Gareth Moores, managing director of Lytag Ltd, explains how using lightweight, secondary aggregate in precast concrete can help construction project teams to deliver against the dual priorities of improving sustainability credentials and finding ways to deliver more for less…
There is no question that the drive for a more environmentally sustainable built environment has changed the construction industry for ever. Sustainability has become embedded at all levels, from the development of ‘green’ products and techniques, to the adaptation of construction processes to minimise waste, to the creation of new energy efficiency targets and legislation.
Moving forwards, the challenge is how to combine a genuinely sustainable offer while continuing to find new ways to trim budgets and to deliver more for less. Approaches that can help a construction project team to achieve both of these goals are already growing in popularity.
One such approach is using precast concrete made with lightweight secondary aggregate. This offers a simple, tried-and-tested ‘quick win’ which has been used to good effect across the UK and beyond, to lower the environmental impact of projects while also improving their bottom lines.
There are considerable sustainability and cost-efficiency benefits that can be achieved through using a pre-cast concrete system. Rather than undertaking all the concrete work onsite, the precast concrete modules are created off-site before being installed on site which helps to minimise material wastage. It can also significantly reduce the time, labour and energy consumption that are required on site – all of which can reduce project timeframes and costs as well as improving environmental credentials.
By using lightweight secondary aggregate to make the precast concrete, both the environmental and cost benefits are enhanced further.
Enhancing the Environmental Credentials
LYTAG lightweight aggregate (LWA) is a prime example of a high quality, everyday material that can be used in the same way as traditional aggregate, but can also make a building more sustainable.
Manufactured from pulverised fuel ash (the by-product of coal-fired power stations) its use in the place of traditional materials ensures that pulverised fuel ash is used rather than sent to landfill, as well as reducing the demand on finite and quarried aggregate. In addition, external walls cast with concrete made from LYTAG LWA also have improved thermal insulation over those cast with normal weight aggregate – more important than ever as energy prices rise and the energy efficiency of buildings remains a focus of Government sustainability policy and targets.
LYTAG LWA has been used for over forty years by the construction industry in a variety of applications including structural and precast concrete, screeds, as fill and as a drainage medium. It is also commonly used in precast products ranging from bespoke units to staircases, lintels, kerbs and floor panels.
As client demand and government legislation to lower the environmental impact of construction look set to keep growing, using secondary LWA is an effective ‘quick win’ to implement. But in addition to its sustainability credentials, the lightweight quality of LYTAG LWA 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 Benefits with LWA
In addition to its ‘green’ advantages, secondary LWA can provide clients and project teams with a number of benefits in terms of performance, engineering flexibility, project timeframes and costs. LWA allows the delivery of structures that would be unachievable or require design or timescale compromises with heavier material.
Used in precast concrete, LYTAG lightweight aggregate can provide a weight saving of 25% over normal-weight precast concrete. These weight savings can lead to significant business advantages in terms of production techniques, reduced fixings, logistics and crane requirements. Larger pre-cast panels can also be cast, which reduces the number of joints, speeds up construction and cuts mould costs.
In addition, greater flexibility can be afforded to engineers and designers in terms of weight constraints. The weight savings can mean that spaces in buildings can be designed with larger structures and greater spans and a reduced number and width of columns, ultimately providing building owners and occupiers with maximised usable floor space and increased commercial value.
Many engineers and contractors have made using resources efficiently a priority over recent years, cutting waste and delivering energy efficient buildings, securing cost savings and winning work as a result. Using precast concrete made with lightweight, secondary aggregate is a quick win that provides a solution. It is a tried-and-tested way to help meet sustainability requirements set by clients, industry and Government, while the potential business advantages the material offers are benefits that the industry can not afford to ignore.