc.; Tneme-Zinc 90-97.
E.F. Galvanizing Repair Paint: High-zinc-dust-content paint for regalvanizing welds in steel, complying with SSPC-Paint 20. F.G. Bituminous Paint: Cold-applied asphalt emulsion complying with ASTM D 1187. G.H. Nonshrink, Nonmetallic Grout: Factory-packaged, nonstaining, noncorrosive, nongaseous grout complying with ASTM C 1107. Provide grout specifically recommended by manufacturer for interior and exterior applications. H.I.
Concrete Materials and Properties: Comply with requirements in Division 03 Section "Cast-inPlace Concrete" for normal-weight, air-entrained, ready-mix concrete with a minimum 28-day compressive strength of 3000 psi, unless otherwise indicated.
I.J.
Nonslip-Aggregate Concrete Finish: Factory-packaged abrasive aggregate made from fused, aluminum-oxide grits or crushed emery; rustproof and nonglazing; unaffected by freezing, moisture, or cleaning materials.
J.K. Welded Wire Fabric: ASTM A 185, 6 by 6 inches --W1.4 by W1.4, unless otherwise indicated. 2.6
FABRICATION, GENERAL A.
Provide complete stair assemblies, including metal framing, hangers, struts, railings, clips, brackets, bearing plates, and other components necessary to support and anchor stairs and platforms on supporting structure. 1.
METAL STAIRS
Join components by welding, unless otherwise indicated. 055100 - 6
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2. 3.
Use connections that maintain structural value of joined pieces. Fabricate treads and platforms of exterior stairs so finished walking surfaces slope to drain.
B.
Preassembled Stairs: Assemble stairs in shop to greatest extent possible. Disassemble units only as necessary for shipping and handling limitations. Clearly mark units for reassembly and coordinated installation.
C.
Cut, drill, and punch metals cleanly and accurately. Remove burrs and ease edges to a radius of approximately 1/32 inch, unless otherwise indicated. Remove sharp or rough areas on exposed surfaces.
D.
Form bent-metal corners to smallest radius possible without causing grain separation or otherwise impairing work.
E.
Form exposed work true to line and level with accurate angles and surfaces and straight edges.
F.
Weld connections to comply with the following: 1. 2. 3. 4. 5.
Use materials and methods that minimize distortion and develop strength and corrosion resistance of base metals. Obtain fusion without undercut or overlap. Remove welding flux immediately. Weld exposed corners and seams continuously, unless otherwise indicated. At exposed connections, finish exposed welds and surfaces smooth and blended so no roughness shows after finishing and contour of welded surface matches that of adjacent surface.
G.
Form exposed connections with hairline joints, flush and smooth, using concealed fasteners where possible. Where exposed fasteners are required, use Phillips flat-head (countersunk) screws or bolts unless otherwise indicated. Locate joints where least conspicuous.
H.
Fabricate joints that will be exposed to weather in a manner to exclude water. Provide weep holes where water may accumulate.
2.7
STEEL-FRAMED STAIRS A.
Manufacturers: 1. 2. 3.
B.
Alfab, Inc. American Stair, Inc. Sharon Companies Ltd. (The).
Stair Framing: 1.
Fabricate stringers of steel plates or channels to hold dimension indicated on the drawings. a.
METAL STAIRS
Provide closures for exposed ends of channel stringers.
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2. 3. 4.
5.
C.
Construct platforms of steel plate or channel headers and miscellaneous framing members as needed to comply with performance requirements. Weld stringers to headers; weld or bolt framing members to stringers and headers. Where stairs are enclosed by gypsum board shaft-wall assemblies, provide hanger rods or struts to support landings from floor construction above or below. Locate hanger rods and struts where they will not encroach on required stair width and will be within the fire-resistance-rated stair enclosure. Where masonry walls support metal stairs, provide temporary supporting struts designed for erecting steel stair components before installing masonry.
Metal-Pan Stairs: Form risers, subtread pans, and subplatforms to configurations shown from steel sheet of thickness needed to comply with performance requirements but not less than 0.0677 inch. 1. 2. 3. 4. 5. 6. 7.
