Properly selecting the material for subflooring is essential to ensure the durability of the entire structure and allow for an aesthetically pleasing finish. However, during the subfloor construction phase, many questions arise: what to choose — foam concrete or styrofoam? Which flooring will last for many years without causing costly replacement issues? In this article, we will address all these questions.
Properties of Foam Concrete Floors
Concrete for floors is essentially an ideal material. Its excellent load-bearing capacity, resistance to compressive loads, and thermal insulation are just a few of its many advantages. When it comes to foam concrete, it stands out for its remarkable lightness despite these properties. So, what is foam concrete? How does it differ from standard concrete for floors? It is a type of concrete in liquid form, making it perfect as a base for floors and thermal insulation. Foam concrete is made by adding technical foam to Portland cement. This concrete contains closed cells, making it several times lighter than traditional concrete. Comparing foam concrete to a traditional subfloor made with sand, styrofoam, and reinforced concrete, results in a much lighter construction. For example, a subfloor of 100 m² with a thickness of 30 cm made from foam concrete will weigh about 15 tons. This is significantly less than the weight of a standard concrete subfloor of the same dimensions, which can weigh up to 100 tons.
Unlike styrofoam subfloors, foam concrete creates a monolithic and stable base. It does not shrink or settle over time. Foam concrete also does not require expansion joints during preparation, which are used to separate different construction elements. Another advantage of choosing this material for subfloors is its excellent thermal insulation. A floor made with foam concrete in homes will be very warm: 20 cm of foam concrete replaces a 10 cm layer of styrofoam, maintaining the same thermal insulation properties. Using 60 cm of foam concrete provides insulation equivalent to 30 cm of styrofoam. Foam concrete used for subflooring has several advantages, including:
- Load-bearing structure,
- Compression and load resistance,
- Lightness compared to conventional flooring,
- Thermal insulation properties,
- No need for expansion joints,
- No shrinking or settling over time,
- Does not require perfectly even subfloors,
- Soundproofing and vibration damping properties.
An important point to mention is the excellent adaptability of foam concrete to the subfloor. Unlike styrofoam, foam concrete does not require the base to be perfectly even, avoiding issues like buckling and floor drumming. Additionally, foam concrete eliminates thermal bridges present with unevenly laid styrofoam. Therefore, a foam concrete screed serves as an excellent base for subsequent floor layers, filling empty spaces and leveling the subfloor.
What About Styrofoam? Is It Worth Using?
Investors are undoubtedly attracted by the excellent thermal properties and versatility of styrofoam, which can insulate the entire building. However, despite its good thermal insulation parameters, styrofoam is not without flaws. A floor with styrofoam will not be a monolithic and stable base, posing risks of settling and buckling due to uneven material placement. Unfortunately, the list of disadvantages of using styrofoam as a flooring material is longer than its advantages. The most significant disadvantages include:
- Instability of the material,
- Inability to create a monolithic base,
- Risk of buckling and settling,
- Lack of resistance to chemicals,
- Inability to perfectly seal plumbing and water installations,
- Floor drumming effect,
- Lack of fire resistance,
- Creating ideal living conditions for insects and small rodents.
Building floors with styrofoam poses considerable challenges, especially if the investor aims to securely seal installations in the floor. Plumbing, water, and ventilation pipes will be much better sealed and protected against displacement when using foam concrete. Unfortunately, styrofoam will not perform well in this regard and may even disappear over time due to fire or rodent infestation.
Time to Complete Foam Concrete Floors
Floors using foam concrete are characterized by their rapid completion time. High-efficiency machines used to produce this material are primarily responsible for the quick preparation of the subfloor. Preparing a concrete floor of 1000 m² and 20 cm thickness takes one day. This is possible thanks to machines achieving a production rate of up to 25 m³ per hour. Concrete flooring also does not require very high ambient temperatures for efficient and quick drying. If the air temperature exceeds 18°C, the floor is ready in just over a day. After this short time, foam concrete can be used to lay underfloor heating installations and another concrete screed can be applied.
Foam Concrete or Styrofoam — Which Is More Cost-Effective?
It might seem that a styrofoam floor would be much less expensive than foam concrete. However, this is a misconception. In reality, foam concrete ultimately proves to be a more economical subflooring method. A foam concrete floor eliminates other costs associated with traditional subfloor construction methods. A concrete floor does not require materials such as sand, styrofoam, or lean concrete for subfloors. Using foam concrete also means lower labor costs compared to other flooring materials. Foam concrete instead of styrofoam is a much more advantageous solution not only in terms of cost but also durability. A concrete screed will perform excellently in both single-family homes and larger buildings. Foam concrete is an excellent solution if you are looking for a monolithic and stable base at an affordable price.