Fields BUR Systems Design Criteria Roof Decks

Attachment of Steel Panels to Roof Framing Supports: Steel deck panels shall be attached to the roof’s framing supports by welding. Spacing of attachment points shall be no more than 12 on center to minimize deck rolling and movement under the concentrated moving of rooftop loads. Deficient welds shall be replaced before installing the roof system. Additional roof deck supports shall be installed as required at roof perimeters and penetrations.

Steel deck panels shall be installed in a straight line, and shall be correctly aligned, squarely intersecting walls and the building framing system in order to facilitate the correct installation of the rigid insulation boards. The horizontal variance in the alignment of the panels shall not exceed .25 for every 100 feet of roof panel length.

Attachment of Steel Side Laps: All side laps shall be mechanically fastened. Fastener spacing shall not exceed 3′. If an interlocking deck is installed, fastening may be accomplished by crimping the interlock with a button punch. Fastening through overlapping steel deck panels requires the use of number 8 or larger self tapping screws.

Rigid Boards Fastened to Top Flange of Steel Panels: Rigid insulation or rigid boards shall meet ASTM C 36 or C 1178 for horizontal installations. Such overlayment shall be mechanically fastened through the top flange of the steel deck panels. Rigid boards shall be mechanically fastened to steel roof decks according to the steel deck manufacturer’s recommendations.

Holes in Steel Deck: When a hole is cut to accommodate a penetration through a steel panel, supplemental framing is required to support the opening. The required support depends upon the steel deck gauge, rib spacing, span, and size of the opening. Designers shall follow the guidelines set forth in the Steel Deck Institute’s publication, Deck Damage and Penetrations.

Illustration 4: Steel deck reinforcing for openings.

Insulation installed directly over steel decks shall have the strength to support anticipated roof deck loads. Required minimum insulation thickness varies, depending on the strength of the insulation board and the rib width opening of the steel deck panels. The insulation manufacturer shall be consulted for insulation strength per thickness.

Wind Uplift: Steel roof decks shall be designed and installed with adequate attachment to the framing support system so as to prevent wind uplift per local wind uplift codes.

High Humidity Buildings and Vapor Retarders: If the building is expected to have a high relative humidity that contributes to corrosion of the steel deck, the deck manufacturer shall be consulted for specific steel coating and protection requirements. At a minimum, designers shall specify factory galvanized G-90; or aluminum zinc alloy coated steel decks for corrosion protection. If the metal deck is to receive a structural or lightweight insulating concrete topping, a aluminum zinc alloy coating is prohibited.

Vapor retarders for steel decks shall be installed over a layer of rigid insulation or water resistant exterior type rigid boards.

Steel Deck Preparation: Steel decks shall be correctly attached and deck surfaces shall be clean and free of upturned edges, sharp burrs and contaminants that may affect the correct installation of the Fields roof system.

Weather and Temperature: Factory painted steel roof deck panels shall be delivered with a minimum primer paint coating. Painted or primed steel deck panels exposed to the weather may rust at areas where the paint or primer coating has been damaged, and at edges that have been cut. Prolonged exposure to the weather may affect the integrity of the steel panels.

Installation of the steel roof deck shall be scheduled and coordinated with weather and temperature conditions that allow for the correct installation of the roof system. If unprotected panels are damaged or deteriorated from weather exposure, they shall be replaced prior to installation of the Fields roof system.

Suspended Ceilings: Steel roof decking is not intended to support suspended ceilings and interior fixtures. Excessive roof deck deflection may be attributed to improperly suspended ceiling loads. Special hangers shall be installed from the framing system to suspend ceilings and interior fixtures.

Insulation Board Attachment: The first layer of insulation or rigid boards shall have the strength to span the rib openings of the steel panels as well as support anticipated loads, and shall be fastened to the steel deck with mechanical fasteners. The edges of the rigid insulation or rigid boards shall not cantilever over the rib openings of the steel deck. The second layer, which shall be only rigid insulation boards shall be adhered with the specified Fields asphalt to the first layer of rigid insulation or rigid boards or to a Fields vapor retarder installed on top of a first layer of rigid insulation or rigid boards.

When conditions are such that installing the insulation in more than one layer becomes impractical, a single layer of insulation shall be mechanically fastened to the steel roof deck. When the rigid insulation or rigid boards are installed in a single layer, they shall be well supported by the top flange of the steel deck or by a mechanically fastened steel plate.

