Steel decking is the ideal option for providing structural support on your commercial building projects. Given the wide selection of metal decking that is available, it can be difficult to decide which product will perform the best — let alone what the associated costs may be.
The good news is that our experts at O’Donnell Metal Deck can help. We created this detailed guide to help give you more perspective on metal deck materials and their costs — it covers the types of metal decks available, as well as their gauges and finishes, and the external factors affecting cost including job size and delivery charges. Let’s dive in!
Factors that Impact the Cost of Metal Decking
The Cost of Steel
The cost of steel is subject to multiple influences like the availability and expense of raw materials, energy costs, supply versus demand, rivalry in the market, transportation charges and production expenses. However, the most significant factor that affects metal deck’s price tag lies primarily with steel itself due to its reliance on components such as iron ore, coal and limestone which are necessary for its fabrication. As expected, most commodities prices veer off course often — making it difficult to predict the exact amount you will pay at any given moment in time.
Typically, the price ranges from $3.00 to $7.00 per square foot for metal deck materials. However, fluctuations in steel prices will affect these numbers and possibly render them invalid after 30 days. That’s why it is essential to have your quotes updated regularly.
The Gauge of the Metal
Steel thickness, also known as a gauge (ga.), influences the cost of metal decking. The standard gauges are 22, 20, 18 and 16. Thinner gauges are more expensive than thicker ones because they require less steel material for construction.
As a rule of thumb, smaller numbers indicate greater thickness, so 16 ga. is thicker than 18 ga., while 18 ga. surpasses 20 ga. in terms of durability and strength alike.
The Type of Metal Deck
Different types of metal decking will require different amounts of steel, affecting the cost. Let’s break down the three types of metal decks and their common sizes and profiles.
Types of Metal Deck
Metal Roof Deck
Metal roof decking is crafted to supply a strong, dependable foundation for your entire rooftop structure. It can be easily installed on top of trusses, open web joists or beams and extend in between them to form an excellent base layer that the other parts of the system can rest upon. A metal roof deck is only one element of a complete roof system.
To ensure stability, the metal roof deck is designed to support two types of loads: dead and live.
The first one refers to roofs made out of rigid board insulation and built-up materials that make up the entirety of a rooftop system’s weight.
The latter represents any extra load created by construction workers or equipment during installation.
In addition, this type of decking also creates horizontal diaphragm shear for increased protection against natural disasters such as high winds, storms and earthquakes.
B Roof Deck (Wide Rib)
B Deck is the most widely used structural metal decking in the construction industry due to its powerful yet lightweight, cost-effective and effortless installation.
With a panel depth of 1.5 inches and width of 36 inches, B Deck offers superior performance on short and medium-span conditions ranging from 3 feet up to 10 feet apart.
N Roof Deck (Deep Rib)
Type N roof deck is your solution for longer spans, ranging from 6 to 16 feet. This 3-inch deep panel comes in two varieties: 24-inch (N-24) or 32-inch wide panels (HSN3-32).
If you have a project that requires extra support and extended reach, then Type N roof deck panels may be your solution.
Metal Form Deck
Form deck, a corrugated metal sheeting used as a concrete form, is an economical and effective solution for structural building. It offers several advantages. It doesn’t need to be removed once the slab has been poured as wooden forms do, and in some cases, it eliminates the need for expensive shoring. However, unlike composite decking, steel form deck does not add strength to the floor system itself.
Metal form deck isn’t manufactured with embossments, which is the component that allows the concrete to bond with the metal. It is only a form to support the weight of the concrete.
9/16-Inch Steel Form Deck
If you’re looking for a lightweight but dependable form deck that spans shorter distances, a 9/16-inch steel form deck is your best bet.
This type of form decking offers exceptional strength and stability to structural components while still being perfect for small spans and residential applications.
1-Inch Steel Form Deck
For concrete applications that require a permanent base to support slabs, a 1-inch steel form deck is the perfect solution. Recommended for 2 inches of poured concrete over its depth, this type of decking will provide stable spans from one foot up to eleven feet depending on the gauge used.
