What Is Floating Slab | Floating Slab Construction | How to Build a Floating Slab | Advantages & Disadvantages Floating Slabs

What Is Floating Slab?

The term floating slab refers to a two-stage slab construction, where footings are individually. poured, and the centre floor of the slab is poured after footings have cured. The forms of a monolithic slab are designed so that both footing and slab floor are poured at the same time.

Floating Concrete Slab–

Floating slabs are concrete slabs that are laying over the ground, without any kind of anchoring, as if it simply sits on it and floats. The main application of floating slabs is to use as a base foundation for sheds, manufacturing workshops, home additional room, or garages.

Why Use a Floating Slab?

Floating slabs behave as a barrier for the entrance of the moisture coming from the ground. It acts a barrier between the superstructure and the ground. This avoids seepage of water and frosting. For this purpose, the slab can be insulated for frost or moisture.

Advantages of Floating Slabs:

• The floating slab construction can be employed in site areas with lower load carrying capacity and where investing large money on soil treatment is futile.
• Floating slab have the property of spreading the vertical loads or stresses coming over it to be distributed over a larger area.

Disadvantages of Floating Slabs:

• The floating slab does not make underground land available for underground access for connection lines facing the utilities.
• It has a primitive technology.
• Floating slab foundation have lower design resonance.

Float Slab:

The term floating slab refers to a two-stage slab construction, where footings are individually. poured, and the centre floor of the slab is poured after footings have cured. The forms of a monolithic slab are designed so that both footing and slab floor are poured at the same time.

Floated Concrete Floor

Power floating concrete floors is a technique used with a power trowel, a finishing machine utilized to smooth and even the surface of the concrete to an exceptionally high tolerance.

Floating Slab Construction Cost

A typical 1,200-square-foot house foundation costs $6,900 to $16,200 for a concrete slab, or about $40,000 for a full unfinished basement. A floating slab for a mobile home runs $4,600 to $14,000, while a standard 24′ x 24′, 2-car garage foundation costs $3,100 to $4,800.

Floating Slab Vs. Traditional Foundation

Here are the differences between a floating slab and a traditional foundation:

Floating Slab:

• Construction: A floating slab is a single-layer concrete slab poured directly onto the ground without any deeper footings. It “floats” on the soil.
• Footings: Floating slabs do not have deep footings or basement walls like traditional foundations.
• Stability: They rely on the strength and stability of the soil to support the load of the structure.
• Cost: Floating slabs are generally less expensive to construct compared to traditional foundations due to their simpler design and reduced materials.

Traditional Foundation:

• Construction: A traditional foundation consists of deep footings, basement walls, and a concrete slab or crawl space.
• Footings: Traditional foundations have deep footings that extend below the frost line to provide stability and support for the structure.
• Stability: They provide greater stability and resistance to soil movement, settling, and potential damage from moisture.
  Design Flexibility: Traditional foundations offer more design flexibility, allowing for multiple levels, basements, and crawl spaces.

Advantages of Floating Slab Foundation

Slab reduces the soil pressure under the foundation. Since the stiffness of the slab can be modified in the area where required, economize construction can be done. Floating slabs avoid the water seepages in the areas where the water table is high.

Floating Slab Design Considerations

When considering the design of a floating slab, there are several important factors to take into account. Here are some key considerations:

• Soil Assessment: Conduct a thorough soil investigation to determine the soil type, bearing capacity, and potential for settlement. The stability and load-bearing capacity of the soil will affect the design and thickness of the floating slab.
• Structural Design: The design of the floating slab should be based on the anticipated loads from the structure it will support. Consider factors such as building dimensions, weight, and any additional loads, such as snow or wind, that need to be accounted for in the design.
• Thickness: The thickness of the floating slab should be adequate to distribute the load uniformly and prevent cracking or settlement. It should be determined based on soil conditions, expected loads, and local building codes.

Floating Slab Construction Process

The construction involves the following steps:

1. Fig.1: Floating Slab Layers.
2. Fig.2: Preparation of land by removing the upper layer.
3. Fig.3: Excavated drainage and the prepared drainage.
4. Fig.4: Laying Gravel base layer over the area for drainage of unwanted water.
5. Fig.6: Compaction of Poured Concrete.

How to Make a Floating Concrete Slab?

To create a floating concrete slab, you’ll need to follow a specific process. Here’s a step-by-step guide on how to make a floating concrete slab:

• Prepare the area: Clear the site where you want to construct the floating concrete slab. Remove any vegetation, rocks, or debris. Level the ground to ensure a flat and stable base.
• Excavation: Dig a trench around the perimeter of the slab area. The depth of the trench should be determined based on the frost line in your region, typically around 6 to 12 inches (15 to 30 cm) deep.
• Install formwork: Construct wooden or metal forms to create a framework for the slab. The forms will contain the concrete while it sets. Ensure that the forms are level and securely staked into the ground.
• Add a layer of gravel: Place a layer of compacted gravel inside the formwork. This provides a stable base and helps with drainage. The thickness of the gravel layer should be around 4 to 6 inches (10 to 15 cm).

Floating Garage Floor

If you’re specifically looking to create a floating garage floor, the process is similar to making a floating concrete slab. Here’s a modified step-by-step guide for constructing a floating garage floor:

• Prepare the area: Clear the garage area and remove any items or obstacles. Make sure the floor is clean and free from debris.
• Determine the desired height: Decide on the height of the floating garage floor, taking into consideration any required slopes for drainage and the existing height of the garage entrance.
• Install formwork: Construct formwork around the perimeter of the garage floor area. The formwork should be strong and level to hold the concrete in place. Use stakes or other support to secure the formwork.
• Excavation (if needed): If the existing garage floor needs to be removed or if you need to create a lower level for the floating floor, excavate the area accordingly. Follow the same steps as mentioned earlier for excavation.
• Add a layer of gravel: Place a layer of compacted gravel inside the formwork. This layer serves as a stable base and helps with drainage. The thickness of the gravel layer should be around 4 to 6 inches (10 to 15 cm).

What Is a Floating Slab?

Floating slabs are concrete slabs that are laying over the ground, without any kind of anchoring, as if it simply sits on it and floats. Floating slab, as the name tells it resembles a plate that is simply laid over water, with no kind of connection between them.

Explain What Is Floating Slab Foundation

2. A Floating Slab Foundation. A floating slab foundation also includes a concrete footer, but the exterior walls are built directly on top of the footer. The slab floor is poured after this, meaning that it “floats” or rests on the footing but doesn’t support as much of the building’s structure.

How to Float a Concrete Floor?

The term “floating” refers to the application of pressure so a float sits lightly and flatly just on top of the surface of the poured concrete and pushes the aggregate down, allowing the liquid in the concrete to rise, dry, and create a smoother surface.

Floating Slab Foundation

A floating slab foundation, also known as a “floating concrete slab,” is a type of foundation that is commonly used for small structures like sheds, garages, or workshops. Unlike traditional foundations that are deeply anchored into the ground, a floating slab foundation sits directly on the surface.

How Thick Should a Floating Slab Be?

For every 2 feet of adjustment to the width of the house add or subtract 2 inches of footing width and 1 inch of footing thickness (but not less than 6 inches thick).

Floating Slab Vs Monolithic Slab

Floating slabs are idle for house addition and garages on the soil with low bearing capacity. In comparison, the monolithic slabs are suitable for the level and well-compacted ground with a low slope.