Steel Sheet: Uncoated cold-rolled steel sheet, unless otherwise indicated. Directly weld metal pans to stringers; locate welds on top of subtreads where they will be concealed by concrete fill. Do not weld risers to stringers. Attach risers and subtreads to stringers with brackets made of steel angles or bars. Weld brackets to stringers and attach metal pans to brackets by welding, riveting, or bolting. Shape metal pans to include nosing integral with riser. Attach abrasive nosings to risers. At Contractor's option, provide stair assemblies with metal-pan subtreads filled with reinforced concrete during fabrication. Provide subplatforms of configuration indicated or, if not indicated, the same as subtreads. Weld subplatforms to platform framing. a.
D.
Abrasive-Coating-Finished, Formed-Metal Stairs: Form risers, treads, and platforms to configurations shown from steel sheet of thickness needed to comply with performance requirements but not less than 0.0966 inch. 1. 2. 3. 4.
E.
Smooth Soffit Construction: Construct subplatforms with smooth soffits.
Steel Sheet: Uncoated hot-rolled steel sheet, unless otherwise indicated. Directly weld risers and treads to stringers; locate welds on underside of stairs. Provide platforms of configuration indicated or, if not indicated, the same as treads. Weld platforms to platform framing. Finish tread and platform surfaces with manufacturer's standard epoxy-bonded abrasive finish.
Metal Bar-Grating Stairs: Form treads and platforms to configurations shown from metal bar grating; fabricate to comply with NAAMM MBG 531, "Metal Bar Grating Manual." 1.
2.
3. 4.
METAL STAIRS
Fabricate treads and platforms from welded steel grating with 1-1/4-by-3/16-inch bearing bars at 15/16 incho.c. and crossbars at 4 inches o.c., NAAMM designation: W-15-4 (11/4 x 3/16) STEEL. Fabricate treads and platforms from pressure-locked steel grating with 1-by-3/16-inch bearing bars at 11/16 inch o.c. and crossbars at 4 inches o.c., NAAMM designation: P11-4 (1 x 3/16) STEEL. Surface: Plain. Finish: Galvanized.
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5. 6.
2.8
Fabricate grating treads with rolled-steel floor plate nosing and with steel angle or steel plate carrier at each end for stringer connections. Secure treads to stringers with bolts. Fabricate grating platforms with nosing matching that on grating treads. Provide toeplates at open-sided edges of grating platforms. Weld grating to platform framing.
STEEL TUBE RAILINGS A.
General: Fabricate railings to comply with requirements indicated for design, dimensions, details, finish, and member sizes, including wall thickness of tube, post spacings, and anchorage, but not less than that needed to withstand indicated loads. 1. 2.
Configuration: 1-5/8-inch- diameter top and bottom rails, 1-1/2-inch- square posts, and 1/2-inch- square pickets spaced less than 4 inches clear. Configuration: 1-1/2-inch- square top and bottom rails and posts with infill panels made from expanded metal. a. b.
3.
Configuration: 1-1/2-inch- square top and bottom rails and posts with infill panels made from woven wire mesh crimped into 1-by-1/2-by-1/8-inch steel channel frames. a.
4. 5. 6.
Edge panels with U-shaped channels made from steel sheet not less than 0.0428 inch thick. Orient expanded metal with long dimension of diamonds [parallel to top rail] [perpendicular to top rail] [vertical].
Orient wire mesh with [diamonds vertical] [wires perpendicular and parallel to top rail] [wires horizontal and vertical].
Configuration: 1-1/2-inch square top, bottom, and intermediate rails and posts. Space intermediate rails less than [12 inches] [21 inches] clear. Configuration: 1-5/8-inch- iameter top, bottom, and intermediate rails and 1-1/2-inchsquare posts. Space intermediate rails less than [12 inches] [21 inches] clear. Gates: Form gates from steel tube of same size and shape as top rails, with infill to match guards. Provide with [cam-type self-closing] [spring] hinges for fastening to wall and overlapping stop with rubber bumper to prevent gate from opening in direction opposite egress.
B.
Welded Connections: Fabricate railings with welded connections. Cope components at connections to provide close fit, or use fittings designed for this purpose. Weld all around at connections, including at fittings.
