Wednesday, 23 October 2013

PW 371-A EDITION 2.0 Government Specifications for Construction

PW 371- A and B EDITION 2.0 refers to the recently updated editions of construction works specifications developed by the South African Department of Public Works.  Specifications include:

  • Earthworks
  • Concrete Works
  • Masonry
  • Structural Timber
  • Structural Steel
  • Insulation, Sealants and Seals
  • Glazing
  • Electrical Works
  • Mechanical Works
  • External Works

The documents were published in July 2013 and can be accessed here. The update of the specification has been welcomed by industry and has received positive reviews. From a sustainability perspective however the new specifications do not appear to address sustainability in detail and there appear to be some gaps. These are described briefly below.

While the specifications mention of the need to consult to trade bodies such as TIASA on recycled content of insulation there is no reference to minimizing the use of insulation that contributes to global warming as a result of using CFCs and HCFCs as a blowing agent in manufacturing processes.  Sections on timber do not refer to any requirement to source timber from sustainable sources. There is also no reference to the origin of materials and components which is surprising given government's interest in promoting local content and localisation.

Electrical Works
Electrical works specifications do not include reference to energy efficiency measures such as efficient lighting, controls like daylight and motion sensors and monitoring capability in the form of sub-metering. In particular, sub-metering may be a very useful mechanism for improving energy management and accountability in government buildings and  could support energy efficiency improvements being driven by government through mechanisms such as energy performance certificates

Drainage, sewerage, water and gas supply, fire equipment, sanitary plumbing
This section of the PW 371 does not make reference to water efficiency aspects such as water harvesting systems and efficient taps, urinals, showers and WCs. The specifications include pit latrines but makes no reference to water efficient and ecological sanitation. Increasingly water is being seen as scarce resource and therefore many of the above measures should be included in specifications and are increasingly being addressed by municipal bylaws.

DEA Building: Highest Rated Building 2012/2013

The Green Building Council (GBCSA) has awarded the Department of Environment DEA's new building in Pretoria the Highest Rated Building 2012/2013. The building achieved 81 points and is currently in construction.

Gauge was the Sustainability Technical Adviser to DEA on the project and was responsible for the drafting the sustainability specifications that formed the Public Private Partnership (PPP) Agreement. This legal agreement included stringent sustainability criteria which has been reflected in the design and recognized by the GBCSA.  A previous post outlines aspects of the sustainability specification process.

The Year of Unprecendent Climate in African Cities

There is increasing evidence that greenhouse gases emissions are influencing our climate. To date, many of these changes could be described as 'precedented' or 'having occurred before in recent history'. The ‘precedented’ nature of these climate change events may be one of the reasons why global warming has not been addressed urgently, as these events are seen as part of the natural course of events. 

However a recent paper in the journal Nature draws on earth systems models  to show that in the near future the earth will begin experiencing unprecedented climate caused by global warming. Unprecedented climate refers to a situation where climate moves outside the range of historical precedent defined as a ‘shift continuously outside the most extreme records experienced in the past 150 yearsThis condition is shown in the graph below in red, with the blue and green areas indicating the first 3, and 11, years outside precedent. 

The paper goes on to plot specific dates for world cities when this condition will be experienced. In Africa this will occur in Nairobi in 2026, in Pretoria in 2043 and in Lagos in in 2029. This is shown in the figure below.

The dates listed in the paper are in the near future and have significant implications for the built environment that need to be considered and addressed. These include:
  • Local effects: Impacts of climate change will differ depending on location. Climate impacts such as flooding, extreme winds, drought need to be understood at a local level and local resilience and mitigation plans developed. Resilience and mitigation plans should consider sustainability (using for instance a framework such as the Built Environment Sustainability Tool (BEST))  and ensure that measures not only improve levels of local resilience but also sustainability. Gauge is also working on a resilience tool and integrating aspects of resilience into BEST.
  • Urban design and planning: Consideration of local impacts of climate change should be integrated into local development plans such as Integrated Development Plans (IDPs) and Spatial Development Frameworks (SDFs) to ensure that new development is appropriately located and resilient as well as strengthening existing area.
  • Buildings: Local impacts of climate change such as increased wind speeds and flooding should be reflected in more stringent building codes. This can be addressed through revising building regulations and national technical standards as well as through municipal bylaws. 

Monday, 21 October 2013

IARC: Outdoor air pollution a leading environmental cause of cancer deaths

A recent report from a World Health Organisation agency, the International Agency for Cancer Research has found that sufficient exposure to outdoor air pollution causes lung cancer. It points to research that shows that in 2010, 223,000 deaths were attributable to lung cancer caused by air pollution. While air pollution has been linked for some time to respiratory and heart diseases, the link to cancer indicates increased levels of risk. The agency identifies primary sources of outdoor air pollution as being from transportation, stationary power generation, industrial and agricultural emissions and residential heating and cooling.

