The waffle pod slab system is one of the best ways to create a solid foundation for a building. Waffle pods are called such because the bottom surface of a waffle slab system resembles a waffle (who knew that a delightful snack could also refer to a key element in construction?) In this article, learn everything about the waffle slab system – what it is, how it works, and its advantages.
Characteristics of a waffle pod slab system
Basic description
A waffle slab is flat on top, but the bottom surface features a grid-like structure created by joists. Waffle pods, made of polystyrene material, are arranged in a grid pattern. Each waffle pod is separated by some amount of space, and these gaps are fitted with steel reinforcing. Reinforcement (mesh or individual bars) is also placed around and above the whole arrangement of pods. The waffle-like pattern is achieved when the polystyrene waffle pods are removed after concrete has been poured.
Measurements
- Thickness: 85 to 100 mm
- Overall depth: 300 to 600 mm
- Width of beams and/or ribs: 110 to 200 mm
- Spacing of ribs: 600 to 1500 mm
Construction process
A waffle pod slab is built on-ground instead of in-ground. This means that trenching would not be necessary, unlike in the conventional slab method. For as long as the ground on which the slab is installed is flat (or flattened and cleared out beforehand), a waffle slab should be able to work as a solid foundation for a new home, establishment, or an extension to either of these buildings.
There are three main ways to create a slab system: in-situ, precast, and prefabricated.
‘In situ’ is a Latin phrase that means “on site” or “in position.” When a waffle slab is constructed in-situ, concrete is poured onto the arrangement, which turns the steel reinforcements in between the pods into what slab system terminology refers to as ‘ribs.’ These ribs are what make the slab strong and consistent, which allows it to hold up whatever would be built on top of it.
A precast waffle slab involves creating slab panels beforehand and later joining them together with steel reinforcement and concrete fillings on-site.
A prefabricated waffle slab involves manufacturing reinforcements, and then directly integrating them into the slab. They would not need further reinforcement on site, but this method is the most expensive one of the three.
Advantages of the waffle slab system
It is best used for spans greater than forty feet.
Waffle slabs are much stronger than flat slabs, two or one-way slabs, and one-way joist slabs. One of the reasons for this is that the waffle slab system offers impressive load carrying capacity, meaning the weight of the structure built on top of it can be supported effectively due to the slab’s grid feature.
Get more for less.
Another reason is that it is simply the more economical choice – the structure itself offers an opportunity to achieve a wide span with much less material. The fact that the slab is hollowed out in squares at the bottom means that much less concrete is needed to achieve the design.
Keep vibration at the lowest levels.
Buildings that require less vibration will benefit from having a waffle slab system as its foundation. Its two-directional reinforcement offers good vibration control capacity. This means it would be great for public establishments like hospitals, airports, places of worship, or other spaces that can expect high foot traffic. These are also spaces that are much larger than most and would, therefore, require greater spans.
The structure itself supports utility systems.
Services can be implemented within the waffle slab system. Lighting, plumbing pipes, electrical wiring, HVAC, and other utilities can be installed by creating holes in the bottom surface. Wires and pipes can run through the hollow squares. Many find this to be a neat and economical way to install utility systems within a building.
It saves you money.
A waffle slab system is simply the more cost-effective option. It will cost around 30 percent less than other conventional slabs. Even then, it still is stronger than conventional slabs, because it has more beams and closer centres. Conventional slabs use much more concrete, as soil should be prevented from collapsing into the trenches during the beam construction process.
There is minimal environmental impact involved.
There’s no disturbance being done to the environment during a waffle slab system’s construction process. With the need for trenching out the window, soil can stay intact. Also, the process does not produce any excavated rubble.
Need quality waffle pods for your next waffle slab system construction project? We at Queensland Polystyrene Specialists can provide them for you
Having worked with Queensland’s builders for over fifteen years, we know how important it is for your waffle pods to be delivered on time and in the best quality. We deliver pods as well as spacers and clear plastic recycling bags over to your project site. We will also come in to collect polystyrene off cuts as they will be recycled. Our polystyrene waffle pods are made from Expanded Polystyrene, which helps you create a well-insulated slab.
Enquire about our polystyrene pods today. Call us at 07 3274 1194 or email us at sales@qldpoly.com.au.
