City Evolution - digital
Demolition and smart cities
Despite our building stock being our most important manmade resource it is estimated that we will throw away around fifth of it over the next 50 years.
Furthermore we will do this with no assessment of embedded socio economic value within these buildings other than for an estimated 7% of our stock on which demolition controls are imposed.
This rebalancing of processes has already begun in London, with a drop in demolitions and an increase in conversions leading to a faster rate of housing growth in the last decade than in the 1960s and 1970s.
However energy legislation is slowly changing both the construction industry landscape and our attitudes towards demolition. Over the past 25 years there has been a significant shift in construction patterns in Europe away from new build, towards the maintenance and refurbishment of existing buildings. This trend, accelerated EU Waste directives New technologies and 20% VAT on new build are also offering the possibility much more detailed tracking and analysis of impact of new build and refurbishment schemes on cities as a whole, both by scientists and researchers and by communities themselves. International ContextConstruction activities and processes are some of the greatest consumers of energy and materials at the global scale. High energy use required to support affluent lifestyles in developed countries require vast levels of extraction of natural resources required for new construction purposes and for the demolition and disposal of older stock. In the late 1980s and 1990s the need to predict levels of refurbishment for energy monitoring purposes, led to studies in most European countries assessing the likely survival rates of buildings stock. Today there is growing interest in building longevity and its implications building waste, resource reserves, building demand, material stock flows, retrofit and energy emissions. More information is however required on how we extend building lifespans and limit issues with methods and materials unbale to be repaired. why certain building morphologies have been able to be more adapt more successfully than others, over extensive time periods, and the extent to which these features can be mimicked and embedded in new energy efficient building designs. A range of issues relating to embedded economic and cultural values within the building stock are also being discussed. These include how we ensure each generation use of all forms of social, natural and economic capital do not exceed the possibility for their replacement , and the extent to which future stock can be engineered (Hassler 2009); how a decline in one type of stock can be compensated by an increase in other type of stock so that the economy’s aggregate capital is maintained? (World Bank 2012), and how we will support long term future stock being fit for purpose? urope: Estimated demolition and survival ratesUK contextIn London 2014 we can see a reduction in demolitions and increase in adaptations reflecting European figures. research. However a number of issues have , in the UK. The most detailed research carried out on the impact of demolition in the UK in relation to energy agenda has been undertaken by Anne Power at LSE. In her 2008 Paper ‘ Does demolition or refurbishment of old and inefficient homes help to increase our environmental, social and economic viability’ (2008) she sets out out key issues and potential solution relating to demolition, However in the UK many buildings are still being destroyed with little or no evaluation of their current or potential socio economic and environmental value, potential of older homes to outperform even zero carbon homes subject behavioural change was also put forward german home examples renovation. Empty homes EHA study of Embodies energy and energy in use of new build over 50 years showing embodied energy consititutes 35% of the total Co2 emissions for new build compared to &% for existing . In use built to 2002 standarsd was same as upgraded Victorian Working with a diverse range of bodies incuding the Empty homes agency, English heritage, Building Researcj Establishment , The Ryla Commisison on environmental pollution Power’s paper was written as the Pathfinder project, initiated in 2003 was underway, in which regeneration, energy reduction and fuel poverty arguments were used to justify the demolition of thousands of sound terraced houses in Northern and Midland cities. Though largely halted by community outcry and support by the conservation group SAVE, mass demolition was still being reported in the press in 2013 with assets considered by communities to be the key to regeneration long term sustainabilitybeing destroyed. http://www.theguardian.com/commentisfree/2013/mar/27/liverpool-rotting-housing-renewal-pathfinder. Power argues that in the rush to provide new housing and meet energy objectives represented not the opportunity for regeneration. She argues, as with the case of all elements of a thor away society, of the seeming ease with which policy makers see buildings can be removed and replaced but the reality of the slow, costly and unpopular nature of housing demolition. She argues the feasibility of raising the efficiency of existing stock to the level of new build, with new homes using 4-8 times more resources than the equivalent refurbishment , and that terraced housing and low to medirum rise blocks already has high desnsities needed for sustainable development. Demolition and building are by colume the biggest source of landfill in the UK there are also consideration sof transportation, toxicity and pollution in new materials. Power argues that it is essential to plan for housing ‘on th basis of supply and energy calcualtions without including he social and economic roles of housing, risks missing links between family facilities schools transport and jobs. Seen in DCLG report of rare cases of new w towns becoming self sufficient , and that large scale cheap housing iften produced lowest common denominators estates. Increased demolition figures of 3 million dwellings to ger rid of ; leaky homes’ 60% reduction in energy and whole scale demolition projects, lack of embodies carnon counted inew homes impact, does not take account of how materials actually last , as sresources get shorter need much higher energy efficiency standarsd and epair stock as , initiated by John Prescott was demolishing thousands of sound older terraced houses in the north of England. older houses in northern England deshe sets out in detail the many issues raised by demolition of the building stock. She argues that throwing away material objects is harmful to the environment, wasteful in term sof energy and materials, and carefless in terms f diminishing , not only in terms of energy but in the impact .