SECTION 05 5100 - METAL STAIRS PART 1

GENERAL

1.01 SECTION INCLUDES A.

Interior stairs with applied wood treads.

B.

Exterior Stairs

C.

Structural steel stair framing and supports.

D.

Handrails and guards.

1.02 RELATED REQUIREMENTS A.

Section 03 3000 - Cast-in-Place Concrete:

B.

Section 05 5000 - Metal Fabrications.

C.

Section 06 1000 - RoughCarpentry:

D.

Section 09 9000 - Painting and Coating:

Placement of metal anchors in concrete.

Blocking. Paint finish.

1.03 REFERENCE STANDARDS A.

ASTM A 6/A 6M - Standard Specification for General Requirements for Rolled Structural Steel Bars, Plates, Shapes, and Sheet Piling.

B.

AAMA 611 - Voluntary Specification for Anodized Architectural Aluminum; American Architectural Manufacturers Association.

C.

ASTM A 36/A 36M - Standard Specification for Carbon Structural Steel.

D.

ASTM A 53/A 53M - Standard Specification for Pipe, Steel, Black and Hot-Dipped, Zinc-Coated, Welded and Seamless.

E.

ASTM A 123/A 123M - Standard Specification for Zinc (Hot-Dip Galvanized) Coatings on Iron and Steel Products.

F.

ASTM A 153/A 153M - Standard Specification for Zinc Coating (Hot-Dip) on Iron and Steel Hardware.

G.

ASTM A 283/A 283M - Standard Specification for Low and Intermediate Tensile Strength Carbon Steel Plates.

H.

ASTM A 325 - Standard Specification for Structural Bolts, Steel, Heat Treated, 120/105 ksi Minimum Tensile Strength.

I.

ASTM A 325M - Standard Specification for Structural Bolts, Steel, Heat Treated 830 MPa Tensile Strength (Metric).

J.

ASTM A 500/A 500M - Standard Specification for Cold-Formed Welded and Seamless Carbon Steel Structural Tubing in Rounds and Shapes.

K.

ASTM A 501 - Standard Specification for Hot-Formed Welded and Seamless Carbon Steel Structural Tubing.

L.

ASTM E 985 - Standard Specification for Permanent Metal Railing Systems and Rails for Buildings.

M.

ATBCB ADAAG - Americans with Disabilities Act Accessibility Guidelines.

N.

AWS A2.4 - Standard Symbols for Welding, Brazing, and Nondestructive Examination; American Welding Society.

O.

AWS D1.1/D1.1M - Structural Welding Code - Steel; American Welding Society.

P.

NAAMM AMP 510 - Metal Stairs Manual; The National Association of Architectural Metal Manufacturers.

Q.

SSPC-Paint 15 - Steel Joist Shop Primer; Society for Protective Coatings.

R.

SSPC-Paint 20 - Zinc-Rich Primers (Type I, "Inorganic," and Type II, "Organic"); Society for Protective Coatings.

1.04 SUBMITTALS CHA 1427

05 5100 - 1

A.

See Section 01 3000 - Administrative Requirements, for submittal procedures.

B.

Shop Drawings: Indicate profiles, sizes, connection attachments, reinforcing, anchorage, size and type of fasteners, and accessories. 1. Indicate welded connections using standard AWS A2.4 welding symbols. Indicate net weld lengths. 2. Include the design engineer's stamp or seal on each sheet of shop drawings.

C.

Delegated Design Data:

As required by authorities having jurisdiction.

1.05 QUALITY ASSURANCE A.

The Fabricator shall have a minimum of 5 years experience in performing the Work of this Section. 1. The fabricator shall submit resumes showing compliance with the Work experience requirement to the A/E for written approval prior to starting the Work. 2. Prior to the start of Work, the fabricator shall submit certifications to the A/E and structural engineer for written approval, that they are registered and approved by the building official, in accordance with IBC Chapter 17. a. The fabricator shall be acceptable to the structural engineer and the architect

B.

The Erector shall each have a minimum of 5 years experience in performing the Work of this Section. 1. The Erector shall submit resumes showing compliance with the Work experience requirement to the A/E for written approval prior to starting the Work.

C.

