A one day symposium on zero/low carbon sustainable homes took place at The University of Nottingham on the 24th October, 2012. The event offered professionals within the construction industry a unique opportunity to gain added and significant insight into the innovations, policies and legislation which are driving the construction of zero/low carbon energy efficient homes both here in the UK and elsewhere in Europe. It explored solutions to sustainability issues “beyond” the zero carbon agenda. BZCH followed on from the successful ‘Towards Zero Carbon Housing’ symposium the University hosted in 2007. This event is part of the Europe Wide Ten Act10n project which is supported by the European Commission Intelligent Energy Europe.

1. Beyond Zero
Carbon Housing
exploring solutions to sustainability issues
beyond the zero carbon agenda
2 4 th O c t o b e r 2 0 1 2 a t T h e U n i v e r s i t y o f N o t t i n g h a m
Department of Architecture and Built Environment

2. ©
Copyright Notice
A l l t h e m a te r i a l i n t h e s e s l i d e s
m ay n o t b e u s e d o r re p ro d u c e d w i t h o u t t h e
ex p re s s p e r m i s s i o n o f t h e a u t h o rs

3. Designing for people
Prof. Fionn Stevenson
University of Sheffield
Beyond Zero Carbon Housing 24th October 2012
The University of Nottingham

4. The UK intentions....
‘Zero carbon housing’ (regulated emissions only...) = 70% reduction on CO2?
PassivHaus standard = 15kWh for heating, lighting, ventilation (120KWh overall)
‘Smart housing’
‘Integrated design’
‘Changing behaviour’
Greenwatt Way
PRP architects
happy occupants....
(anybody home.....?)

5. The UK reality.... in new homes
overheating in homes, especially in urban areas..... unwanted heat gains
poor cross-ventilation
poor indoor air quality
malfunctioning, unintegrated new technology
unintelligible design (‘dumb housing’)
unusable products and buildings
unhappy occupants...

6. Current thinking in carbon reduction
Increasing emphasis on user behaviour
to explain the gap between Intention
and reality
Danger of ‘blaming the user’……not
design
More work needed on evaluating
the underlying usability of the design
and how needs are defined

7. How do humans work?
we are a product of millions of years of evolution....fine-tuned monitoring
we have primitive instincts and habits......hunter , gatherer, farmer
we operate through our senses and conceptual models
we are always meaning-making with whatever we have to hand
we are programmed for change, not continuity

8. How do humans work – mark 2
We want to conserve our own energy
We tend to go for the easiest option
‘Your nearest, so you do it...’
On-demand, all the time...
hidden charges.

9. Computer use UK homes - 2010
Coleman, 2011

10. Design issues with standby
Slow activation time
Physical location of sockets
Networking requirements
Poor controls
Lack of knowledge
Poor manuals

11. Affordance - design interfaces
Gibson’s ‘affordances’ = perceived and actual properties of things, which determine
how they can be used. The user knows what to do by sensing.
a chair ‘affords’ sitting
a window ‘affords’ opening
What you see is what you get
Do digital technologies
really do this for energy use?

12. Evaluating usability – the six criteria
Clarity of purpose
Intuitive design
Labelling
Ease of use
Feedback
Degree of fine control
‘Controls for end users’
Bordass, Leaman and Bunn

13. Key control touchpoints in the home
Heating programmer, VDU, switches, dials
Ventilation windows, doors, handles, hinges, trickle vents, ventilation units,
switches, dials, VDU, filters, ducts
Lighting switches, VDU, light bulbs, shading, control panels,
Water taps, plugs, showers, baths, dials, switches
Lets look at some in use....

14. Evaluating usability in BPE –woodstove
controls
Wood pellet boiler Description and location:
living room, main heat source,
Usability criteria Poor Excellent
Clarity of purpose
Intuitive switching
Labelling and annotation
Ease of use
Indication of system response
Degree of fine control
Comments
The wood pellet stove provides room heat and heated water to an accumulator tank in the roof
space. Additionally the solar thermal panels provide heat to the tank and there is also an immersion
heater. There is a panel in the airing cupboard which indicates the tank temperatures- top and
bottom- but although this accuately regsiters heat from the solar panels and the immersion heater it
does not relate to heat from the pellet boiler so it requires trial and error to control the whole
system.

