What is the cost of our built environment?

Building and engineering professionals have over the last 150 years become proficient at determining costs of projects that clients have desired be built. Whether it be a hydro-electric dam, a power station, bridge or chemical manufacturing plant, based on detailed designs such projects have been broken down into small elements and the cost determined.

Over the last few years the consciousness of the need to consider sustainability in our activities has reached new heights, as environmental ethics have been incorporated within most professionals’ codes of ethics, and sustainability is becoming important to many individuals. This increased awareness has taken place contemporaneously with a reduction in professional input towards the construction of buildings, along with a New Zealand Building Act which requires a specified intended life of buildings to be at least 50 years (and similar in some other countries). This specified intended life could be seen as incompatible with the notion of sustainability, considering that many existing buildings in other countries are centuries old.

On the face of it, there appear to be contradictions in this New Zealand Building Act (arguably) minimal specified intended life requirement of buildings due to many competing issues in the present highly commercial world.

The term sustainability may conjure up many different meanings to different people. It generally implies, however, that something should last for as long as possible so that it does not become prematurely obsolete. This should imply a positive impact on the mortality of a country’s building stock, so that buildings last longer before they have to be maintained and replaced. Since the actions of each individual affect the earth in some way, it must be kept in mind that building activities must not be considered in isolation. With in excess of 60,000 chemicals in common use and pollution paralleling technologic advances, increased pollution (that is anti-sustainable practices) is related to “the production and use of energy, the production and use of industrial chemicals …” (Plaa, 1998). The production of building materials is intrinsically linked with these processes.

Reflecting on the UK building scene, Addleson (1977) stated that shortcomings in buildings owing to a proliferation of new materials and building techniques became prevalent in “the post-war period”. He questioned “the significance of the sixty-year economic life of buildings”, suggesting that they could be beyond their economic life before then.

Does the concept of “expected life of buildings” sit well with society’s current expectations relating to sustainability? The proven ability of New Zealand houses to exceed a service life of 140 years seems to throw into serious question why such a relatively short specified intended life is allowed under the Building Act (Johnstone, 1999). From the writer’s experience in the building industry, it has become apparent that this situation is leading to planned obsolescence, with many developers intent on meeting the minimum statutory requirements (or even less, if they can get away with it), for maximum profit, without considering any other adverse matters relating to environmental issues or other social issues.

The term sustainability usually implies in a general sense the wise use of resources. This can have many different meanings and interpretations. Not enough consideration is given to the energy embodied in existing buildings; instead, there is too much emphasis on new development of housing (Seip, 1979). Few buildings are ever demolished as a result of failure of their structural system. Johnstone (1994b) advised that “Departures of dwellings from a housing stock are the end result of an economic process and the potential physical life of most dwellings is not realised”.

The lowest first cost is also a driver for developers in order to maximise profits at the expense of appropriate life cycle considerations.

The question of the ethics of so-called sustainability was raised by Buckeridge and Tapp (1999). They questioned society’s morals in emphasising the words rather than effectively dealing with the issues, and suggested that the road towards sustainability is even being thwarted. This feeling appears to be borne out from the preceding discussion. According to The Institution of Structural Engineers (1999), “Sustainable development is for all cultures, climates and geographical locations and for all disciplines”. This is an interesting concept considering that most “developed” countries plundered their forests, sometimes, centuries ago, and when China, for instance, representing a quarter of the world’s population, is at the very early stages of its “modernisation” programme. Challenges like these are yet to be addressed by anyone (Walls, 2000).

Given the devastating effects of the recent earthquake in Haiti why should they even think about “sustainability”?

The sustainability of buildings is strongly linked with durability, a notion which is not even covered by building codes in many countries. In many areas the path towards sustainability does in fact appear as being thwarted. “During the last 50 years, buildings in general, and city buildings in particular, have become significantly less, not more, durable and much more resource consumptive”. (Storey and Baird, 1998). Most of this derives from expedient practices motivated by short-term commercial (monetary) gains.

Porteous (1992) advised that in New Zealand there is no nationwide system of investigating and recording events of building failure. This is likely to apply to all countries. It is unlikely also that any country has compiled a database of age-specific dwelling losses (Johnstone, 1994a). In order to practise sustainable living in a serious way, it is important that all the information tools available are implemented. Without those two knowledge databases in place on an ongoing basis, and without dealing with the issues covered in this posting, then it can only be said that society is paying lip service to the notion of sustainability.

REFERENCES

Addleson, L. 16 Feb 1977. “Guide to Building Failures”. Architects Journal. pp 23 - 25.

Buckeridge, J St J S, & Tapp, B A. 1999. “Ethics and that Ethic Called Sustainability”. Australasian Environmental Engineering Conference. Auckland, New Zealand.

Johnstone, Ivan M. 1994a. “Modelling the annual replacement rate of housing stock”. Fourth Australasian Real Estate Educators’ Conference. The University of Auckland. New Zealand.

Johnstone, Ivan M. 1994b. “Modelling the Dynamics of Housing Stock”. Department of Property. The University of Auckland. New Zealand.

Johnstone, I M. 1999. “Periodic Rehabilitation and Reductions in Total Average Costs to Sustain Dwelling Services”. Department of Property. The University of Auckland. New Zealand.

Plaa, Gabriel L. 1998. “Introduction to Toxicology: Occupational & Environmental”, in “Basic & Clinical Pharmacology”. 7th Edition. Bertram G Katzung (ed.). Lange Medical Books/McGraw-Hill. San Francisco.

Porteous, W A. 1992. “Identification, Evaluation and Classification of Building Failures”. PhD thesis. Victoria University of Wellington. New Zealand.

Seip, H. March/April 1979. “Building in Economic Terms”. Building Research and Practice. p. 90.

Storey, John B & Baird, George. 1998. “Towards the Self-Sufficient City Building”. IPENZ Conference. Auckland. New Zealand.

The Institution of Structural Engineers. 1999. “Building for a sustainable future: Construction without depletion”. The Institution of Structural Engineers. London. England.

Walls, Kelvin. 2000. Review of “Building for a sustainable future: Construction without depletion”. The Institution of Structural Engineers. 1999. London. England. For IPENZ “e.NZ Magazine”, Sept/Oct 2000.