A key difference between humans and other species is the human ability to change and manipulate our surroundings. Usually this is done to support human existence as shown by medicine, transport and intensive farming. In order to maintain our future the next step is one of massive proportions, but not beyond human ability.
This next step is not just to maintain the rapid increase of scientific and human knowledge but to also do it in a stable way both environmentally and in terms of our actions to each other.
For home owners this does not have to mean turning your house into a wind farm or planting a forest in your back garden, it also does not have to be massively expensive or reduce the quality of life at all. If anything it can be quite the opposite with massive potential savings and health benefits. Major ways to reduce a house’s impact include:
- Solar panels- A 2.7 kWp system can generate around 50% of a household’s yearly electricity needs. The instillation is at only 5% V.A.T and a household can make £1,170 per year by selling excess electricity to the supplier! The payback time is 10 years.
- Solar Water Heating- Using solar energy as opposed to a gas or electric heater is a cheaper alternative to solar panels in terms of instillation costs but the return is lower. Savings range between £50 and £80 a year. The payback period differs as it may be possible to have the instillation costs partially paid for by the UK government.
- Wind Turbines- 40% of all wind in Europe blows across the UK and a small domestic turbine in the right position can generate £3,200 a year through selling energy back to the supplier meaning some systems have a pay back period of under a year!
- Loft Insulation- Insulating a previously bare loft can save the average household £145 a year with a pay back period of up to 3 years. By increasing the insulation from the minimum required by building regulations in new builds or conversions to 270mm the saving is £40 per year with a payback time of 9 years.
- Double Glazing- This is pretty much a standard in most properties now, but if a property still has single glazing, changing to double glazing can save £135 per year
- Pipe and Tank insulation- This is the cheapest efficiency measure to undertake with hot water tanks saving £35 a year and pipe insulation saving £10 both have respective pay back times of under 6 months and a year.
Draught proofing- An old front or back door is likely to be warped or badly fitted. this hole in your house allows cold air to come through and negate any other energy saving devices installed, the answer may be a replacement door.
- Cavity wall insulation- if not already present, this can save £110 per year and has a pay back period of under 3 years.
- Floor Insulation- This can save £50 per year and has a pay back period of exactly 2 years.
New Builds and Extensions
New builds can be built to be very energy efficient, with some houses which are carbon neutral and free of bills due to the use of renewable resources, but another factor to take into account is the impact of building the property itself. A big part of this is the “cradle to gate” energy used, this is the total amount of energy to extract, process and deliver the material to the site of the build. Click here for to see the embodied energy used for all building materials. For the lowest possible embodied energy it is best to use locally sourced materials such as local stone and timber.
Another factor in the over all environmentally friendliness of a material is how durable it is. Whilst lead may have a higher Embodied energy, a flat roof built from lead can last ten times longer than a bitumen and felt flat roof.
No matter what type of build it is, odds are it uses timber somewhere or another and there are a whole series of environmental concerns to go with it. The first of which is the sourcing, as said earlier the more local the better, however in reality it may not be possible to source certain types locally. There are schemes and groups which make sure that the timber is from controlled sources and does not cause de-forestation or damage to an eco-system. These groups include:
- FSC- Forestry Stewardship Council
- PEFC- Programme for the Endorsement of Forest Certification
- MTCC- Malaysian Timber Certification Council
- CSA- Canadian Standards Association
- SFI- Sustainable Forestry Initiative
All timber compliant with one of these schemes will be marked as such.
Another risk from timber is the chemicals used to treat them. An example is the most commonly used preservative Copper Chromated Arsenic (now banned) which is very toxic. Good builders like Marble can build to such a high standard that chemically treated timber use is decrease and only used where the ground conditions suggest there is a chance of damp. Alternatively there are non-toxic timber preservatives such as boron which are not harmful to humans or the environment.
The environmental impact of different types of insulation is based on a lot of different factors including it’s performance, the embodied energy and whether it releases harmful chemicals during it’s creation, use and destruction. See below for a description of each type.
- Cellulose is made from recycled newspaper and is ideal for lofts, it is treated for resistance to fire and rodents though contains no pesticides or other nasty chemicals which are common in other types. The manufacture uses very little energy as well which obviously greatly reduces the embodied energy.
- Sheep’s wool is obviously a renewable source and the minuscule amount of processing needed means it has a very low embodied energy. Other advantage include that it is not irritant like many other chemical based insulations.
- Hemp and Recycled Cotton combined forms a very efficient insulation with the same non-irritant qualities of sheep’s wool.
- Mineral Wool is a blanket term for Rockwool, glasswool and slag wool, the latter two being recycled material and the first being locally sourced but the embodied energy of all three is still much higher than that of previously mentioned alternatives.
- Polystyrene is a oil based non-biodegradable plastic which makes it useful for areas where this could be a problem, however it is toxic when burnt and can erode electrical cable coatings.
- Polyurethane is another oil based plastic which uses HFCs which are very damaging to the ozone. It is also toxic and irritant and has a high embodied energy.