15. Evaluating usability in BPE -woodstove

16. Evaluating usability in BPE –ventilation
control
diffusers Description and location:
diffusers in kitchen, bathrooms and ground floor WC ( GF WC one is not present in No 2)
Usability criteria Poor Excellent
Clarity of purpose
Intuitive switching
Labelling and annotation n/a
Ease of use
Indication of system response
Degree of fine control
Comments
Diffusers extract air only. No instructions were given for adjustment and the commissioning of system
was carried out by an OBU consultant. A fair degree of fine control can be achieved by spinning the
inner disc. The vent gives no indication of whether it is actually extracting air or not.

17. Evaluating usability in BPE -water
sink taps Description and location:
Usability criteria Poor Excellent
Clarity of purpose
Intuitive switching
Labelling and annotation
Ease of use
Indication of system response
Degree of fine control
Comments
There are no indications of movement for hot or cold water ot labelling. This is a highly non-intuitive
piece of equipment, although the movement is good.

18. Conceptual model of how things work
Our concept of how things work and their meaning is based on:
past experience
habit
instinct
sense
memory
logic
culture
physical context
feedback
We try to ‘make sense ‘ of controls with whatever faulty information we have.....
not always logical!

19. Conceptual congruency in design
designer user
design
model
user model
system
system
image
Norman, 86

20. Usable design –mapping
Mapping = relationship between two things e.g. controls and results in world
Natural mapping = immediate understanding from culture, biology, perception
Mapping problems = cognitive dissonance (‘does not compute, not logical
counterintuitive..’) – no direct spatial relationship

21. Things that go wrong with usability
too many features –too much information
smaller and faster is not always better
over automation
humans are irrational - users blame themselves
or wrong cause

22. Usable design – feedback
make feedback visible to tell user what is going on
provide accurate, embodied , feedback
provide more feedback, less features

23. Moving on from affordance to learning
affordance is ‘What you see is what you get’ (WYSIWYG) – physical
humans work conceptually also, and through time – we learn how to use things
products and buildings have emergent properties which create a relationship with the
user
maximum usability is when emergent properties reveal themselves easily
e.g. one thing leads to another – exploring a door handle....

24. Durable design increases usability
avoid perfection – make design scratchable
make design cherishable
increase the meaning through memory
avoid waste –embody habit over time
design for discovery not ‘cover up’

25. Co-evolutionary
design
positive emergence through
adaptive opportunities
with accurate feedback
design for users to interact
with building and learn with it

26. But how much can the user take?
Autonomous energy systems mean:
Individual maintenance
Individual replacement
Individual servicing
Transportation of small systems
to individual homes
Is this the most efficient way?

28. Access and maintenance of PVs
Does PV system tell occupant when it is not
working?
Is there an easy way to access and replace
panels?
Is the transformer sited somewhere where it
will not disturb occupants?
Is there room for all the kit??

29. Energy use – scale and efficiency
Many energy systems work best at neighbourhood/campus level = 10,000 people
Solar PV – best at regional level = 10 million people
Solar thermal – best at campus level = 10,000 people
District heating
District cooling – best at city level = 1 million people
Trigeneration
Heat pumps – best at building level
The only energy system which is more efficient at the level of a building is a micro-
grid system

30. Usability in design – the cinderella factor?
testing for usability only occurs in a
minority of key touch point products
lab tests are not user tests
architectural education does not teach
usability at the level of the user

31. Key challenges....
situating user values within design
understanding how humans work
in design
maintaining place-based approach
globalisation of resource use
architectural education….
include the user in design

32. Thank you …any questions?
Anybody know
how this thing
works ??
For more information please visit:
http://www.sheffield.ac.uk/architecture/people/stevenson_f