What is meant by the term "composite floor decking," and how exactly does it work?

What is meant by the term "composite floor decking," and how exactly does it work?

At the time of planning a single-story or multi-story building, several components are kept in consideration. Starting from the walls, frame, roof, floor, and more, there are many factors that an engineer has to take care of. Out of these major components, the metal deck floor system is also one. But still, not every design option is the best.

Priority of the choices to make the floor more vital includes adding extra weight. This can impact other things in the building, like the steel framing. Composite metal floor deck systems have been designed to solve this specific issue. The most crucial benefit of composite metal floor decks is the floor system's strength without the need to add extra weight. 

You can get the composite metal floor deck in various profiles, lengths, and gauges. Each of these profile type and gauge is engineered for specific concrete slabs and yield different strength values. Every project is engineered differently. Some areas need higher strength, a heavier gauge, or a different profile type. 

What is composite floor decking?

The composite metal floor deck consists of a metal floor deck that has an embossment pattern manufactured into the sides at equal intervals. The embossing helps the concrete bond to the metal deck panel as the concrete cures. The most crucial difference between the roof and floor deck is that the roof deck does not have embossment.

Types of composite floor decking 

Types of composite floor decking


The wooden deck is comparatively less expensive, but these need frequent maintenance and repair. The cleaning method in this also varies with wood decking.


Plastic decking is more expensive than wood decking, but they give longer service life and need fewer maintenance services. This deck may appear artificial, and it may also expand or contract due to the temperature change. 


Metal floor decking is even more expensive than wooden or plastic decking but provides more benefits than both. The steel deck is the sort of flooring deck built of CD formed, corrugated sheets and joints supporting it, which are well-suited for the industries. 

After the concrete cures, the metal deck and concrete become one item and bond together. They finally become composite metal floor decks. This composite metal floor deck has much more strength than the two individually summed together. Some of these deck profiles have embossments that are designed such that they can be used with concrete slabs.


The composite floor deck is more expensive than wood but less expensive than metal or plastic decking. These also need less maintenance. The embossment pattern manufactured on the panel is referred to by various names, which depend on the decking manufacturer. 

Different types of metal floor deck

Different types of metal floor deck

You can find many options when looking for composite metal floor decking boards. These are made of different profiles, and each of these offers different strength values. There are three kinds of depths of FormLok composite metal decks. 

  • 1½” composite metal deck type B-36 FormLok
  • 2” composite metal decks type W2-36 FormLok
  • 3” composite metal deck type W3-36 FormLok

Side lap types of composite metal floor deck

Side lap types of composite metal floor deck

Two different kinds of side laps can do the manufacturing of composite metal floor decking boards. It can be manufactured with the screw-fastened side lap or the standard interlocking side lap.

The most used standard side lap connection type specified on the composite floor deck is the standard interlocking side lap. It helps the side laps connect by the button punch, top seam weld, or the PunchLok. This will be specified when the project planning is done to see which side lap is required.

Benefits of composite metal floor decking 

  • There are some essential benefits of using composite metal floor decks. The top one is the added strength. This strength is given by the addition of FormLok embossment, which helps it bond with the metal decking panel when the concrete cures. 
  • The second pro of using composite metal floor decking boards is that the FormLok embossment does not add extra weight. If you compare the weight of both the embossment and non-embossment panels, their weight would be identical. But if you still add extra weight to it, you will need to account for that in several areas. This makes the embossment panels more valuable when one wants to straighten the floor system.
  • The pricing can be another benefit of choosing FormLok decking. The addition of FormLok is $1 per 100 square feet or 1c per square foot. Hence, the FormLok embossment is a great way to strengthen the composite floor deck slab at affordable rates.

Bottom line

Now you should have understood what composite floor decks and their types are. There are several types of profiles of composite floor decking, each being unique. Some may need less maintenance, and some may be cost-effective. All these are compared, and the right one is chosen when a single-story or multi-story building is constructed.