The Contractor shall provide certification that welders employed in this Work have satisfactorily passed AWS qualification tests. 1. Fabricator(s) and erector(s) shall submit current welding certifications, for fabrication plant and field welding, to the A/E for written approval prior to the start of welding. 2. If re-certification of welders is required, retesting shall be the Contractor’s responsibility.

D.

Structural Designer Qualifications: Professional Structural Engineer experienced in design of this work and licensed in North Dakota, or personnel under direct supervision of such an engineer.

PART 2

PRODUCTS

2.01 METAL STAIRS - GENERAL A.

Metal Stairs: Provide stairs of the design specified and as indicate on the Drawings, complete with landing platforms, vertical and horizontal supports, railings, and guards, fabricated accurately for anchorage to each other and to building structure. 1. Regulatory Requirements: Provide stairs and railings complying with the most stringent requirements of local, state, and federal regulations; where requirements of the contract documents exceed those of regulations, comply with the contract documents. 2. Structural Design: Provide complete stair and railing assemblies complying with the following: a. Stair Capacity: Uniform live load of 100 lb/sq ft and a concentrated load of 300 lb with deflection of stringer or landing framing not to exceed 1/360 of span. b. Railing Assemblies: Comply with ASTM E 985. 3. At exit stairwells, provide unit stair towers designed for stacking to height of building as a self-supporting structure. 4. Dimensions: As indicated on drawings. 5. Shop assemble components; disassemble into largest practical sections suitable for transport and access to site. 6. No sharp or rough areas on exposed travel surfaces and surfaces accessible to touch. 7. Separate dissimilar metals using paint or permanent tape.

B.

Metal Jointing and Finish Quality Levels: 1. Architectural: All joints as inconspicuous as possible, whether welded or mechanical. a. Welded Joints: Continuously welded. b. Mechanical Joints: Butted tight, flush, and hairline; fasteners as determined with Architect. c. Exposed Edges and Corners: Eased to small uniform radius. d. Metal Surfaces to be Painted: Sanded or ground smooth, suitable for highest quality clear finish.

CHA 1427

05 5100 - 2

Grinding marks shall be visible after clear coat application. C.

Fasteners: Same material or compatible with materials being fastened; type consistent with design and specified quality level.

D.

Anchors and Related Components: Same material and finish as item to be anchored, except where specifically indicated otherwise; provide all anchors and fasteners required.

2.02 METAL STAIRS WITH CONCRETE TREADS A.

Interior Stair 1. Jointing and Finish Quality Level: Architectural as defined above. a. Risers: Closed. b. Treads: Metal with field-applied wood treads. 1) Tread Material: Steel sheet. 2) Tread Thickness: As required by design; 14 gage, 0.075 inch minimum. 3) Anchorage to Stringers: Welded or bolted to carrier angles welded or bolted to stringers. 2. Risers: Same material and thickness as tread pans. a. Riser/Nosing Profile: Sloped riser with rounded nosing of minimum radius. 1) Nosing Depth: Not more than 1 inch overhang. 2) Nosing Return: Flush with top of concrete fill, not more than 1/4 inch wide. (a) Detail to allow installation of wood treads and riser. b. Stringers: Rolled Steel Channels as detailed on the Drawings. 1) Stringer Depth: As indicated on drawings. 2) End Closure: Sheet steel of same thickness as risers welded across ends. c. Landings: Same construction as treads, supported and reinforced as required to achieve design load capacity. d. Railings: As indicated on the Drawings. e. Finish: Shop or factory-clear urethane finished. f. Under Side of Stair: Exposed to view, to be finished same as specified for other exposed to view surfaces.

B.

Exterior stair 1. Jointing and Finish Quality Level: Architectural as defined above. a. Risers: Closed. b. Treads: Metal pan. 2) Tread Material: Steel sheet. 3) Tread Thickness: As required by design; 14 gage, 0.075 inch minimum. 4) Anchorage to Stringers: Welded or bolted to carrier angles welded or bolted to stringers. c. Risers: Same material and thickness as tread pans. 1) Riser/Nosing Profile: Sloped riser with rounded nosing of minimum radius. 2) Nosing Depth: Not more than 1-1/2 inch overhang. 3) Nosing Return: Flush with top of concrete fill, not more than 1/2 inch wide. d. Stringers: Rolled Steel Channels and Rectangular Steel Tubing as Detailed on the Drawings. 1) Stringer Depth: 12 inches or as indicated on the Drawings. 2) End Closure: Sheet steel of same thickness as risers welded across ends. e. Landings: Same construction as treads, supported and reinforced as required to achieve design load capacity. f. Railings: Steel framework with steel mesh as shown on the Drawings and as specified herein. g. Finish: Clear Powder Coat. h. Under Side of Stair: Exposed to view, to be finished same as specified for other exposed to view surfaces.

