The Carbon Dioxide from construction
See Also: Carbon Footprint of Concrete
p75. “The building of an average house in York is responsible for the release of 68 tonnes of GHG emissions per capita. Over the life span of the building this figure becomes less because if the house stands for a hundred years, the CO2 output for each year becomes only 0.68 tonnes per capita.”
They also use as a source:
“Managing the Flow of Construction Minerals in the North West Region of England: A Mass Balance Approach”
Darryn McEvoy, Joe Ravetz, John Handley Journal of Industrial Ecology, Summer 2004, Vol. 8, No. 3, Pages 121-140
(doi: 10.1162/1088198042442289) which is available to subscribers
The average material content of a house
The building of an average house in York is responsible for the release of 68 tonnes of GHG
emissions per capita. Over the life span of the building this figure becomes less because if the house
stands for a hundred years, the CO2 output for each year becomes only 0.68 tonnes per capita.
“Estimates by Ray Cole of the University of British Columbia’s School of Architecture also compare embodied energy with operating energy. Cole’s figures relate to a 3,750 ft2 ranch-style home, constructed in either conventional or energy-efficient style.1 The energy-efficient version of this house includes R-42 ceilings, 226 walls, additional glazing on the south elevation, and added thermal mass. As in the other Canadian study, Cole’s figures reveal an embodied energy for both versions of the house that is equal to several years’ worth of heating energy, which is the major component of home operating energy in Canada (see Table 1). According to Cole’s data, it follows that the more operating-energy efficient the house is, the larger percentage embodied energy will be of the structure’s total energy.
“Another study, conducted by Andrew Buchanan and Brian Honey of the University of Canterbury
in New Zealand (which has a similar range of climates to California) concluded that the energy
required to manufacture a house is of a similar order of magnitude to the energy required to heat
the house over a 25-year life (see Table 2). That study drew upon research conducted at New
Zealand’s Energy Research and Development Committee in 1983, which among other things
estimated “energy coefficients” for various building materials (see Table 3).”
Table 7.4 Altered carbon dioxide values, to include non-energy related sources (all values are in kg of carbon dioxide produced).
For similar house to Buchanan and Honey (say 375 m2 = 3,750 ft2 see above) Joanna Glover gives
Further mention needs to be made of the carbon dioxide values obtained for concrete, both
within each house and overall. While the majority of carbon dioxide emissions from both the
steel and wood components are incorporated in the burning of fossil fuels to generate energy,
the manufacturing stage of a concrete LCA generates a significant quantity of carbon dioxide.
This occurs in the calcinating of limestone, producing calcium oxide and carbon dioxide, during
cement production (which usually comprises 12% of concrete, as mentioned previously in
Chapter 2). In the production of Portland cement (accounting for the production of 95% of
North America’s cement), around 0.75 tonnes of CO2 are produced per tonne of cement from
fossil fuel combustion in the rotary kiln, and a further 0.5 tonnes of CO2 per tonne of cement
is released through the reaction of limestone . Converting these to values per unit concrete
production, gives an extra 0.06 tonnes of CO2 produced per tonne of concrete from the
calcinating of limestone. With this addition, and the assumption that all other carbon dioxide
releases into the environment from the steel and wood process are considered negligible, the
values calculated above should be appropriately adjusted. Table 7.4 displays the newly manipulated data.
See the setion at the end “Our Cities: Green Building for Sustainability”:
“Concrete is the most commonly used construction material in the world and is the second most
consumed product in the world after fresh water. Concrete is made with 10-15% Portland cement,
which requires heat and energy inputs resulting in about one tonne of greenhouse gas emissions
for every one tonne of cement produced.”
“Enter the EcoSmart Foundation, which researches and advocates the use of supplementary
materials for Portland cement. By using fly-ash or other industrial by-products, environmentally
friendly concrete can be produced that is generally cheaper and stronger than traditional concrete.
Awareness and supply are the key challenges, and the use of EcoSmart concrete is one way that
building materials can become more ‘green’. ”
Discussion here, disputing the 68 tonnes CO2 above, gives:
“Order of magnitude: If a new 100 m2 semi-detached house takes
100,000 kWh of primary energy to construct as stated by Chapman
in 1976 and the CO2 emissions of this primary energy are 0.25
kg/kWh (typical of oil), that’s 25,000 kg = 25 tonnes CO2.”
I have found what seems to be an authoritative source concerning BEDZED (the Beddington Zero Energy Development):
“Construction Materials Report for the Beddington Zero (Fossil) Energy Development” by BioRegional (http://www.bioregional.com)
This gives the embodied energy of the development as 650 Kgs CO2 per square meter. That is 65 tonnes CO2 for a 100 m2 flat.
I think the BRE Group is the source for the figures – they are a privatised ex government laboratory. See the discussion on the AECB board:
Should we use 65 tn CO2e for an average house?
I understand the Government is planning 240,000 new homes a year. If each creates a similar amount of CO2 during their construction as BEDZED, they would produce more than 15 million tonnes of CO2 per year. That is more than a quarter of a tonne per person in the UK. Related and other aspects of construction (roads, schools etc) will increase this figure.
Using wood products to mitigate climate change
International Institute for Environment and Development
Using wood products to mitigate climate change:
How does this analysis compare with BRE (Building Research Establishment) methodology?
Ecological Footprint of York
“A Material Flow Analysis and Ecological Footprint of York” from the Stockholm Environment Institute, York University :
“The study has attempted to understand the total material requirement of the City of York and then establish the ecological footprint associated with the consumption of these materials.”
Construction Materials Report for BedZed
Construction Materials Report for the Beddington Zero (Fossil) Energy Development.
“The report describes all the materials used in the construction of BedZED. It shows how we reduced the embodied environmental impact of the development by some 20-30% by selecting reclaimed, recycled, local and low impact materials. It provides a “Toolkit” of how to achieve this environmental saving on any construction job without incurring additional cost!
“The report includes embodied energy analyses, life cycle analyses and environmental profiling comparisons by the BRE. It provides case studies for individual materials and cost comparisons with alternatives. It describes in detail how the materials were sourced, specified and used, with contact details of suppliers and contractors.
“Written by Nicole Lazarus, the ZED Project Manager at BioRegional Development Group, the report is funded by Biffaward and the DTI’s Partners In Innovation programme. It forms Part 1 of the Toolkit for Carbon Neutral Developments. ”