Type search for do it yourself home improvement
DIY, gardens, home tips >
When building green, changes aren't just to be made in the materials and design of a building. The UK generates 29 million tonnes of municipal waste each year of which 87% comes from households. Most of this waste ends up in landfills with only 19% being recycled. About 5 million tonnes is packaging of all sorts, some of which is recycled, and 7 million tonnes is food waste, very little of which can be reused.
Integrating recycling and waste management into a new building or estate will create a mindset geared to preventing environmental damage.
This can be achieved at the time of designing a building allowing for recycling containers such as separate recycling bins and compost heaps.
Recycling materials will always involve separating them into similar piles of rubbish. The most common recyclable materials thrown away in household rubbish are paper, plastics, some metals (aluminium, steel) and organic waste. Providing areas in a building into which separate bins can be stored as well as easily accessed will encourage the occupants to recycle, making it feel an essential part of day to day life.It has become a ritual and an easy feelgood action that will supposedly 'save the planet''. Every little helps, but in the UK, recycling is largely irrelevant as the main climate change factor is a very high and increasing level of energy use.
Kerbside recycling is available to 79% of the UK population and has been found to be more efficient then "bring" sites (bottle banks etc.) providing one tonne of recycled material for 14Km of road mileage (bring sites in comparison require 271km per tonne). It should be noted however that kerbside collection is often not available in rural areas, and when building in such areas, consideration should be given to how waste can be transported effectively and easily.
Using recycling bins with removable sturdy collection boxes will save the occupants the potential inconvenience and mess of bags. Fortnightly rubbish collections increases recycling but is very unpopular.
Paper is probably the easiest material to recycle and makes up 18% of the total average household waste. Paper accounts for 43% of the worlds harvested wood usage. Around 95% of all household paper is suitable for recycling one way or another. Paper recycling uses less energy than producing fresh paper. The savings in energy and emissions can be huge, around 28-70% less energy and over 90% fewer emissions. Recycling papers saves on trees being cut down. The amount of water used is far less then in creating fresh paper. Recycling one tonne of copier/printer paper will save around 2 tonnes of fresh wood from being required,
Recycling paper that is thrown out also has the advantage of taking it out of the landfill waste system. A tonne of newspaper recycled not only reduces the need for fresh wood by a tonne but also removes a space of 3 cubic meters from the landfill which it would occupy. Paper and other waste in landfills also decompose over time, releasing methane, which is a highly potent greenhouse gas and major contributor to climate change. Whilst newer land fills have methods of recovering methane for use as biogas it is still a huge environmental saving, taking paper out of the system and producing less methane.
District Combine Heat and Power systems could take waste paper burning it to produce electricity and heat. Whilst this produces carbon emissions the trees used to produce paper will have removed CO2 during there life negating some of the emissions. This is only really suitable for very large developments although some forms of domestic heating systems can use paper as fuel such as wood based fires and boilers.
Recycling paper has some drawbacks. It can only be recycled a maximum of 6 times before the fibres contained within the paper become to short to be reused. When this point is reached virgin material can be added allowing the paper to be made from a percentage of recycled material. When considering a build, space should be created to allow a paper-only bin to aid recycling.
Glass is a commonly used household material. Bottles jars and other forms of glass account for 3.6 million tonnes of waste each year (around 7% of the total household waste) with only 752,000 tonnes being recycled. Unlike paper glass can be recycled indefinitely with no loss of quality or strength. Glass can either be recycled or reused with recycling popular in the UK and reuse in European countries such as Austria and Denmark. Recycling involves collecting the glass and crushing it down. The crushed glass mixture is then heated in a furnace to melt it down and recast into the new containers etc.
Using recycled glass saves on raw materials required and reduces carbon emissions (around 300kg of CO2 for every tonne recycled). Recycling glass has a few drawbacks. Often containers such as jars and bottles have elements that must be removed before recycling can take place (lids, foil etc.) and this often has to be done by hand which can be quite labour intensive. Colour is also an issue with recycled glass. It is very hard to make recycled glass as clear as fresh glass, reducing the applications it can have in the packaging industry.
Reusing glass is an even more energy efficient use of waste glass than recycling as it requires only a tiny bit of the energy involved. This process involves the manufacturer collecting used bottles to wash out and refill. This is popular in areas such as Denmark, where 98% of all the bottles used are returned by customers to a manufacturer to refill. In poorer countries such as India and Brazil bottles are returned to keep costs down. It is far cheaper to reuse a bottle than it is to recycle it. When designing a build a recycled glass container of some sort should be built into the design. Ideally this should be stored externally as glass is bulky and can be dangerous when broken up.
Metal from household waste currently enjoys a high level of recycling in the UK. The two most common forms of metal household waste are aluminium and steel cans, which together make up around 3% of the total household waste. Both aluminium and steel can be recycled indefinitely with no loss of quality or durability.
Aluminium is produced from a mineral ore called bauxite. Bauxite is mined from various locations around the world and requires shipping to move it to and from factories adding CO2 from transportation as well as ecological damage associated with mining (water table pollution, loss of native habitats etc.
