Floor Slabs

About Floor Slabs

The first thing laid on foundations during building construction is a floor slab. Also known as plate or filigree slab, it’s commonly made from reinforced concrete and poured on-site with an average thickness ranging between 5 and 30 cm. The thickness depends on the span the slab needs to bridge, as well as the loading it’s designed to withstand. Concrete slabs can be transformed into a solid or monolithic concrete floor.

The precast concrete used for slabs is produced in a component factory under controlled conditions. Consequently, the finished piece combines the major advantages of prefabrication with the benefits of floors built on-site from scratch by pouring concrete into the casing. It contains the torsionally rigid reinforcement that will provide strength once installed. The flexural tension reinforcement, applied crossways and along the lengthways, is also required for proper modelling and the final state.

Floor Slabs Application 

A floor slab is a flat horizontal structural element that serves as a floor/ceiling of a basement, depending on the position - whether it’s applied at a ground level or at upper levels. Its role is to diffuse the load applied to it from elements above to whatever lies below. An adequately produced floor slab must distribute the load to the lower part of the structure or the foundation without facing deformations or cracking.

Concrete slabs composing the ground floor of a building can be supported by beams or placed directly on the subsoil.

A concrete slab applied as a roofing segment is commonly referred to as the “roof slab”.

Types of Floor Slabs

The term “floor slab” indicates a finished result achieved by a variety of methods. Standard types of floor slabs can be identified according to these differences.

Flat 

A flat slab commonly refers to a reinforced slab carried by columns or caps, without the need for additional beams. It’s cost-efficient, easy to install, and requires little labour force. 

Conventional

This type of slab transfers the load to the beams, columns, foundation piles, or other elements that support it. It falls into two different categories:

• One-way: This style carries the load in a single direction, supported by beams on opposite sides.
• Two-way: As the name indicates, this type transfers the load along with two directions, and needs to be beam-supported on all four sides.

Hollow-Core Ribbed

With a multitude of longitudinal forces running through it, this type of slab boasts a lighter weight than other models. Subsequently, a lower amount of concrete is required in its production, making it a very cost-efficient option. This type is commonly reinforced with longitudinal rebar and able to bridge long spans. Hollow-core rebar design can function as service ducts, suitable for a variety of commercial applications such as multi-floor car parks, office buildings, and similar. 

Waffle Slab

This type is named by the square grids with deep sides characterising its structural appearance, reminiscent of a waffle shape. Such form is obtained by pouring concrete over a set of plastic formers, creating a desired hollow formation on the slab’s underside. This specific design gives them the ability to support a greater load than their conventional counterparts. 

Waffle slabs can boast a thickness of over 50 cm while remaining exceptionally lightweight, economical, and structurally efficient. For that reason, the ideal application of waffle slabs is in bridging large spans, in spaces where installing a multitude of carrying columns is not an option. 

Solid Slab Raft

A solid raft is a shallow foundation created by a reinforced concrete slab covering a vast area that could span over the entire footprint of a building. It disperses the load forced by several walls, columns, and other structural elements while “floating” on the ground in a similar way to a raft drifting on the water - hence the name. Its ideal application is on weak soils such as peat or clay.

Composite Slab

Composite slabs are commonly made from reinforced concrete with a thickness minimum of 12 cm. They feature a profiled steel decking for added strength against deflections and vibrations. The key advantages of composite slabs are versatility, adaptability, and their resistance to weight ratio. 

Concrete Floor Styles

A floor consisting of solid concrete is practical and often utilised in homes placed on a slab-on-grade foundation, particularly in basements. In more utilitarian environments, such as industrial applications, a concrete slab can be easily smoothed for more convenient use. At the same time, a range of decorative indoor floor treatments allows customisation of its surface, ideal for various residential and commercial decor schemes. 

The treatments include:

• Polishing and sealing: This creates a reflective, smooth, glass-like surface.
• Colouring with dye: A broad palette of colours and finishes can suit a range of different interior design styles.
• Treating with acid: Another way to produce a coloured surface with a texture. 
• Coating with epoxy: A convenient, highly functional finish with decorative quality. 

Things to Consider Before Buying Floor Slabs

One of the crucial factors to know before buying a pre-mixed concrete for a slab is the required compressive strength. Reinforced concrete strength commonly ranges:

• From 3,500 to 4,000 psi for slabs on grade
• From 3,500 to 5,000 psi for use in suspended slabs, girders, and beams
• From 3,000 to 5,000 psi for columns and walls 

Other details, such as aggregate style and diameter, must also be specified, depending on the spacing of reinforcing steel, slab dimensions, and available aggregates.

If you need assistance to find the right floor slabs for your home or office, ArchiPro provides a connection to the various professionals, ready to assist with all requirements and questions. Simply click "Contact supplier" on the product's page, or visit the supplier's website directly from the product's page.