Types of Construction and Demolition Waste
Construction and demolition waste covers a wide variety of materials, some of which can be recycled and some of which is considered hazardous and needs specialist handling. As with all commercial ventures, the construction and demolition industries have a duty of care to keep waste production down to a minimum and recycle as much as possible.
The construction and waste sector is actually one of the most successful when it comes to making sure that waste is recovered and recycled as much as possible. Some UK companies have been able to do this for 90% of the waste produced in certain circumstances, significantly higher than across other areas of the EU.
The Environmental Agency splits construction and demolition waste into the following categories:
Insulation and Asbestos Materials
Asbestos waste has been one of the biggest problems in the construction and demolition industry in the last thirty years because of the danger that it poses for the environment and human health. Most buildings nowadays have an enormous amount of insulation from the cavity wall and roof that needs to be processed.
Concrete, Bricks, Tiles and Ceramics
A large part of demolition waste comprises of concrete and bricks and fortunately our recycling rates of these materials is often much higher than with other general waste management. The reason is that most of this waste is non-hazardous and easily processed in recycling plants by either breaking down or reusing materials such as bricks.
Wood, Glass and Plastic
These materials have long been recycled and reused in other waste streams and most are non-hazardous, though wood, glass and plastic that has been treated with harmful chemicals needs to be handled differently. Wood can be used for other building jobs or cut down and transformed into biomass material. Glass can be melted down and turned into new windows, jars and bottles. Plastic, which has many different varieties, can be more problematic but can still be recycled.
Bituminous Mixtures, Coal Tar and Tar
This includes a range of products including those used for roads and driveways as well as flat roofs. A number of types of tar and bituminous mixtures have a hazardous component and need to be disposed of safely. Bitumen is essentially a binder that is used in products like asphalt and sheet material.
Metallic Waste Including Cable
Metals such as aluminium, steel and copper are considered as non-hazardous waste. This kind of material also includes products such as cable which contain useful amounts of metal all of which needs to be extracted during the recycling process. There is some waste that is deemed hazardous such as those products that contain or are coated with toxic substances.
Soil, Contaminated Soil, Stones and Dredging Spoil
One major area of demolition and construction is the effect that it has on the surrounding ground. Disposal can include something as simple as clearing stones to dealing with contamination of the soil. A particular type of this kind of waste is dredging spoil. When channels have to be dug or dredged, it can produce a large amount of soil that may need to be treated or processed by a specialist service.
Gypsum is widely used in the building industry and blocks can be found in boards for walls and ceilings. Gypsum sometimes contains hazardous materials but any non-harmful product can be recycled into new gypsum that can then be put back into the industry. It is a versatile material and is used in a wide range of other products such as fertiliser.
Another big part of the construction and demolition industry is, of course, cement which is used in foundations and for other parts of buildings. Un-used or unset cement is considered as a hazardous product and needs to be disposed of accordingly. Demolition concrete can be crushed and used as aggregate for building roads.
Paints and Varnishes
Unless they contain only organic solvents, most paints and varnishes have a hazardous component. From the varnish that goes on your skirting board to the paints used for ceilings and walls, the construction and decorating industry produces a large amount of this kind of waste.
Adhesives and Sealants
On a smaller scale, the construction industry also uses adhesives and sealants for areas such as kitchens and bathrooms and most of the waste disposal centres can handle packaging and left over product. That not only includes the actual contents and residue but the containers as well.
The construction and demolition industry has a pretty good record for recycling compared to some other waste sectors. During construction for the 2012 Olympic Games much was made of the fact that 99% of the waste produced during building was recycled. Many businesses often do this onsite and are becoming more adept at making sure that little goes to waste. For the demolition industries this may well be more difficult with hazardous products such as asbestos that need specialist handling. Materials such as concrete, bricks and metals, however, are more readily recycled back into the construction and other industry.
Find out more about the management of construction and demolition waste.