Environmental sustainability is becoming one of the most important issues in construction.
There are many issues to be considered when improving the sustainability of a building such as:
- Choice of construction material
- Minimisation of environmental impact in use, such as design for low-energy
- Flexibility of design to allow for future adaptation with minimal extra cost or disruption
When designing for environmental sustainability it is important to consider all aspects of the design and construction of a building not just the materials used. When comparing materials, the environmental performance of the material should be compared rather than the properties per weight. For example, when comparing the performance of KingFlor® to plywood formwork, the reduction of steel reinforcement in the slab, as well as the overall reduction of materials required should be considered.
Fielders® are continually looking at ways to reduce steel waste and to keep all steel scrap on the factory floor where it is directly transported to recycling rather than going to land fill. This is evident in Fielders® products being rolled to measure, and new products like AngleCut for which S-Rib Corrugated sheets are cut prior to delivery, reducing on site waste.
National Construction Code (Building Code of Australia)
Changes to the that came into effect in 2016 include the following environmental requirements that must be addressed in a building design:
- Thermal performance
- Building sealing
- Air-conditioning
- Artificial lighting
- Hot water supply
- Access for maintenance
- Material properties
- Ductwork insulation and sealing
- Lighting and power control devices
Life Span of the Building
The life span of the building is an important aspect to consider when determining the environmental impact of material selection. Steel products require minimal on-going maintenance when used and treated in an appropriate manner at the time of original installation. Pre-finished steels such as COLORBOND® steel require minimal on-going maintenance. When maintenance is required there are refurbishment solutions available which will extend the functional lifetime of the building.
R-R-R (Refurbish Re-use Recycle)
Steel is a 100% recyclable material and therefore it is an ideal material for environmental sustainability. The inclusion of steel scrap does not compromise the quality of new steel and is an essential part of steel making to the steel production process. Due to steel’s* magnetic properties it is the easiest material to recover for recycling, and requires 70% less energy than virgin steel to produce.
*excludes SuperDura™ Stainless Steel
Globally, the demand for steel exceeds that which can be derived from scrap alone. This means that, for the time being, virgin steel production is essential for contributing to the developing global infrastructure.
COLORBOND® steel by BlueScope has an average of 25% recovered content (Source).
Thermal Performance
The most important factor to consider when designing an environmentally sustainable building is to reduce the energy required to heat and cool it. A considerable amount of energy used to heat or cool a building is lost due to air leakage. By ensuring that the building is air-tight heating and cooling losses from the building, and therefore energy costs, may be reduced.
When designing a building to minimise the heating and cooling requirements the following factors should be considered:
- Adequate insulation within the building envelope
- The glazed area and its orientation
- Shading Natural ventilation or passive cooling measures
- The colour of the cladding
BlueScope offers guidance for the solar absorption of its COLORBOND® steel range and ZINCALUME® steel in accordance with both the NCC and New South Wales BASIX “DD SEC MS 001”. Check here for updates to the colour range.
Steel sheeting is inherently an airtight material, however caution needs to be taken when treating the ends to ensure that there is no leakage at the interface with other materials. Metal roofing provides negligible thermal resistance on its own and insulation should be used to increase the thermal performance of the system. Insulation is the single most effective way of improving a building’s energy efficiency. Typically insulation products installed during construction will last for the life of the building with very little or no maintenance.
The easiest and lowest cost method is to include insulation at the construction stage of a project such as roofing blankets, incorporating bulk insulation with a reflective Sisalation foil. These products provide significant levels of thermal insulation and also help to reduce noise and control condensation. Where higher levels of insulation are required, insulation may also be installed into the roof and wall cavities during construction.
Additionally, many insulation blankets or batts l contain approximately 70% recycled glass, helping to conserve our natural resources.
To minimise deck bulge with thicker insulations and to reduce the thermal bridging effect at purlins we recommend the use of a roof spacer.
For more information on Fielders® products and environmental sustainability contact your local Fielders® representative.