Can Type B Metal Deck Be Used With Concrete in Florida?
Type B is a roof deck, not a composite deck. It works with cementitious insulation and lightweight insulating fill, ideally in its vented version so the fill can dry. For a structural concrete slab in a hurricane-resistant building, specify composite floor deck (1.5", 2" or 3") instead. We supply both and can help you match the profile to the drawings.
What Type B is built to carry
The 1.5" Type B wide-rib deck supports roof insulation and membrane and resists wind and seismic loads as a diaphragm. Its published tables are bare-deck values: there is no concrete bond assumed. The vented version has slots that let water escape from lightweight insulating concrete so it dries faster.
When you need a structural slab
Floors, mechanical platforms and concrete roof slabs need composite deck, whose embossments bond with the concrete so deck and slab act together. Our composite deck comes in 1.5", 2" and 3" depths, 22 to 16 gauge, 50 ksi, G60 or G90, with hanger tabs on 20 gauge and heavier.
- Lightweight insulating fill on a roof: vented Type B.
- Structural normal-weight or lightweight concrete slab: composite deck.
- Concrete with a form only, no composite action: form deck (Type S, HD or BI).
Get the profile right before ordering
The structural drawings name the deck. If they show Type B under a structural slab, ask the engineer of record to confirm before you buy. Send us the plans and we will quote the profile they call for.
Related Questions
Why does lightweight fill need vented deck?
Cementitious insulation and lightweight insulating concrete are placed wet. Without an escape path, that water can stay trapped under the roof membrane. The slots in vented Type B let excess water drain downward so the fill dries faster and gives a sound base for the roof. Confirm the fill manufacturer's deck requirements.
Does a concrete slab make a roof more hurricane resistant?
A heavy slab adds dead load that helps resist uplift, but it also raises seismic mass, framing size and cost. Many Florida roofs use steel deck with insulation and membrane fastened for the design wind pressures instead. Which system fits is the engineer of record's call based on the building and its wind exposure.