053150MSBA Accelerated Repair Program RK Finn/Ryan Road and Leeds Elementary Schools Northampton, Massachusetts
Steel Deck Infill
05 31 50-1
SECTION 05 31 50
STEEL DECK INFILL
PART 1 - GENERAL
1.01 SECTION INCLUDES:
A. If, during the construction, it is determined that deteriorated steel decking exists, the
Contractor shall inspect, replace, or plate over the steel deck that is rusted or
deteriorated, as directed by the Owner's Representative. See Section 01 27 00
Unit Prices.
B. Make steel deck repairs or replacement on a unit price basis (except as
indicated in the base bid quantities.
C. All deteriorated areas of steel deck shall be removed and replaced or plated over.
The Contractor is to exercise extreme caution when removing existing roofing
systems to ensure the integrity of the existing roof deck. Any additional roof deck
damage as a result of the roof removal process shall be properly repaired by the
Contractor, as specified herein, at no additional cost to the Owner,
D. The Contractor shall notify the Owner's Representative immediately upon
uncovering existing steel deck showing signs of deterioration or excessive
deflection. All deck replacement areas must be photographed and marked on a
separate roof plan dedicated for deck repair tracking.
E. At locations where obsolete units are removed, 18 gauge galvanized plate can be
used for openings up to 18." Larger openings shall be repaired using new steel deck
spanning at least two supports. Existing deck shall be matched in profile and gauge.
F. Maintain steel deck and steel plate on the jobsite. Do not start work without
replacement deck and plate on site.
G. All deck replacement includes removal and re-installation of any systems
attached to the underside of the deck, including, but not limited to, electrical wires,
conduit, HVAC lines, hangars, or other items.
H. The drawings indicate and show limits of construction for this project. The
specifications specify materials and work requirements for this project. Both are
complementary to each other and shall be followed to complete the work.
1.02 RELATED WORK
A. Section 01 27 00 Unit Prices
B. Section 02 41 19 Selective demolition
C. Section 06 10 00 Rough Carpentry
D. Section 07 53 23 Roofing
MSBA Accelerated Repair Program RK Finn/Ryan Road and Leeds Elementary Schools Northampton, Massachusetts
Steel Deck Infill
05 31 50-2
1.03 SUBMITTALS
A. Submit copies of product data and specified number of and samples as
listed below.
1. Manufacturer's literature of each type of fastener usedfor steel deck
repair identified with brand type, size, finish, and other descriptive
information.
2. Manufacturer's literature and data sheets on steel deck, if
requested.
3. Manufacturer's literature and data sheets on primer for galvanized
and painted steel deck or plates.
1.04 UNIT PRICES
A. The Contractor shall carry the assigned quantities of replacement or repair
(listed below) in the Base Bid. Add/Deduct unit pricing has been assigned for
this work.
1. Random removal and replacement of existing rusted or deteriorated
steel deck on all roof levels, except at concrete deck or plank areas
including fastening. This quantity is for installation over and above
the work associated with removal of obsolete equipment and
related service connections. Quantities shall be determined by
calculation of actual square footage installed with no allowance for
waste.
a. See Section 01 27 00 Unit Prices
2. Random installation of 18 gauge galvanized plate over openings less
than 18," including fastening. This quantity is for installation over
and above the work associated with removal of obsolete equipment
and related service connections. Quantities shall be determined by
calculation of actual square footage installed with no allowance for
waste.
a. See Section 01 27 00 Unit Prices
PART 2 - PRODUCTS
2.01 STEEL MATERIALS
A. Coordinate the structural Diaphragm loading splice that will be required,
if the decking will not nest properly, to transfer the lateral loads with the
MSBA Accelerated Repair Program RK Finn/Ryan Road and Leeds Elementary Schools Northampton, Massachusetts
Steel Deck Infill
05 31 50-3
details provided by the Structural Engineer of Record.
B. Steel deck shall match existing deck as to gauge and profile, except
gauge of replacement material may be greater (thicker) than existing. If
profile cannot be matched, utilize Type "B" deck with the same height
profile as existing.
C. Galvanized steel decks shall be 20 gauge.
D. Galvanized steel sheet for removal of obsolete equipment openings
shall be 18 gauge, 18" or less.
2.02 FASTENERS
A. Sidelap or Sheet Steel Fasteners: For new or existing steel deck shall be #12 x 3/4" zinc-plated hex-washer head self-drilling sheet metal screws.
B. Endlap Fasteners: For new or existing steel deck, with standard "nesting"
ability, shall be #14 x 1-1/4" zinc-plated hex-washer head self-drilling sheet
metal screw designed for fastening to structural steel.
PART 3 - EXECUTION
3.01 STEEL DECK REPLACEMENT
A. Sections of existing steel deck to be replaced shall be cut square and neat.
Cut ends of deck at bearing supports. Cut ends will provide sufficient
bearing distance as required by the SDI (Steel Deck Institute). Contractor
shall note the location of all conduit, light supports, etc., prior to removal
of existing deteriorated steel deck.
B. New sections of steel deck shall span at least two (2) supports.
C. Fasten deck, as specified.
D. Where deck replacement is specified at a roof drain, coordinate with roof
drainage requirements, as specified.
1. Nest new decking to the existing by using the SDI details.
2. After decking is secured, cut to receive the drain sump pan, being
careful not to oversize the cut. Cutting shall be done with a portable,
hand-held, reciprocating jig saw provided with a sharp blade. No
burning will be permitted.
3. Install the sump pan using than 12 fasteners located three (3) to
each side.
3.02 FASTENING OF NEW OR EXISTING STEEL DECK
MSBA Accelerated Repair Program RK Finn/Ryan Road and Leeds Elementary Schools Northampton, Massachusetts
Steel Deck Infill
05 31 50-4
A. Verify all recommendations with the Structural Engineer of Record and
obtain written approval prior to the start of work.
B. Sidelaps and endlaps of existing steel shall be fastened when existing welds
or other fastenings are broken or insufficient according to the decision of the
Owner's Representative.
C. Endlap fasteners shall be installed at 6" o.c. (on center) on all bearing points.
The deck shall be pulled down snugly onto the the bearing joist or beam.
D. Sidelap fasteners shall be installed at the mid-points of all spans exceeding
3" and at the third points of all spans exceeding 6." Sidelap fastener spacing
shall not exceed 3'-0" o.c. Mating surfaces shall be pulled snug.
3.03 INSTALLATION OF STEEL PLATE
A. Verify all recommendations with the SDI requirements.
B. Sheet steel shall lap the area requiring reinforcement by a minimum of
12" in all directions.
C. Fasten steel sheet at 6" o.c. at the perimeter and 12" o.c. in the field of
the sheet.
3.04 NESTING OF STEEL DECK CONNECTIONS
A. When steel decks are replaced, the new steel deck shall nest into the
adjacent existing decking at the end and side laps, as required by SDI
written requirements.
B. The Contractor shall make every effort to obtain new structural steel
decking that matches the existing structural steel decking in profile and
gauge. If the gauge cannot be matched, then decking with thicker
gauge will be acceptable. If new structural steel decking of the same
profile as the existing structural decking cannot be obtained, then the
Contractor shall fabricate and install splice plates. The splice plates
and fasteners must be approved, in writing, by a Structural Engineer
hired by the roofing contractors if this condition is encountered. The
Structural Engineer of Record will certify that the connections and
splice plates will transfer all lateral diaphragm and gravity loads required
by the Massachusetts State Building Code for this building.
END OF SECTION 05 31 50