Gareth Moores, managing director of Lytag Ltd, explains how using lightweight, secondary aggregate in precast concrete can help construction project teams meet the dual goals of improving sustainability credentials and delivering more for less…
There is no doubt that the push for a more environmentally sustainable built environment has forever altered the construction industry. Sustainability has become ingrained at all levels, from the development of “green” products and techniques to the modification of construction processes to reduce waste and the establishment of new energy efficiency targets and legislation.
Moving forward, the challenge will be to combine a truly sustainable offer while continuing to find new ways to cut costs and deliver more for less. Approaches that can assist a construction project team in achieving both of these goals are already gaining traction.
Precast concrete made with lightweight secondary aggregate is one such approach. This provides a simple, tried-and-tested ‘quick win’ that has been used successfully across the UK and beyond to reduce the environmental impact of projects while also improving their bottom lines.
Using a pre-cast concrete system can provide significant benefits in terms of sustainability and cost-efficiency. Rather than doing all of the concrete work on-site, the precast concrete modules are built off-site before being installed on-site, reducing material waste. It can also significantly reduce the amount of time, labour, and energy consumed on-site, all of which can reduce project timelines and costs while also improving environmental credentials.
The use of lightweight secondary aggregate in the manufacture of precast concrete increases both the environmental and cost benefits.
Increasing Environmental Credibility
LYTAG lightweight aggregate (LWA) is an excellent example of a high-quality, everyday material that can be used in the same way as traditional aggregate while also making a building more environmentally friendly.
Made from pulverised fuel ash (a by-product of coal-fired power stations), its use in place of traditional materials ensures that pulverised fuel ash is used rather than discarded, while also reducing the demand for finite and quarried aggregate. Furthermore, external walls cast with LYTAG LWA have better thermal insulation than those cast with normal weight aggregate – something that is more important than ever as energy prices rise and building energy efficiency remains a focus of Government sustainability policy and targets.
For over four decades, the construction industry has used LYTAG LWA in a variety of applications such as structural and precast concrete, screeds, fill, and drainage medium. It is also commonly used in precast products such as bespoke units, lintels, kerbs, and floor panels.
Secondary LWA is an effective ‘quick win’ to implement as client demand and government legislation to reduce the environmental impact of construction continue to grow. LYTAG LWA’s lightweight quality, in addition to its sustainability credentials, makes it an ideal choice for use in pre-cast concrete, helping to increase productivity by reducing unit weights or producing larger units of the same weight.
Increasing the Business Advantages of LWA
Aside from its ‘green’ benefits, secondary LWA can offer clients and project teams a variety of advantages in terms of performance, engineering flexibility, project timeframes, and costs. LWA enables the delivery of structures that would be impossible or would necessitate design or timescale compromises with heavier material.
When used in precast concrete, LYTAG lightweight aggregate can save up to 25% more weight than standard-weight precast concrete. These weight savings can translate into significant business benefits in terms of production techniques, reduced fixings, logistics, and crane requirements. Larger pre-cast panels can also be cast, reducing the number of joints, accelerating construction, and lowering mould costs.
Furthermore, engineers and designers will have more flexibility in terms of weight constraints. Because of the weight savings, building spaces can be designed with larger structures and greater spans, as well as a reduced number and width of columns, ultimately providing building owners and occupiers with more usable floor space and increased commercial value.
Many engineers and contractors have made resource efficiency a priority in recent years, reducing waste and delivering energy-efficient buildings, resulting in cost savings and job wins. Precast concrete made of lightweight secondary aggregate is a quick win that provides a solution. It is a tried-and-true method of assisting clients, industry, and government in meeting sustainability requirements, while the potential business benefits offered by the material are benefits that the industry cannot afford to overlook.