Home buyers, and some real estate developers, are realising the impact of subdivisions on the environment and are looking at ways of minimising the environmental harm from building new. The movement to protect the environment (global and local) is also being led by enlightened local bodies which enact bylaws to meet Low Impact standards.
In Great Britain is this Stoneham Green affordable housing development near Southampton which, Green Building Press reports, is one of the UK’s first to achieve Code for Sustainable Homes Level 6 because of its utilisation of Biomass digesters amongst other energy-saving techniques. The focus here is on energy conservation. Other developments stress different benefits of sustainability.
What makes a dwelling Low Impact?
Before we can establish laws for sustainable, low impact housing we really need to understand and define what we are talking about. ‘Sustainable’ and ‘Low Impact’ are such easy words to throw around, especially when they refer to houses or buildings, but it is vital that the same definitions are held in everyone’s head.
A survey of definitions throws up a range of yardsticks used to measure Low Impact Dwellings, both in how they physically affect their surroundings to how they affect the people who live in them,
Simon Fairlie definition
Low impact dwellings (LID), in the UK sense of the term, was described by Simon Fairlie, a former editor of The Ecologist magazine (*1), in 1996 as: “development that through its low impact either enhances or does not significantly diminish environmental quality.” (*2)
For Simon Fairlie: living the good life gave him a clearer perspective of what is meant by ‘Low Impact Development (LID)
Fairlie later went on to study the ‘green’ assumptions of diet when he wrote a book ‘Meat: a Benign Extravagance’, in which he challenges conventional thinking about the sustainability of the vegan and vegetarian diets. He claims we ignore the high impact on resources necessary (and travel distances required) to gather vegan/vegetarian food and that feeding animals on waste food production could have less impact on the environment.
During his time with The Ecologist, Fairlie wrote: “Neither the term (Low Impact Dwelling) nor the concept was new. People have been living low impact lifestyles in low impact buildings for centuries; indeed until very recently the majority of people in the world lived that way.” (*3 ) In 2009 Fairlie revised his definition of a LID as: “development which, by virtue of its low or benign environmental impact, may be allowed in locations where conventional development is not permitted.” (*4)
Does low impact require fewer restrictions?
He explained: “I prefer this revised definition because wrapped up in it is the main argument; that low impact buildings need not be bound by the restrictions necessary to protect the countryside from ‘conventional’ high impact development a.k.a. suburban sprawl. There are two other principle arguments in favour of LID:
- (i) that some form of exception policy is necessary because conventional housing in a countryside protected from sprawl becomes too expensive for the people who work there; and
- (ii) soon we will all have to live more sustainable low impact lifestyles, so pioneers should be encouraged.” (*5)
The LID connection with land
Others have expanded on the definition. A study by the University of West England (*6) acknowledged that: “LID is usually integrally connected with land management and as much as describing physical development, LID also describes a form of livelihood.” (*7) However, it also states that as LID is a “multi featured and intrinsically integrated form of development,” a simple definition cannot capture the meaning of LID and goes on to develop “a detailed themed definition with detailed criteria.”
No simple definition of Low Impact
In 2013, Dr Larch Maxey (*8) held the main features of LID to be:
- locally adapted, diverse and unique
- based on renewable resources
- of an appropriate scale
- visually unobtrusive
- enhances biodiversity
- increases public access to open space
- generates little traffic
- linked to sustainable livelihoods
- co-ordinated by a management plan
Government commitment to Low Impact Dwellings
Already European countries, perhaps faced more obviously by the results of decades of disregard for the environment, are looking at options for low impact development. For example: all new homes in the UK are to be carbon-neutral by 2016
Low Impact must reach beyond buildings
In New Zealand, Claire Mortimer, Landcare Research November 12, 2010, posed the question: “Can we design cities to cleanse urban waterways and increase NZ’s biodiversity? Low Impact Urban Design and Development (LIUDD) is an approach which works with nature, using design features such as rain gardens and green roofs to reduce pollutants entering urban streams and harbours, while creating green spaces for NZ plants and animals to live in and green spaces for people to enjoy.”
This concept acknowledges the role many plants play in neutralising or filtering excess pollutants from waste water. While green roofs are catching on in other parts of the world (e.g. France where laws insist new houses must have either solar or rooftop gardens), in areas where water is captured for household use in holding tanks a green roof is not practical. We also have to decide if the green roof is sustainable – will people maintain the roof garden without coercion?
