1. 16469 Low Energy Building Design Sustainability – an overview
Dr Nick Kelly
ESRU

2. This Class
the basis of this class are the principles of sustainability
but what are these?

3. Class Activity
in the context of buildings what does sustainability mean to you?
get into a group of 4 and produce 5 bullet points that encapsulate your understanding of a sustainable building

4. Sustainability in Buildings
“Sustainable building design should aim to provide a balanced solution, offering optimum working/living conditions, alongside reduced environmental impact, both now and in the future. Taking the complete building lifecycle into consideration, there are many factors involved, from the location of the building, its design, subsequent operation and maintenance, to the construction materials and practices used, and how any future changes of use are addressed.”
D. McLean (IET)

5. Origins of Sustainability
Stockholm agreement (1972) addressed environment, economic and social development and outlined 26 principles for sustainable development .
Brundtland Report (1987) defined Sustainability as:
"Sustainable development is development that meets the needs of the present without compromising the ability of future generations to meet their own needs"

6. Origins of Sustainability
"Sustainable development is development that meets the needs of the present without compromising the ability of future generations to meet their own needs“
as Engineers and Architects how does this apply to our activities?

7. UK Implementation
The UK government has published its guiding principles with regards to sustainability
Covers much more than just energy and natural environment
economy and employment
social justice
communities
etc.

8. UK Implementation 1 4 2 3

9. UK Priorities FOUR key areas:
sustainable consumption and production [1,2]
climate change and energy [1,2]
natural resources [1]
sustainable communities [4]
ALL of these areas relate to the built environment

10. Consumption
the built environment is the largest final energy consumer
in the built environment 40%3 of the energy consumed is used is for space heating with most heating systems running on natural gas
overall energy consumption is on the increase with a 19% rise in the domestic sector and 17% rise in the services sector since driven by:
demographics (increasing # of households 18.6M – 24.2M )
comfort expectations (average internal temperatures have risen 5oC since 19705)
lifestyle (multi-source lighting, increasing use of electrical appliances)
sustainability necessitates controlling energy demand without compromising on comfort and health
Sources 1 DUKES 2005, 2 NS Social trends 3 Energy consumption in the UK 4 NS Social trends, 5 domestic energy fact file 2001

11. Production
the domestic sector alone accounts for 28%1 of final energy consumption and 42 million tonnes of carbon (MtC) per annum2
UK-wide buildings accounting for over 40% of all UK carbon dioxide emissions, and with as many as 140,000 new homes needed each year it is no surprise that reducing these emissions is currently a key focus
improving energy efficiency has been identified as being the cheapest, cleanest and safest way of doing this
renewables alone DO NOT reduce energy consumption but can reduce electricity taken from the grid and the use of fossil fuels
sustainability necessitates maximising our use of renewable resources in the energy supply to buildings
Sources 1 DUKES 2005, 2 NS Social trends 3 Energy consumption in the UK 4 NS Social trends, 5 domestic energy fact file 2001

12. Resources
In the construction industry consumed over 420 million tonnes of materials
83% was primary materials
the construction industry accounted for around 80 million tonnes of waste per year (4 x domestic waste)
the resource efficiency is 63%
the day-to-day operation of buildings also consumes significant quantities of materials inc. treated water
sustainable buildings should use less raw materials in their construction and produce less waste – through the use of re-cycled materials and re-cycling of waste, re-cycled aggregates, insulation materials, etc, use of ‘grey’ water, etc
Source: The Construction Industry Mass Balance: resource use, wastes and emissions R A Smith, J R Kersey and P J Griffiths

13. Community
the UK’s sustainable development priorities also include the need for sustainable communities – covering the social aspect of buildings
sustainable communities should be:
environmentally sensitive - providing places for people to live that are considerate of the environment.
well designed and built
well connected - with good transport services and communication linking people to jobs, schools, health and other services

14. Legislation
also remember that new legislation is emerging that forces designers to include sustainability:
legislation, specifically related to sustainable buildings includes
Home Energy Conservation Act
London Energy Strategy (using planning powers)
Local planning regulations
Energy Performance in Building’s Directive (energy performance and renewables)
New building regulations (energy performance and renewables)
Sustainable Building Codes (England)

15. Class Activity (revisited!)
get back into your group of 4 and revise the 5 bullet points that encapsulate your understanding of a sustainable building

16. Achieving Sustainability
…. so sustainability in buildings encompasses a multitude of factors but how can we achieve it?
energy use
occupants
resource use
transport
sustainabiltiy
renewables
emissions
local community
waste and recycling

17. Measuring Sustainability
how can the resulting ‘sustainability’ of a design be assessed?
single or multiple metrics?
UK government currently has 127 indicator measures and 68 indicators on sustainability
not all relate to buildings

18. Performance Metrics

19. Performance Metrics GHG emissions energy consumption
renewable electricity/heat
resource use (water/fuel)
road transport
waste/recycling
air Pollutants
land use …
community participation
employment/poverty
education

20. Performance Metrics
BREEAM is a very common voluntary sustainability assessment method for buildings in the UK (LEED in the US)
buildings are scored based on information entered into a spreadsheet
outcome is a sustainability ‘score’ %
a systematic way to ensure that a broad range of sustainability issues are considered at the design stage
however BREEAM does not allow us to predict the likely sustainable performance of a building and it is not a measurement!
to do this we need to develop models and then simulate performance

21. Performance Metrics

22. Modelling Sustainability
to get a more robust measure of the likely sustainability of a building design we need to simulate the likely performance
we use a mathematical model of our building with boundary data to simulate performance
there are a range of simulation tools available to let us do this for buildings
NB to judge performance we need to compare performance against a reference (base case or bench marks)

23. Modelling Sustainability
Boundary data
Building Design
Mathematical Model
Performance Data

24. Modelling Sustainability

25. Modelling Sustainability
e.g regs house vs passivhaus

26. Modelling Sustainability
e.g regs house vs passivhaus

27. UK Implementation 3

28. This Class
in this class we will focus predominantly on sustainable energy issues
providing a comfortable, healthy environment for the building occupant whilst minimizing our use of finite resources
to achieve this our decisions will be informed by performance data and best practice

29. Postscript
even simulation and modelling will not tell us exactly how a building will perform
ALL modelling results are subject to error and uncertainty
ultimately the only way to truly gauge performance is to measure it in the actual building
…. however using a scientifically robust design process can improve the eventual sustainable performance of our buildings