On the average job, contractors happily chuck away enough recyclable material to triple their profit. But not for much longer, if the DTI, environmental responsibility and economic sanity have any bearing on the matter.

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 …

How Wates is eliminating waste – with a little help from the Hippos

Wates Group has calculated that it sent 70,000 tonnes of waste to landfill in 2004. In 2010 it is planning to cut that to zero. Not so much as a teaspoonful of sawdust. And according to chairman Paul Drechsler, this is not so much a question of pain as gain. He says: “You can moan that there is this huge mountain of waste, or see you can see it as a tremendous opportunity.”

The firm has made recycling part of its core business strategy and divided it into four areas. It has joined forces with WRAP to tackle the first two: working with its customers and supply chain to reduce waste; and changing the site behaviour of its subcontractors. The third area covers how the company needs to be structured to deliver its target, as well as what training is needed. Finally, Wates has set itself the goal of influencing the government on waste regulation and tax issues, and working with other major contractors, too.

Wates has begun its campaign by trying out waste minimisation techniques on live projects. The pilot for the company’s retail division was the £4.5m refurbishment of a Primark store in Maidstone, Kent, which had a typically fast-track programme of 16 weeks.

“One of the biggest challenges for any building project is space,” says Andy Fancy, operations director for Wates’ retail division. “We initially thought the only way to recycle was to segregate at site level. The other challenge was that I genuinely didn’t know what we could recycle.”
The answer was a product called a Hippo bag. These are large plastic bags that replace skips and are much smaller. Less space is needed for waste segregation, and a lorry can take away 10 at a time. Some of the waste went out mixed, but there had to be some segregation on site because demolition works and fit-out were taking place at the same time.

Thanks to the Hippo bags, Wates managed to recycle 95% of waste on the site, which equates to 600 tonnes of materials. “We would have achieved 100% if we hadn’t spilt paint over some timber,” says Fancy. He adds that the recycling cost £6,000 but that next time “it won’t cost anything”. The process will be fine-tuned on a second trial project, with the objective of rolling it out across the whole retail business next year.

A five-year Decent Homes project at Sandwell near Birmingham is a different animal from a quick retail scheme, however. Most of the waste on this project is composed of old kitchen units and bathroom suites, as well as associated waste such as partition walls. Steve Morgan, a construction manager, said site-based segregation was problematic because it would mean leaving skips outside people’s homes. There was also a risk of vandalism.

Morgan needed a waste transfer station that would separate and recycle the mixed waste. He eventually found a firm called AWL and was impressed by the sophisticated equipment it used. Like his colleague in Maidstone, Morgan liked the Hippo bags as they could be placed right outside the property being stripped.

More than 90% of the waste produced on the site is being recycled. Morgan has worked hard to get to this figure – he asked AWL to identify exactly what was going to landfill so he could see what still needed to be tackled. Plastic baths are a problem because the only company that can recycle them is in Holland. Wallpaper was also difficult because it had glue and plaster stuck to it, but a company has been found that can turn it into egg boxes. Morgan has even found a way of recycling the Hippo bags, which can only be used once. A firm shreds them and turns the plastic into rope, which Morgan buys to use on the project.