Sustainable water systems
With environmental warming extreme weather patterns are hitting every country. Even in our area in Golden Bay we experienced such an event. Water is very powerful and can cause unimaginable damage – and this is an area where roof water is captured in household tanks.
Can you imagine how much worse the damage would have been without tanks to reduce the runoff?
The household water tank is a relatively cheap way of reducing immediate run-off in extreme weather events. However, systems for later disposal of used (grey) water are not so cheap, especially if the water is intended only for watering a vegetable garden. Roof captured water has fallen out of favour, in that we have come to believe it is full of impurities that must be removed. Just how much of that belief is related to location and how much to superstition is unclear. The Drinking Water Standards for New Zealand focus only on public supply and so strive for optimum absence of any level of pollutants.
So what are the differences in impact (health, environment and cost) between a water system that reduces or eliminates storm water run-off through tanks and water treatment on site, and one that simply removes the runoff from the house site and at the same time delivers treated water via another public pipeline?
And this is where we come up against the differences in definition – in Canada and the US the definition used to describe low-impact development is based in a planning and engineering design approach to managing storm water runoff, while in Britain the definition is used for developments which provide little or no environmental impact, such as the housing estate pictured above.
According to the New Zealand Centre for Sustainable Cities blog: “The fundamental principle of low-impact development is that it’s better – both for people’s pocketbooks and for streams – to prevent storm runoff than it is to treat it (the water). That means building green roofs and rain gardens, installing rain barrels and cisterns, and using porous concrete and pavers.”
To balance a healthy water supply with sustainability is a challenge. Mains supply requires regular maintenance and repair of many kilometres of pipes from a treatment source. Using individual collection puts the onus of treating and maintenance on that individual. An interesting table (though totally without data) is published on the Government Health Education website. The message seems to be for a sustainable individual water supply all you need is household bleach regularly administered.
New versus old
While our focus is on changing bylaws to allow new low impact sustainable developments, we cannot turn our back on helping owners of low value housing stock to lower their environmental impact. For many, the cost required to upgrade is beyond them for the very reason that they live in low value housing.
We cannot advocate for new development as a panacea for fixing the problems of sustainability. As a Landcare Research initiative discovered, “Retrofitting an existing old building is always a challenge. We worked with the family … to build their awareness and ability to manage the ongoing operational decisions involved with balancing energy and water cost savings with comfort and health improvements.” Nor can we ensure that new low impact designs will always house people who understand their responsibility in the process.
New Zealand construction and housing companies are catching on to the idea of ‘sustainability’, but it is hard to marry that with the cost of such a home.
Here are some New Zealand examples:
- Ekohome offers a range of affordable eco houses that have been specifically designed “to be flexible, sustainable and within the price reach of ordinary New Zealanders at just 5%-10% above the cost of a standard NZ home”;
- ebode “provides architecturally designed passive solar homes for New Zealanders”;
- The Zero Energy House company incorporates passive and solar energy, rain water collection and grey water disposal systems to reach its claim to zero energy.
However, if you look at their house designs, extravagance of space is an obvious issue. When these low impact houses must compete for buyers with extravagant house plans, as seen in some recent developments around Christchurch, genuine low impact houses such a Little Greenie will wilt in comparison. We have been sold the House Beautiful concept for too long. We actually need to question why we need so much space to live in – ourselves included!
Issues to be addressed
Any move toward sustainable housing development has to address:
- Education – landlords, renters, owners, local government and even MPs to make them aware of the economic and social benefits of low impact development
- Affordable access – are new low impact homes only for the middle-class?
- Building materials – why are the costs so high in New Zealand and should we import cheaper housing materials despite the social implications?
- Economic system – will the economic system of loans coming only from Banks at relatively high interest continue to put low impact development out of the reach of most New Zealanders?
- Maori (first people’s) values – has low impact development been ‘captured’ by European values / are Maori values being overlooked?
These questions are not posed for YES/NO answers; they are asked to generate discussion and to trigger some innovative thinking.
PDF academic research document on Providing Incentives for Low-Impact Development
Booklet on Low Impact Development from British perspective
By Heather Sylvawood