This is madness

The UK construction industry generates more than 100 million tonnes of waste every year – and we’re running out of holes to dump the stuff in.

Running out of money, too. Disposal costs can only go up – landfill tax is being ratcheted up and an increasing number of materials are being classified as hazardous. Yet the number of sites where hazardous waste can be deposited legally has been reduced to a handful, meaning long, expensive journeys have to be undertaken to get rid of it. Above all, as the climate of opinion changes, it is becoming unacceptable to chuck away perfectly good materials that could be reused. The Major Contractors Group has cottoned onto this and has just published a sustainability charter that includes targets for waste reduction.

There’s a strong business case, too. According to Simons Construction, the cost of physically carting away waste amounts to 0.4% of a project’s total cost. But that does not take into account the expense of procuring and handling the materials before then – indeed, WRAP estimates that the value of materials thrown away is 15 times more than the cost of disposal, which equates to 6% project value. Bearing in mind that a contractor’s margin will be a small fraction of that, it’s a lot of money.

“The fundamental driver behind waste reduction is that the business benefits,” says Mervyn Jones, special projects officer at WRAP. “Clearly waste management has a significant effect on the bottom line of construction projects.”

Many big contractors have realised this and are beginning to manage their waste more efficiently. Simons found that after implementing a recycling policy it reduced the amount of material it sent to landfill by at least 60%, and reduced the cost of disposal by 40%. Other major contractors have a range of initiatives to help hit waste reduction targets: Skanska employs full-time “marshals” to ensure trade contractors segregate their waste on site; Seddon Construction owns and operates a waste transfer station to recycle 90% of its waste; and Wates has set itself a target of zero waste by 2010 (see “10 essential steps towards waste-free construction”, below).

Much more needs to be done, however. “Typically 60% of a construction project’s waste is recycled and that could be easily pushed up to 80%,” says WRAP’s Jones. He adds that the recycled waste is mostly hardcore, soil and rubble, and that there have been “significant improvements in the recycling of aggregates”.

We are importing wood pellets for biofuel boilers while dumping timber in landfill where it produces methane

But the industry needs to turn its attention to other materials. Legislation to segregate plasterboard offcuts has prompted British Gypsum, Knauf and Lafarge to use them to make new board, and Wates is recycling PVCu windows from a housing upgrade scheme. But timber’s recycling potential remains unexploited.

“Timber recycling is the next big thing that would make a difference to the construction waste stream,” says Barry Smith, environment manager at Simons Group. It makes up 28% of all construction waste – 25 million tonnes of it are chucked away each year. The problem is that the Environment Agency classifies timber from construction sites as waste. “Once it’s described as waste, it’s stigmatised,” says Smith. “It’s dirty, messy and much more expensive to handle.”

He adds that we are in the crazy situation of importing wood pellets from Russia and Canada to burn in our ever more popular biofuel boilers while dumping timber in landfill sites where it produces methane, a greenhouse gas 20 times more potent than carbon dioxide. Smith says the legislation needs urgent revision so timber can be more easily recycled.

Smaller companies also need to raise their game. WRAP surveyed the industry to find out how many were using site waste management plans, or using one available from the DTI. But Jones says: “We found only 13% of the sector was using any type of site waste management plan and only 3% was taking up the DTI’s.”

This could be about to change, however. The DTI is consulting on whether to make the plans compulsory next year for all projects worth more than £200,000, so the wider industry may be compelled to change its bad habit. The good news is that reducing waste is not rocket science. At a basic level, all a contractor has to do is get in touch with a support services firm that sorts and recycles waste. It can order skips in the normal way and chuck waste in them as before, because the waste specialist will separate them at its waste transfer station. To start saving money though, contractors need to segregate waste on site, which can mean waste collection is free for some types of valuable waste, such as metals, and much cheaper for inert material such as hardcore – it costs £10-15 tonne to dispose of inert material rather than £75-100 tonne for general waste. But really cracking the waste problem requires a more strategic approach, starting with the architect. See our 10-point plan …