Attachment of Steel Panels to Roof Framing Supports: Steel deck panels shall be attached to the roof’s framing supports by welding. Spacing of attachment points shall be no more than 12 on center to minimize deck rolling and movement under the concentrated moving of rooftop loads. Deficient welds shall be replaced before installing the roof system. Additional roof deck supports shall be installed as required at roof perimeters and penetrations.

Steel deck panels shall be installed in a straight line, and shall be correctly aligned, squarely intersecting walls and the building framing system in order to facilitate the correct installation of the rigid insulation boards. The horizontal variance in the alignment of the panels shall not exceed .25 for every 100 feet of roof panel length.

Attachment of Steel Side Laps: All side laps shall be mechanically fastened. Fastener spacing shall not exceed 3′. If an interlocking deck is installed, fastening may be accomplished by crimping the interlock with a button punch. Fastening through overlapping steel deck panels requires the use of number 8 or larger self tapping screws.

Rigid Boards Fastened to Top Flange of Steel Panels: Rigid insulation or rigid boards shall meet ASTM C 36 or C 1178 for horizontal installations. Such overlayment shall be mechanically fastened through the top flange of the steel deck panels. Rigid boards shall be mechanically fastened to steel roof decks according to the steel deck manufacturer’s recommendations.

Holes in Steel Deck: When a hole is cut to accommodate a penetration through a steel panel, supplemental framing is required to support the opening. The required support depends upon the steel deck gauge, rib spacing, span, and size of the opening. Designers shall follow the guidelines set forth in the Steel Deck Institute’s publication, Deck Damage and Penetrations.

Illustration 4: Steel deck reinforcing for openings.

Insulation installed directly over steel decks shall have the strength to support anticipated roof deck loads. Required minimum insulation thickness varies, depending on the strength of the insulation board and the rib width opening of the steel deck panels. The insulation manufacturer shall be consulted for insulation strength per thickness.

Wind Uplift: Steel roof decks shall be designed and installed with adequate attachment to the framing support system so as to prevent wind uplift per local wind uplift codes.

High Humidity Buildings and Vapor Retarders: If the building is expected to have a high relative humidity that contributes to corrosion of the steel deck, the deck manufacturer shall be consulted for specific steel coating and protection requirements. At a minimum, designers shall specify factory galvanized G-90; or aluminum zinc alloy coated steel decks for corrosion protection. If the metal deck is to receive a structural or lightweight insulating concrete topping, a aluminum zinc alloy coating is prohibited.

Vapor retarders for steel decks shall be installed over a layer of rigid insulation or water resistant exterior type rigid boards.

Steel Deck Preparation: Steel decks shall be correctly attached and deck surfaces shall be clean and free of upturned edges, sharp burrs and contaminants that may affect the correct installation of the Fields roof system.

Weather and Temperature: Factory painted steel roof deck panels shall be delivered with a minimum primer paint coating. Painted or primed steel deck panels exposed to the weather may rust at areas where the paint or primer coating has been damaged, and at edges that have been cut. Prolonged exposure to the weather may affect the integrity of the steel panels.

Installation of the steel roof deck shall be scheduled and coordinated with weather and temperature conditions that allow for the correct installation of the roof system. If unprotected panels are damaged or deteriorated from weather exposure, they shall be replaced prior to installation of the Fields roof system.

Suspended Ceilings: Steel roof decking is not intended to support suspended ceilings and interior fixtures. Excessive roof deck deflection may be attributed to improperly suspended ceiling loads. Special hangers shall be installed from the framing system to suspend ceilings and interior fixtures.

Insulation Board Attachment: The first layer of insulation or rigid boards shall have the strength to span the rib openings of the steel panels as well as support anticipated loads, and shall be fastened to the steel deck with mechanical fasteners. The edges of the rigid insulation or rigid boards shall not cantilever over the rib openings of the steel deck. The second layer, which shall be only rigid insulation boards shall be adhered with the specified Fields asphalt to the first layer of rigid insulation or rigid boards or to a Fields vapor retarder installed on top of a first layer of rigid insulation or rigid boards.

When conditions are such that installing the insulation in more than one layer becomes impractical, a single layer of insulation shall be mechanically fastened to the steel roof deck. When the rigid insulation or rigid boards are installed in a single layer, they shall be well supported by the top flange of the steel deck or by a mechanically fastened steel plate.


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