uPVC Wall Construction Systems
What are PVC Wall Systems?
PVC Wall Systems are strong, lightweight, easy to install and cost effective for a variety of construction applications. Developed in Australia, these new generation concrete-filled PVC stay-in-place (SIP) formwork wall construction systems offer significant benefits in terms of construction timeframes, life cycle costs and better energy performance.
This type of permanent formwork can contribute to a Responsible Building Materials credit under the Green Building Council of Australia’s Green Star rating tool.
Where do they work?
Modular SIP systems with proprietary components that use individually designed connecting moulds and systems are available in Australia. These new systems can be used effectively to replace load-bearing conventional precast concrete, tilt-up or masonry block walls. Today, they are used for basements, stair and lift shafts, blade columns, irrigation tanks, retaining walls and other areas, and in buildings up to 60 storeys high.
What are the benefits?
- Cost effective and rapid assembly
Traditional, temporary formwork using timber, plywood or steel is labour intensive, representing 40 to 60 per cent of the total cost of a concrete structure. Materials such as glass-reinforced plastic, fibre-reinforced plastic, thermoplastics (PVC, polystyrene) fibre cement and metals can be used to pre-fabricate formwork for permanent systems that remain in place for the life of the building. Interconnecting components create formwork that can be erected highly efficiently.
Using a PVC Wall System helps to overcome drawbacks associated with concrete’s poor tensile strength requiring reinforcement, propensity to crack under sustained pressures such as in basements and retaining walls, and its porosity, which can lead to ‘concrete cancer’.
The plastic formwork seals the concrete, acting as a water-resistant barrier that protects it from the environment for the life of the building. Connectors in the latest SIP formwork systems allow for rapid installation and core-filling, with usually no need to vibrate and settle the concrete.
In some systems, the quantity of cement can be reduced and substituted with an increased amount of fly ash or aggregates without raising concerns of concrete cancer.
- Reduced environmental impacts and injury risks
Technically advanced PVC Wall Systems have the potential to reduce the environmental impacts, as well as health and safety risks, on construction sites. Some of the newest systems require less steel reinforcement, reducing materials consumption and the building’s carbon footprint.
As there is no need for stripping SIP formwork, combined with its lightweight and ease of installation, injury risk is reduced thereby contributing to improved health and safety on site.
The lightweight advantages of some modular systems mean that they may need bracing, due to susceptibility to wind load, before the concrete pour. Therefore, it is critical to ensure that any modifications to a SIP formwork system’s mould design or the use of a combination of two systems’ components is checked and signed off by suitably qualified professionals because of the proprietary, and differing, nature of systems in the market.
Advantages of PVC Wall Systems
Cost savings, construction time savings and ease of installation are key attractions to the systems cited by companies using PVC Wall Systems. Their decision to use permanent formwork over traditional or masonry alternatives can also be driven by site requirements, particularly where there are water issues, retaining wall requirements and project design requirements, such as multi-storey underground basements.
SIP systems have been shown to benefit projects from an environmental and safety perspective through:
• Transport energy savings
• Significant reductions in embodied energy of materials
• Better site safety
• Reduced long-term maintenance
• Above and below ground versatility
• High level of industry safety and compliance
• High fire resistance
• Easy handling and installation
Some of the latest systems have been certified to meet earthquake and bushfire requirements, therefore capable of contributing to the need in Australia for a more resilient future built environment.