As Quantity Surveyors, we deal with numbers every day related to the cost of Construction of Buildings and infrastructure and we learn to tell the story and understand what the numbers are actually telling us about construction cost.
We cannot continue to put our heads in the sand and ignore what the demands on construction material are doing to the future of the planet and that excessive use of limited resources is not sustainable.
What I have learned in my journey is that use of engineered timber such as CLT (Cross-laminated timber), glulam and LVL (Laminated Veneer Lumber) confronts climate change by being a store of carbon.
Simple mathematics! Every 1 m3 of timber=removes 0.8 tonnes of CO2
C02 is absorbed by the timber and the carbon is stored/sequestrated and oxygen released- thus 1m3 CLT will have 240-250kg of locked in carbon.
So what? Well, studies by Engineers such as Smith & Wall work undertaken on 3/11/2016 (for further information contact Katherine Symons at BMC) have shown in a comparative study of 4 structural frame solutions considered for the same typical 6 level accommodation block.
Consider the following factual numbers:
Portland Cement results in around 870kg of CO2 emissions per tonne cement according to “the cement industry’s role in climate change, Dr. Robert McCaffrey, Global Cement & Lime magazine.
The cement industry is one of the primary producers of carbon dioxide, a potent greenhouse gas and is one of two largest producers of carbon dioxide creating up to 5% of worldwide man-made emissions of this gas.
The production of steel results in around 1.75 tonnes of CO2 emissions per tonne of steel (The Carbon Trust).
The world produces enough steel to build an Eiffel tower every 3 minutes and 24 seconds! Steel production is energy consuming and requires large inputs of coke ( a type of coal) that emit toxic air pollution.
This sounds serious and may be why we are acting like ostriches by putting our heads in the sand! What can we do? There are some positive steps we can take and no doubt solutions will comprise a balanced approach with the use of the appropriate material for what is required.
But what is certain is that the time has come for us to seriously consider the facts and address the challenges. That will be part of another discussion then!