Environmental impact of buildings amd sustainable architecture

1. Lect. 2
Adama (ASTU) March 16, 2022
Environmental impact of buildings

2. Content
 construction material production
 Construction and demolition
 Building operation
 Pillars of sustainability

3. How do buildings affect the environment?

4. Buildings have a big impact on the environment
• Building environmental impacts can be analyzed from multiple perspectives,
1. Type of building
2. life cycle phases and
3. Type of environmental impacts

5. The environmental impact of construction material production

6. OBTAINING AND PROCESSING MATERIALS
Obtaining and processing materials can affect the environment in three
main ways :
1) EXTRACTION
2) PROCESSING
3) TRANSPORTATION

7. EXTRACTION
• This requires heavy plant which consumes energy and produces noise, dust
and exhaust fumes, which leads to climate change
• This process also causes a permanent change to the landscape e.g.
stone/aggregate quarrying
AGGREGATE QUARRYING

8. PROCESSING
• Processing the material e.g.
iron ore requires energy
consuming plant
• produce noise, dust and
waste products e.g. slag
AIR POLLUTION LEADS TO THE GREENHOUSE EFFECT AND CLIMATE CHANGE
BLAST FURNACE

9. TRANSPORTATION
Once processed, the
materials will then need
to be transported to the
location which they are
to be used, using petrol
and creating exhaust
fumes, which in turn
causes climate change

10. Materials used in construction environmental impacts.
There are 4 main materials used in construction
1. Timber
2. Metal
3. Concrete
4. Plastic

11. • Deforestation: more than 25% of the world’s tropical forests have been cleared
since 1960.
Loss of animal and plant species
TIMBER

12. METALS
METAL ORE QUARRYING

13. CONCRETE
• Made from limestone, chalk, clay,
aggregate and gypsum
• These raw materials must be mined then
processed, which requires a huge
amount of energy
• It is estimated that 8% of the total
worldwide human generated CO2
originates from cement production

14. PLASTICS
• PVC products include windows, doors, soffit,
fascia, rainwater goods, electrical and plumbing
components
• Needs large amounts of energy to produce
• creates hazardous waste products e.g. dioxins

15. EMBODIED ENERGY: Is the energy required to produce and transport materials
MATERIAL ENERGY FOR PRODUCTION (MJ/kg)
TIMBER 1
BRICK 4
CEMENT 5
PLASTIC 6
GLASS 14
STEEL 24
ALUMINIUM 126
excluding transportation energy

16. Environmental impact of construction process
• Construction & Demolition generate between 10% and 40% of the solid
waste stream in most countries (Kibert et al, 2000).
This waste used for low-priority works like footpaths, drains, pavements
etc.
Most bonding & drying agents in carpets, veneers, particle board, plywood
and paint emit volatile organic compounds (VOC’s) which contribute to
greenhouse gases and global warming.

17. Permanent change to landscape
Noise/dust pollution
River pollution
Ground pollution/landfill
Cont..

18. • Another way that buildings release greenhouse gases is simply the
way they are operated.
• Through the use of electricity and fossil fuels such as oil and gas,
buildings negatively impact the climate with their carbon emissions.
• We typically think of lights, ovens, and refrigerators causing the most
damage. However, heating and cooling units use the most energy!
Building operation

19. Global ABC, global status report 2018, EIA
THE BUILDING SECTOR
• Buildings account for around
35% of resources, 40% of
energy use, consume 12% of
the world’s drinkable water
and produce almost 40% of
global carbon emissions.

20. EXISTING BUILDINGS
IEA Energy Technology Perspective 2020, February 2021 revised edition

21. NEW CONSTRUCTION
Global ABC, global status report 2017
To accommodate the
largest wave of urban
growth in human
history, we expect to
add 2.4 trillion ft2 (230
billion m2) of new floor
area to the global
building stock, the
equivalent of adding an
entire New York City to
the world, every month,
for 40 years.

22. EMBODIED CARBON
UN Environment Status Report 2017; EIA International Energy outlook 2017

23. Achieving zero embodied emissions will require adopting the principles of:
 Reuse, including renovating existing buildings, using recycled materials,
and designing for deconstruction.
 Reduce, including material optimization and the specification of low to
zero carbon materials.
 Sequester, including the design of carbon sequestering sites and the use
of carbon sequestering materials.
EMBODIED CARBON

24. Pillars of sustainability
The concept of three pillars of sustainability originated in the 1980s under different
schools of thought, later institutionalized by the UN.

25. Social sustainability of buildings
• Management and integrated process
• Participation
• Function and usability:
’effectiveness, efficiency and satisfaction’
• Functional mix
• Flexibility
• Comfort and well being
• Education
• Aesthetic
• Using exterior space
• Safety
• Inclusivity and accessibility
• Equity and affordability

26. Environmental sustainability of buildings
• Site selection
• Pollution and Carbon emission
• Energy
• Material and waste
• Water
• Transport
• Healthy indoor environmental quality
• Biodiversity and greenery
• Adaptability

27. Economic sustainability of buildings
• Life cycle coast
• Net present value
• Return on investment, Return on capital employed
• Internal rate return
• Management and monitoring
• Commercial viability

28. Pillars of sustainability
Environmental impacts
 Resource depletion
 Physical disruption
 Chemical pollution
 visual pollution
Social impacts
 Loss of open space & biodiversity
 Social Isolation
 Increased car dependency
 Decreased air quality
 Unhealthy indoor environment
Economic impacts
 To Builders:
 Increased compliance costs &
waste disposal costs
 To Owners:
 Increased utility &
maintenance costs
 To Occupiers:
 Loss of well being &
productivity
 To Society:
 Decreased environmental
quality