Life Cycle Assessment & Energy Efficiency

LIFE CYCLE ASSESSMENT AND ENERGY EFFICIENCY

Impartial and unbiased scientific research demonstrates that when Timber is environmentally evaluated across its entire life span from extraction to processing and through to total life usage and final disposal, it can compare favourably with any alternative material.
As trees grow they naturally absorb CO2 from the atmosphere. A typical tree absorbs 0.9 tonnes of carbon for every cubic metre of growth.  Trees are essential in the fight against climate change.
A cubic metre of wood contains roughly 0.8 tonnes of CO2
The production of sawn goods consumes considerably less energy than for other building materials.  Concrete requires double the amount of energy whereas Brick production requires Four Fold the amount.  Even though further wood processing, such as Chipboard manufacture, requires many more times the energy than is used for sawn timber most of this is renewable wood energy generated at the mill.  On top of this Aluminium is the most energy intensive of all materials.  Source: Puu info 2008.
When comparing like for like construction.  The building of a similar sized warehouse with wooden walls consumes 1500GJ of energy compared with the same building in steel walled elements consuming 3000GJ.  Source: The Year of Wood/TRADA.
Achieving low-energy housing is more cost-effective using timber-frame construction than conventional brick and block. Well constructed timber framed dwellings can comfortably deliver significantly better levels of air permeability than the required limit under building regulation requirements, by using 140mm stud solutions and full depth insulation, can achieve 0.27W/mK
When comparing like for like items such as windows:  To produce a standard size wooden sash window requires 64kwh of primary energy whereas aluminium requires more than ten times this figure.  Source: Katalyse GmBH.
Wood windows which are double glazed and painted in the factory have 30 year durability warranties, paint guarantees of up to 10 years and can provide improved energy ratings, beyond Part L requirements depending on the type of glass selected.  Wood windows are easier to triple glaze too.
The LCA-House model for comparing the construction of exterior walls conducted by The Technical Research Centre in Finland concludes: The largest amount of renewable energy and least amount of fossil fuel energy used in wall construction is one built from wood and it causes the least amount of greenhouse gases and sulphurous emissions.  Walls produced from concrete consumed the largest amounts of non renewable resources and produced the largest emission amounts of Carbon Dioxide per square metre of wall.  Source: LCA-House model Sirje Vares VT Building & Transport.
The Canadian Institute of Sustainable materials, Athena, has used the Life Cycle Assessment (LCA) method to evaluate buildings with a frame of wood, steel and concrete.  When compared with a range of environmental criteria, the wood frame building was the clear winner.  N.B. The research was based on conditions in North America and the size of houses and levels of energy consumption were the same for all buildings, only the frame and wall materials differed.