C.
Form changes in direction of railings as follows: 1. 2. 3. 4. 5.
METAL STAIRS
As detailed. By bending[ or by inserting prefabricated elbow fittings]. By flush bends[ or by inserting prefabricated flush-elbow fittings]. By radius bends of radius indicated[ or by inserting prefabricated elbow fittings of radius indicated]. By inserting prefabricated [elbow fittings] [flush-elbow fittings] [elbow fittings of radius indicated].
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D.
Form simple and compound curves by bending members in jigs to produce uniform curvature for each repetitive configuration required; maintain cross section of member throughout entire bend without buckling, twisting, cracking, or otherwise deforming exposed surfaces of components.
E.
Close exposed ends of railing members with prefabricated end fittings.
F.
Provide wall returns at ends of wall-mounted handrails, unless otherwise indicated. Close ends of returns unless clearance between end of rail and wall is 1/4 inch or less.
G.
Brackets, Flanges, Fittings, and Anchors: Provide wall brackets, end closures, flanges, miscellaneous fittings, and anchors for interconnecting components and for attaching to other work. Furnish inserts and other anchorage devices for connecting to concrete or masonry work. 1. 2. 3.
H.
2.9
Connect posts to stair framing by direct welding, unless otherwise indicated. For galvanized railings, provide galvanized fittings, brackets, fasteners, sleeves, and other ferrous-metal components. For nongalvanized railings, provide nongalvanized ferrous-metal fittings, brackets, fasteners, and sleeves, except galvanize anchors embedded in exterior masonry and concrete construction.
Fillers: Provide fillers made from steel plate, or other suitably crush-resistant material, where needed to transfer wall bracket loads through wall finishes to structural supports. Size fillers to suit wall finish thicknesses and to produce adequate bearing area to prevent bracket rotation and overstressing of substrate. STAIR RAILINGS
A.
Comply with applicable requirements in Division 05 Section "Pipe and Tube Railings" for railings, and as follows: 1. 2. 3.
2.10
Fabricate newels of square steel tubing and provide newel caps of pressed steel, as shown. Rails may be bent at corners, rail returns, and wall returns, instead of using prefabricated fittings. Connect posts to stair framing by direct welding, unless otherwise indicated.
FINISHES
A.
Comply with NAAMM's "Metal Finishes Manual for Architectural and Metal Products" for recommendations for applying and designating finishes.
B.
Finish metal stairs after assembly.
C.
Galvanizing: Hot-dip galvanize items as indicated to comply with applicable standard listed below: 1. 2.
METAL STAIRS
ASTM A 123/A 123M, for galvanizing steel and iron products. ASTM A 153/A 153M, for galvanizing steel and iron hardware.
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3.
D.
Preparation for Shop Priming: Prepare uncoated ferrous-metal surfaces to comply with minimum requirements indicated below for SSPC surface preparation specifications and environmental exposure conditions of installed products: 1. 2. 3.
E.
Fill vent and drain holes that will be exposed in finished Work, unless indicated to remain as weep holes, by plugging with zinc solder and filing off smooth.
Exterior Stairs (SSPC Zone 1B): SSPC-SP 6/NACE No. 3, "Commercial Blast Cleaning." Interior Stairs (SSPC Zone 1A): SSPC-SP 3, "Power Tool Cleaning." Interior Stairs (SSPC Zone 1A): SSPC-SP 6/NACE No. 3, "Commercial Blast Cleaning."
Apply shop primer to uncoated surfaces of metal stair components, except those with galvanized finishes and those to be embedded in concrete or masonry unless otherwise indicated. Comply with SSPC-PA 1, "Paint Application Specification No. 1: Shop, Field, and Maintenance Painting of Steel," for shop painting. 1.
Stripe paint corners, crevices, bolts, welds, and sharp edges.
PART 3 - EXECUTION 3.1
INSTALLATION, GENERAL A.
Fastening to In-Place Construction: Provide anchorage devices and fasteners where necessary for securing metal stairs to in-place construction. Include threaded fasteners for concrete and masonry inserts, through-bolts, lag bolts, and other connectors.
B.
