Type A Roof Deck, also known as narrow rib deck, provides a wide support surface for various types of rigid insulation and roofing materials. This structural metal Type A decking is 1-1/2” deep and 36” wide. It transfers horizontal and vertical loads into the building frame. Additionally, Type A Roof Deck comes with a primer painted finish in stock lengths of 20’–2”and custom lengths.
History of Type A Decking
When engineers developed type A roof decking and type F roof decking, they focused on the strength of the metal deck. However, it was only a secondary of concern. The primary objective was to maximize the width of the top flange. This would provide the maximum amount of support for the roofing insulation installed on top of the Type A decking. Over time, roofing materials improved and steel deck manufacturers were able to reduce the width of the top flange. This reduction increased the efficiency of the section from Type A decking to Type F decking. And finally, from Type F deck to Type B deck.
Replacing Type A roof deck in a repair or re-roof application may present some challenges compared to replacing Type B deck. Since the existing narrow rib deck may have a stiffening rib in the top flange, the supports may be spaced farther apart than “modern” Type A decking can span at the same gauge.
Purpose for Type A Roof Deck
Type A roof deck usually serves as patch material for reroofing projects since more economical types of roof deck are now available.
Low maintenance and high strength, type A decking is designed for low-pitched or flat construction. Use Type A roof deck on virtually all types of nonresidential buildings: schools, arenas, malls, supermarkets, auditoriums, and similar structures.
Purchase Type A Decking at Keystar
Keystar Industries Type A roof deck products meet the required steel deck certifications in accordance with the specifications of the Steel Deck Institute. The material thickness of Type A decking stocked by Keystar is 20 gauge.
Furthermore, Keystar Industries stocks Type A roof deck, narrow rib, in a variety of lengths with a prime painted finish. Keystar’s steel Type A decking products are an economical and convenient choice for any construction roofing or reroofing project.
The most economical finish for type A roof deck is prime painted grey over bare steel. Typically, this finish provides adequate temporary protection to the base metal of the Type A decking during construction.
Unlike other deck types, type A roof deck is rarely used for new construction projects. Rather, use it for repairs and re-roof projects. This is due to the fact that it is the least efficient 1.5” deep steel roof deck type. Compared to Type B deck and Type F roof decks, Type A deck has the lowest strength-to-weight ratio. As with all steel products, the lighter the section, the more economical. Since A steel deck cannot carry as much load at longer spans as B deck and F deck, the steel supports below the metal deck must be spaced closer together. A smaller support spacing results in more supports and higher construction costs with Type A decking.
Keystar, the metal deck supplier
Keystar Industries carries metal deck products in a variety of depths, widths, gauges, and finishes. Deck products include roof deck, composite deck, and form deck. Galvanized or primed finishes provide long-lasting, corrosion resistant decking for roofing and flooring requirements in the construction industry. Additionally, Keystar stocks metal decking that meets required steel deck certification in accordance with the Steel Deck Institute’s (SDI) specification.
Whether the need is immediate for a piece of metal deck to patch a rusted area on a roof, or for a variety of deck types for a new office tower, Keystar can satisfy with immediate service, high quality products, and professionalism. Pick up your product at the warehouse in Eagan, MN, or Keystar will coordinate shipping to your job-site.
See Keystar’s offerings of A deck metal deck with a prime painted finish for your roofing solutions. Call 651.256.0008 or email [email protected] for pricing and availability.