Recycling aluminium cuts the amount of bauxite used dramatically. 1kg of recycled aluminium will save 6kg of bauxite and 4kg of chemicals used in the processing of fresh aluminium, and around 15KwH of electricity. When recycled aluminium only requires 5% of the energy and therefore releases 5% of the CO2 than the same amount of fresh aluminium.
Steel is produced from iron ore, which although plentiful does require mining and transportation. In order to create steel the ore is heated in a furnace using huge amounts of energy and releasing carbon dioxide. Recycling 1 tonne of steel will save 1.5 tonnes of iron ore, 0.5 tonnes of coal and 75% of the energy expended in production. Steel is one the easiest material to sort for recycling, as it simply requires a magnet, which will pull steel from out of the mixed waste.
While separate sorting bins for steel and aluminium cans are not as essential as separating other materials for recycling (I.e. paper and plastic) it is preferable that they both have separate bins to ease the recycling process.
Plastics are used in many household goods and packaging. Currently 4.7 million tonnes of plastic products are used each year, accounting for nearly 3 million tonnes in plastic waste each year. Plastic poses a number of problems environmentally. The first is that it does not biodegrade easily, often taking hundreds of years, which will be spent taking up space in a landfill. Plastic uses many materials in its production that harm the environment such as oil (accounting for around 7% of the world's oil use) and requires a lot of energy in manufacture. Plastics also come in many different forms. Up to 50 types of plastic are present in the household waste stream each requiring different methods to recycle.
When considering building plastic recycling into a building design it may be necessary to cut down on the amount of recyclable plastic anticipated. For example providing resources to recycle plastic bottles will mean that only three types of plastic will be present making it easier for occupants to sort. Plastic bottles account for around 40% the total plastic waste from a building so significant gains can be made, while not baffling occupants trying to establish which plastic goes where.
See our chapter of Bottled Water which has shocking statistics about bottles just from that sector.
Organic waste such as food waste can also be put to better use than sending it to a landfill. Kitchen waste accounts for 17% of the average household waste, with garden based waste taking up a further 21%. Building into the design an area of the garden that can be used as a compost heap will allow food waste to provide an excellent natural fertiliser.
Systems can be built into greywater recovery systems to further reduce the amount of organic waste, such as reed bed filters which remove pollutants and some organic wastes purifying the water naturally.
Water can be recycled. Used domestic water is called greywater, and the toilet waste is called blackwater. Greywater recycling schemes are recommended. Blackwater has to go into the sewerage systems under normal conditions. To recycle locally, a special plant has to be built to use it which might suit a large estate.
Textile waste accounts for 3% of the waste from an average household. This includes things such as old clothes, shoes and rags used for cleaning. By providing sorting bins old clothes can be sent to third world nations for disaster relief and non-wearable fabrics can be recycled. This can involve shredding them and using them for things such as insulation and padding or fibres can be reclaimed and used in the production of new garments.
Batteries used in home and automotive applications can pose numerous problems to the environment due to the chemical their make-up including heavy metals such as mercury that can poison water tables if disposed of incorrectly. Household batteries contributed 19,000 tonnes of waste in the year 2000.
The metals used in the production of batteries can be reclaimed for use in batteries and other products. With the average UK household using 21 batteries a year a separate battery bin is not necessary and there is little that can be done on a single building. However where a large construction project such as a housing estate is being considered a central depository for batteries should be included.
Various freepost systems are around to prevent dangerous chemicals from batteries getting into normal waste, but there is a very low awareness of these.
All Dixons, Currys, The Link & PC World, and Sainsburys, and some libraries have a battery collection point.
Incidentally low energy bulbs contain a lot of mercury and should be recycled by sending back to the manufacturer.
Biogas and integrated recycling
On larger projects such as housing estates consideration should be given to harnessing the methane produced by decomposing organic waste. A centralised composting scheme could not only create fertiliser but also bio-gas however such schemes are only suited to major developments as home based systems will require a lot of space and may produce unpleasant odours.
When building large developments community based recycling programs can have a huge impact. Other common forms of waste can be put to good use. Computer and electronic waste which normally contains some toxic materials can be deposited centrally and redistributed either to charities or sold on at a budget price to generate revenue instead of being sent to the land fill.
Similar systems can be put in place for plastic toys and other plastic products. To recycle the materials used items will need to be taken apart in a time consuming process. By redistributing the item, say to charity, time and money are saved in taking it out of the land fill, as well as saving making a new one.
Recycling provides huge savings in the cost of raw materials as well as the carbon emissions produced. Recycling is one of the most efficient weapons against climate change and is also enjoying heavy support from governments seeking to reduce the amount of waste going to landfills.
Considering recycling at the design stage of a new project, be it a small house or a whole estate, can remove some of the inconvenience occupants often claim prevents them from making the effort to recycle. Continuing investment in recycling and more education will help to reduce our impact on the planet.