There are number of implications for buildings of this report. These include:

  •  Heating and cooling of residential buildings: There should be a strong focus on passive design in residential environments. In particular, solutions should be found to ensure that the burning of coal and other fuels in and around houses for heating is avoided. Where fuel is burnt it should be burnt in a way that avoids risk of diseases. 
  • Transportation: There should be stronger requirements to separate vehicular environments from environments where people live and work. In particular, workplaces and residential areas that are beside highways and roads with large volumes of traffic should be evaluated. Measures to reduce vehicular pollution should be taken such as reducing congestion, using more efficient vehicles with, for instance, start-stop technology and electric vehicles and improving provision for public transport, walking and cycling.
  • Stationary power generation: There should be increased awareness about the risk associated with pollution from local petrol or diesel powered generators and stand-by generators. Where possible these should be avoided and renewable energy systems used.     
  • Guidelines: These findings should be reflected in guidance documents including the WHO Guidelines on Indoor Air Quality shown above. In particular it needs to be translated into practical measures that can be taken by Planners and Designers in urban areas and Architects in buildings. 

Saturday, 19 October 2013

Built Environment Capability for Sustainability

The World Wildlife (WWF) definition of sustainability as being the achievement of above 0.8 on the Human Development Index (HDI) and the achievement of an Ecological Footprint (EF) below 1.8 global hectares per person has a range of implications for the built environment (see Defining Sustainability). This definition is referred to as the EF-HDI definition.  These implications can be explored through the concept of built environment capability for sustainability.

Capability refers to the ability to do something, or the capacity to achieve a particular result. Built environment capability is therefore the capacity of the built environment to support the achievement of a particular result, such as the achievement of sustainability targets. This concept acknowledges that built environments, in themselves, are not sustainable or unsustainable. Even in areas where infrastructure has been carefully designed and managed for sustainability,overall sustainability performance can still be poor as result of users deliberately or unintentionally using this infrastructure incorrectly, or not using it all.

The concept of built environment capability is therefore not deterministic, and acknowledges human preference by affirming the importance of developing sustainable solutions that are preferable to prevailing or conventional solutions. This can be supported through high quality design and solutions which result in improved quality of life. 

Built environment capability confirms the pivotal role that the built environment plays in enabling, or precluding, human life and activity from becoming more sustainable. In particular, it asserts the ability of the built environment in enabling, supporting, and encouraging activities and lifestyles of occupants which are more sustainable.

Therefore in terms of the EF-HDI definition of sustainability, built environments can be described in terms of Ecological Footprint Capability and Human Development Capability.

Ecological footprint Capability
Ecological Footprint (EF) Capability describes the extent to which the built environment is configured and includes the characteristics required to support the achievement of ecological footprint targets as defined in the EF-HDI definition of sustainability. This capability therefore describes the extent to which the built environment supports required performance levels in areas such as ‘Food’,’Shelter’ and ‘Mobility’.

Human Development Capability
Human Development (HD) Capability describes the extent to which the built environment is configured and includes the characteristics required to support the achievement of human development targets as defined in the EF-HDI definition of sustainability. This capability therefore describes the extent to which the built environment supports required performance levels in areas such as ‘Education’, ’Health’ and ‘Quality of Life’.

Built Environment Sustainability Capability
Built Environment Sustainability Capability is a combination of EF and HD capability and provides an overall measure of the extent to which the built environment of an area supports sustainability.  Ecological Footprint Capability, Human Development Capability and Built Environment Sustainability Capability is measured in the Built Environment Sustainability Tool (BEST) and presented in figures and graphically in reports such as the one shown below.

Defining Sustainable Built Environments
Therefore, if sustainability is defined by the World Worldlife Fund (WWF) as the achievement of a maximum Ecological Footprint (EF) of 1.8 gha and a minimum Human Development Index (HDI) of 0.8, sustainable buildings must have the capability, or the required configuration and characteristics, to enable occupant populations to achieve these EF and HDI minimum standards. 

Are Sustainable Buildings a Constituitional Requirement?

The South African Constitution is widely recognised as one of the most progressive constitutions worldwide. It has a strong focus on human rights and the environment. This recognised through a requirement for reasonable legislation and other measures to be developed to ‘secure ecologically sustainable development and use of natural resources while promoting justifiable economic and social development’

This paper aims to understand the implications for the built environment of this statement through interpreting and expanding this into an explicit set of requirements for the built environment. The paper discusses these requirements in light of existing legislation and reflects on whether adequate measures are being taken in the built environment to implement and promote environmental aspects of the South African Constitution.

The review reveals that current building-related legislation only partially addresses the environmental and sustainability rights stated in the Constitution. The paper outlines a number of areas where legislation falls short of Constitutional requirements and makes some recommendations on how these gaps could be addressed.

Keywords: Built Environment, Constitution, Sustainability

Contact me for a copy of the paper.