Cutting, Fitting, and Placement: Perform cutting, drilling, and fitting required for installing metal stairs. Set units accurately in location, alignment, and elevation, measured from established lines and levels and free of rack.
C.
Install metal stairs by welding stair framing to steel structure or to weld plates cast into concrete, unless otherwise indicated.
D.
Provide temporary bracing or anchors in formwork for items that are to be built into concrete, masonry, or similar construction.
E.
Fit exposed connections accurately together to form hairline joints. Weld connections that are not to be left as exposed joints but cannot be shop welded because of shipping size limitations. Do not weld, cut, or abrade surfaces of exterior units that have been hot-dip galvanized after fabrication and are for bolted or screwed field connections.
F.
Field Welding: Comply with the following requirements: 1. 2. 3.
METAL STAIRS
Use materials and methods that minimize distortion and develop strength and corrosion resistance of base metals. Obtain fusion without undercut or overlap. Remove welding flux immediately.
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4.
G.
Place and finish concrete fill for treads and platforms to comply with Division 03 Section "Cast-in-Place Concrete." 1.
H. 3.2
At exposed connections, finish exposed welds and surfaces smooth and blended so no roughness shows after finishing and contour of welded surface matches that of adjacent surface.
Install abrasive nosings with anchors fully embedded in concrete. Center nosings on tread width.
Install precast concrete treads with adhesive supplied by manufacturer. INSTALLING METAL STAIRS WITH GROUTED BASEPLATES
A.
Clean concrete and masonry bearing surfaces of bond-reducing materials, and roughen to improve bond to surfaces. Clean bottom surface of baseplates.
B.
Set steel stair baseplates on wedges, shims, or leveling nuts. After stairs have been positioned and aligned, tighten anchor bolts. Do not remove wedges or shims but, if protruding, cut off flush with edge of bearing plate before packing with grout. 1. 2.
3.3
Use nonmetallic, nonshrink grout, unless otherwise indicated. Pack grout solidly between bearing surfaces and plates to ensure that no voids remain.
INSTALLING STEEL TUBE RAILINGS A.
Adjust railing systems before anchoring to ensure matching alignment at abutting joints. Space posts at spacing indicated or, if not indicated, as required by design loads. Plumb posts in each direction. Secure posts and rail ends to building construction as follows: 1. 2.
B.
Anchor posts to steel by welding directly to steel supporting members. Anchor handrail ends to concrete and masonry with steel round flanges welded to rail ends and anchored with postinstalled anchors and bolts.
Attach handrails to wall with wall brackets. Provide bracket with 1-1/2-inch clearance from inside face of handrail and finished wall surface. Locate brackets as indicated or, if not indicated, at spacing required to support structural loads. Secure wall brackets to building construction as follows: 1. 2. 3. 4. 5. 6.
METAL STAIRS
Use type of bracket with flange tapped for concealed anchorage to threaded hanger bolt. Use type of bracket with predrilled hole for exposed bolt anchorage. For concrete and solid masonry anchorage, use drilled-in expansion shields and hanger or lag bolts. For hollow masonry anchorage, use toggle bolts. For wood stud partitions, use hanger or lag bolts set into wood backing between studs. Coordinate with carpentry work to locate backing members. For steel-framed gypsum board assemblies, use hanger or lag bolts set into wood backing between studs. Coordinate with stud installation to locate backing members.
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7.
3.4
For steel-framed gypsum board assemblies, fasten brackets directly to steel framing or concealed steel reinforcements using self-tapping screws of size and type required to support structural loads.
ADJUSTING AND CLEANING A.
Touchup Painting: Immediately after erection, clean field welds, bolted connections, and abraded areas of shop paint, and paint exposed areas with the same material as used for shop painting to comply with SSPC-PA 1 for touching up shop-painted surfaces. 1.
Apply by brush or spray to provide a minimum 2.0-mil dry film thickness.
B.
Touchup Painting: Cleaning and touchup painting of field welds, bolted connections, and abraded areas of shop paint are specified in Division 09 painting Sections.
C.
Galvanized Surfaces: Clean field welds, bolted connections, and abraded areas and repair galvanizing to comply with ASTM A 780.
END OF SECTION 055100
METAL STAIRS
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