How much waste do you think the average construction worker produces in seven days? If you were guessing around 50kg or 100kg you are in for a big shock. The UK's construction managers, designers, and site staff are each responsible for more than 1,000t of waste every week - and that's without including their own personal refuse.
With the number of landfill sites close to saturation point in some parts of Britain and landfill tax currently under review, it is clear that the industry is going to have think more seriously about what it throws away. Today (Thursday) the Construction Industry Research & Information Association is launching a new guide and training pack Waste minimisation in construction. Through the guidance CIRIA hopes to encourage construction companies to take a more pro-active approach to reducing waste and making better use of recycled materials.
'With increasing costs people are starting to think of alternatives to minimise waste and re-use materials. We've tried to provide some practical guidance on how to best do that,' says CIRIA group manager for the environment Jon Bootland.
The suggestions include re-cycling waste, specifying reclaimed materials wherever possible and reducing waste volumes through more careful storage. This is all very worthy, but such measures require more time and better planning than traditional site and design practice. The market for reclaimed materials is relatively undeveloped, and extra staff may be needed to segregate re-usable waste from that which simply has to go to the tip.
Because of this, Bootland claims many engineers are still cynical about minimising waste. Yet if they cannot be persuaded to take up the gauntlet on environmental grounds, they should at least face the economic facts. The true cost of waste, he says, is not simply the cost of its disposal. It also includes the original purchase price of the materials, the costs of transport and storage, and the loss of income from not salvaging waste.
Bootland reckons that better waste management would make many contractors more competitive, and could offset some of the other costs of construction.
'The more astute companies are already starting to recognise that there is a business opportunity in reclaiming and re-packaging construction materials,' he says.
But there is only so much 'end of pipe' work that can be done. To achieve a major reduction in construction waste more needs to be done at the design stage.
'People on site know the cost of ordering materials and disposing of waste,' says Bootland. 'Better design would have a much more significant impact than the effects of better site management.'
The CIRIA guide claims that many construction projects are overdesigned, leading to greater waste volumes during their construction and greater waste once they have reached the end of their design lives. While safety of engineering solutions will always be paramount, CIRIA reckons that closer analysis of design loading could save up to 30% in materials.
The design life of a project should also come under closer scrutiny, says Bootland. Many projects have in the past been too inflexible to last out their design lives and have had to be demolished prematurely.
'For example, if a building is designed to last 100 years but is only flexible enough to suit the requirements of one or two tenants it will be pulled down after 30 years. That is a waste,' says Bootland.
In the future Bootland reckons that engineers will have to take the whole life of projects into greater account.
'Structures should be designed so that they are easier to take apart and less waste is produced. I call it designing for dismantling,' he says. Ultimately this will mean marking materials which cannot be re-used so that they don't contaminate those which will be recycled.
Bootland admits that this is still some way off, but warns that engineers cannot afford to ignore the guidance. 'It's going to get more and more important to minimise waste and there are going to be more regulations coming along to force people to do it. The sooner people start thinking about this the better.'