Where and How They Should Be Disposed

The National Waste Report 2010 defines construction and demolition waste as:

According to a report commissioned by the Australian Bureau of Statistics, the construction industry represented 31% of the total waste generated during 2009-10, with over 16.5 million tonnes sent to landfill. Because of these statistics, it is becoming increasingly more important for the construction industry to practice reuse and recycling.

During a construction project, there are a variety of commonly tossed materials that can be repurposed for other uses or used to enhance your project. Knowing what materials can be reused can save a great deal of money and will reduce the speed at which Australian landfills are filled. Large, heavy materials like asphalt, concrete and bricks incur high costs to dispose in landfill, so reuse becomes a more efficient and economic choice. Meanwhile timber and metal waste is valued highly, and often reclaimed for smaller projects.

Reusing materials in a new project will mean an inventory of current materials. Reusable items to add to your inventory include:

• Concrete and bricksDue to their relative weight and high disposal fees, masonry recycling is strongly encouraged. Reprocessing concrete involves a fairly standard crushing technique. Bricks can also be repacked as mixed masonry. Both are sought after in markets for low-grade all-weather road construction, pavement sub-bases, and other non-structural applications.
• AsphaltInterestingly, asphalt could be 99% recyclable, however in Australia our current best practice is for asphalt to include 30 to 40% renewable materials.
• MetalsMetal recycling is a lucrative, but fluctuating, market. In Australia 90% of metal waste comes from commercial projects, with steel accounting for about 95% overall. Magnets are often used to recover metals from general C&D waste.
• PlasterboardPlasterboard is highly recyclable. Unfortunately it is also considered a contaminate when found in other recovered waste materials. For that reason plasterboard recovery is often arranged through the supplier and the builder.
• WoodFrames, stairs, odd angle cuts, and small pet doors are all types of scrap wood that generally get tossed in the skip. But scrap wood can be ideal for small-scale projects and, at the very least, can be sold as firewood. As for hardwood such as beams, floor joists, posts, decking, weatherboards, sleepers, and logs can all be reused and cut down where required.
• LightsThere are endless ideas when it comes to reusing light fixtures and, believe it or not, old lights can be in high demand. The main materials of every light fixture tend to be brass, aluminium, or copper. Inside the fixture is plastic or rubber-coated copper wires. When separated, all of these materials can be recycled.
• Roofing materialsRoofs are generally covered with fibreglass composite shingles or asphalt. These materials can either be reused for the same purpose, or can be broken down into gravel and used on parking lots, paths and driveways. The leftover timber which makes up the framework of the roof can also be re-milled to make such things as cabinets and flooring. However, reusable roofing materials are not restricted to tiles and framing. Metal purlins, roofing sheets, sheet metal flashing, down pipes, valleys and gutters are all great materials for reuse. Any steel can also be shredded and blended with heavier gauge material, forming the base of an ideal product.
• ConcreteConcrete can be recycled and reused in a number of ways, but it all depends on how large the piece is and what shape it forms. Reclaimed concrete can be used in walkways, as a base for an asphalt pavement, or as a bed foundation in which to lay underground utilities. Old concrete can be recycled, crushed, and turned into aggregate - this, combined with virgin aggregate, can be used in new concrete. Other uses include pots, benches and paving blocks.
• Power points and switch faceplatesPower points and switch faceplates can be removed and reused or sold. Consult with an electrician or construction professional to ensure the product is safe for reuse.
• Soil and sandSoil, sand and other fine particles are best reused on-site or will require treatment or disposal.

• TimberHardwood timbers represent a significant market in the recycle and reuse industry. High grade Australian hardwoods could in the next 25 years run up to $1000 per cubic metre. Infrastructure timber, for example the timber that railway sleepers and power poles are made from, is also sought after in landscaping and furniture construction.
• Rock and excavation stoneSimilar to masonry, excavated stone and rock can be used in aggregate for pavement sub-base applications. Recyclability depends on the local geography and reclamation chain.
• PlasticsIn construction, plastics fall into two categories: durable and packaging. While plastics represent a significant amount of waste in C&D, current reports find that very little of the total is recycled. Despite this, there is an ongoing trend of improvement in the sector.
• DrywallIt’s commonplace to have sections of drywall that are too small for a complete wall, but drywall can still be used to patch holes. When kept free of moisture drywall keeps very well, meaning you can reuse it in a project down the track.
• GlassMost glass can be recycled. Windows and frames can be reused on a project or can be sold. As long as glass is intact, it can be cut down to fit a variety of other situations and, while it may seem like too much effort to keep such a delicate material, the cost savings associated with reuse can be huge.
• Doors, columns and mantelsAnything decorative and in good condition can be reused or sold for reuse. This includes doors, columns, mantels, fireplaces, handles and knobs. Be creative when salvaging materials and think outside of the box. Materials don’t have to be used in the same way; they should just be reused instead of thrown into landfill.
• AppliancesAustralians collectively own 45 million appliances and each year 2.5 million of them end up in landfill. Appliances are generally made up of two-thirds steel; it’s been known for more than 70% of discarded appliances to be used for scrap metal. Unfortunately, the other third contains hazardous substances such as lead, cadmium and flame-retardants, for which research is still being undertaken on how to best dispose of. Ideally, however, proper maintenance and reuse of the product is preferable where safe.
• CopperFor nearly 5,000 years, copper was the only metal known to humans. Nearly all copper mined throughout history is still in circulation. Its recycling value is so great that premium-grade scrap copper normally is comparative to 95% of the value of newly mined copper. Reusable copper includes pipes, fittings and electrical wiring.
• Plumbing fixturesOlder plumbing fixtures, such as taps, can contain lead solder and lead brass, which can leach into drinking water. Do not reuse plumbing or plumbing fixtures if it’s suspected they were installed prior to 1980. Consult a professional if you are unsure.