N deck roof deck spans large spaces economically

B Deck

Perfect balance of strength, economy and versatility

B Deck
Type B deck is a wide-rib roof deck ideal for a wide range of applications

Type B, wide-rib structural roof deck is a high-performance, cost-efficient choice with a variety of options to meet multiple project needs. Standard or cellular, acoustic or vented, interlocking or nested side laps, B deck is among the most flexible of our 1½-inch deep roof decks.

Standard B Deck

Type B roof deck provides the best balance of strength and economy of all the 1½-inch-deep roof decks. Where rigid roofing insulation is used with B deck, a minimum 1-inch thickness is required.

B deck is available in lengths from 6’-0” to 40’-0”. Please check with your local New Millennium facility for lengths outside these parameters. Conforms to ASTM A1008/A1008M for uncoated and painted deck, A653/A653M for galvanized deck. Approved by UL, ULC and listed in the UL and ULC Fire Resistance Directories.

Yield strength up to 80ksi. Refer to published tables for the minimum yield strength used for each deck type. Contact New Millennium for availability of higher yield strengths when required or use our deck specification tool to view load tables with commonly available non-standard yield strengths and/or gages.

Standard B Deck
Standard B Deck Drawing
Standard B Deck Dimensions
Standard B Deck Acoustical
Standard B Deck Acoustical Drawing
Standard B Deck Acoustical Dimensions
Standard B Deck Vented
Standard B Deck Vented Drawing
Standard B Deck Vented Dimensions
  • Types B, B-Dek, BV, BV-Dek, BA and BA-Dek available with nested side laps. Types BI, BIV and BIA available with interlocking side laps
  • Available as an acoustic deck, types BA, BA-Dek and BIA are manufactured with perforations in the vertical ribs, having an NRC rating of 0.50 to 0.95 when used with rigid insulation, as tested in accordance with ANSI/ASTM C423 and E795
  • Available as a vented deck, types BV, BV-Dek and BIV are manufactured with slot vents in the bottom flutes (to be specified when venting is required for cementitious insulation fill). The openings for types BV and BIV can be specified from 0.5% up to 1.5% of total surface. The openings for BV-Dek can be specified from 0.25% up to 2.0% of total surface
  • Also available with rolled-in hanger tabs (non-vented types only)
  • Type B roof deck is FM-approved for use as a component in Classes 1-60, 1-75 and 1-90 wind uplift construction. When ratings above 1-90 are required, the Contract Documents must specify special requirements in accordance with FM Data Sheet 1-29, Section 2.2.13
  • Types B, BI and B-Dek are ICC-, FM- and UL-approved
Cellular B Deck

B-Dek Cellular is a 1½-inch-deep cellular structural roof deck that provides a support surface for various types of roofing materials. The liner panel with the Dek-Knek® Side Lap Attachment System provides a finished underside ceiling with self-aligning side laps and concealed fasteners. B-Dek Cellular Acoustical features a perforated liner panel, providing an NRC of 0.70 when used with a rigid insulation. Fiberglass acoustic batts are installed in the B-Dek Cellular Acoustical cells at the factory under controlled conditions.

B-Dek Cellular
B-Dek Cellular Drawing
B-Dek Cellular Dimensions
B-Dek Cellular Acoustical
  • Available in 24½-inch cover width
  • Available in seven steel gage thicknesses (see load tables) link to load tables page with various deck/liner panel thicknesses, a variety of galvanized coating weights and an array of paint systems
  • Used as a secondary structural member to provide for lateral force distribution to the structure’s vertical force resisting system
  • B-Dek Cellular Acoustical available with optional plastic lath to protect the acoustical properties of the deck when painting in the field
  • Types B-Dek Cellular and B-Dek Cellular Acoustical are ICC-approved
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Case Study
Tualatin Hills Aquatic Center in Beaverton, Oregon,
Creativity solves problem roof

Natatorium’s new roof uses inverted B deck to provide economical acoustical control and aesthetics.

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