Composite Steel Deck
Composite metal floor decking provides distinct advantages over form decking due to its unique embossment pattern that is incorporated into the side flutes.
This pattern creates a strong connection between concrete and steel and results in an even more solid bond as it cures.
As opposed to roof decks, which lack this feature, composite metal floor decks offer unparalleled strength for your project’s needs. By the end of the concrete curing process, the metal decking and concrete become inseparably united to form a composite metal floor deck that is stronger than the individual components. Composite metal decking is offered in 16, 18, 20, and 22 ga.
1.5-Inch Composite Steel Deck
With 1.5-inch composite metal decking, you will require less concrete, but it can only span shorter distances than its deeper counterparts. To ensure the best results, a minimum of 2 inches of concrete should be poured over the ribs to form a total slab thickness of 3.5 inches.
This type of floor deck is ideal for multiple-story buildings and structures such as mezzanines, bridge walkways, porches, in-fills platforms and parking garages or storage facilities. Featuring a ribbed design and embossments specifically crafted to interlock with concrete, this reinforced slab offers the advantages of both permanent formwork and positive reinforcement.
2-Inch Composite Steel Deck
With its 2-inch deep ribs, the 2-inch composite metal decking creates sufficient space for reinforcing materials such as rebar or wire mesh. This allows it to span greater distances. To ensure maximum strength and stability of your structure, we recommend 4 inches total slab thickness by pouring at least 2 inches of concrete over the deck’s ribs.
3-Inch Composite Steel Deck
For lasting durability and strength, composite metal decking with a 3-inch thickness is the ideal choice. This deck requires extra concrete coverage but spans greater distances than shallower options. To ensure quality construction, it’s recommended that at least 2 inches are poured over the ribs for an overall slab thickness of 5 inches.
Metal Deck Finishes
Certain finishes can be more costly than others, which can affect the overall cost of your metal deck.
G-60 is the most popular hot-dip galvanizing finish that provides .6 oz of zinc per square foot. Metal decking constitutes 90 percent of all projects that require galvanization, a process designed to enhance the lifespan and durability against corrosion. G-60 offers superior protection for your steel or iron structures to extend serviceability over years to come!
G-90 galvanized metal decking provides a full .9 oz of zinc weight per square foot and is especially suitable for coastal or highly corrosive projects. Because of its higher cost, G-90-grade material is rarely specified for construction jobs.
PTD or primer-painted metal decking is an impermanent, provisional coating that usually comes in a gray finish. It’s mostly used for applications where the material will not be exposed to the elements because it may rust if left unprotected. The benefit of this type of metal decking lies mainly in its cost-effectiveness — you can save up to 10 cents per square foot! However, take note that without proper protection from weather damage, PTD panels are at risk of acquiring unsightly red rust stains on both sides.
Price is always affected by the size of the job and larger jobs will usually receive the lowest cost per sheet.
Custom cutting and factoring in waste can contribute to the final cost, but here at O’Donnell Metal Deck, we have various gauges of metal decking stocked for each type in varying lengths every few feet in order to reduce wasteful spending.
If your job necessitates sheets that are a few inches or even a few feet shorter than our stock length options available, then we will be able to accommodate your request at an additional charge, so you should plan accordingly beforehand when budgeting.
Shipping and Delivery
Generally, metal decking quotes are provided as will-call orders. If you don’t have the means to get your order from the vendor’s location yourself, be sure to ask about delivery services — most companies offer this service for an additional charge.
Find the Best Metal Decking Options with O’Donnell Metal Deck
For more than three decades, we have been dedicated to providing exceptional quality metal deck and floor products with reliable national distribution. As a proud testament to our success, over 15,000 projects have used our top-notch materials for their construction needs.
From private developers to contractors and even government agencies or institutions — no matter the project size or type — our team of professionals offers an unbeatable combination of excellent product knowledge, fast delivery times and professional support every step along the way.
Contact us today and let us assist you with your next project!