2.03 HANDRAILS AND GUARDS A.

CHA 1427

Interior guard and handrail: 1. Stringer, as designed or as indicated on the Drawings. 2. Handrail supports a. Ferrous Handrails attached by bracket arm to metal pipe railings shall be attached by use of Wagner 1/2" R110 Bracket Arm with S101 Bracket Saddle or equal 05 5100 - 3

3. 4. 5.

6. B.

Top/Guard Rail: a. As indicated on the Drawings. Infill between end and intermediate supports: Steel Rod as indicated on the Drawings. End and Intermediate Posts: Steel Rod as indicated on the Drawings. a. Horizontal Spacing: As indicated on drawings. 48" Maximum. b. Mounting: Welded to face surface of stringer. Bar Infill: Steel Rod as indicated on the Drawings.

Exterior Railing and Mechanical Screen 1. Supports, Corner Post, Top Rails, Bottom Rails, as designed or as indicated on the Drawings. 2. Mesh Infill: McNichols, Steel, Woven Stock, 2 inch opening, .250 gauge.

2.04 MATERIALS A.

Steel Sections:

ASTM A 36/A 36M.

B.

Steel Tubing:

D.

Steel Plates:

E.

Pipe:

G.

Ungalvanized Steel Sheet: Hot- or cold-rolled, except use cold-rolled where finished work will be exposed to view. 1. Hot-Rolled Steel Sheet: ASTM A 1011/A 1011M, Designation CS (commercial steel). 2. Cold-Rolled Steel Sheet: ASTM A 1008/A 1008M, Designation CS (commercial steel).

I.

Steel Bolts, Nuts, and Washers: ASTM A 325 (ASTM A 325M), Type 1, galvanized to ASTM A 153/A 153M where connecting galvanized components.

J.

Welding Materials:

ASTM A 500 or ASTM A 501 structural tubing, round and shapes as indicated. ASTM A 6/A 6M or ASTM A 283/A 283M.

ASTM A 53/A 53M, Grade B Schedule 40, black finish.

AWS D1.1; type required for materials being welded.

2.06 SHOP FINISHING A.

Clean surfaces of rust, scale, grease, and foreign matter prior to finishing.

B.

Do not prime surfaces.

2.07 FINISHES A.

Prepare surfaces by removing mill oils by washing with solvents

B.

Clean surfaces of rust, scale, grease, and foreign matter prior to finishing.

C.

Interior Finish:

Satin Polyurethane.

C.

Exerior Finish:

Clear Powdercoat.

PART 3

EXECUTION

3.01 EXAMINATION A.

Verify that field conditions are acceptable and are ready to receive work.

3.02 PREPARATION A.

When field welding is required, clean and strip primed steel items to bare metal.

B.

Supply items required to be cast into concrete and embedded in masonry with setting templates.

3.03 INSTALLATION A.

Install components plumb and level, accurately fitted, free from distortion or defects.

B.

Provide anchors, plates, angles, hangers, and struts required for connecting stairs to structure.

C.

Allow for erection loads, and for sufficient temporary bracing to maintain true alignment until completion of

CHA 1427

05 5100 - 4

erection and installation of permanent attachments. D.

Provide welded field joints where specifically indicated on drawings. AWS D1.1.

Perform field welding in accordance with

E.

Other field joints may be either welded or bolted provided the result complies with the limitations specified for jointing quality levels.

F.

Obtain approval prior to site cutting or creating adjustments not scheduled.

G.

After erection, prime welds, abrasions, and surfaces not shop primed or galvanized, except surfaces to be in contact with concrete.

3.04 TOLERANCES A.

Maximum Variation From Plumb:

1/4 inch per story, non-cumulative.

B.

Maximum Offset From True Alignment:

1/4 inch.

END OF SECTION

CHA 1427

05 5100 - 5