A Roofing Membrane that Actually Cleans the Air
Posted by david.luukas
Trevor Lang, Technical Manager – Roofing Division for Alumasc Exterior Building Products, explains how bituminous roofing membranes can help in the battle against global warming.
Putting ecological roofing membranes on the market is good. Designing membranes that actively purify the air and contribute positively towards reducing global warming, by battling against the most prevalent of greenhouse gases, is even better!
Helping protect the environment
Historically the positive associations between bitumen and the environment have been limited. However, Alumasc’s Derbigum Olivine changed this and shows that bitumen can indeed play a meaningful role in the battle against rising CO2 levels in the atmosphere.
Because the amount of CO2 in the atmosphere is hundreds of times higher than the amount of other significant hazardous compounds, such as N20 (Nitrous Oxide), Alumasc chose to tackle this kind of pollution actively. And, after much detailed research and experimentation, they developed the Alumasc Derbigum Olivine roofing membrane.
Whilst other so-called ‘environmentally friendly’ membranes incorporate titanium dioxide, which requires the use of either sulphuric acid or chlorine gas in its production, the Olivine in Alumasc’s Derbigum Olivine surfacing is a 100% naturally occurring and environmentally safe mineral (magnesium iron silicate) which simply requires grinding down to the right size for it to be used in this application.
So how does it work?
The purification of the air takes place when it rains, when the CO2 is literally washed out of the air.
When the rainwater comes into contact with the olivine, an irreversible chemical reaction takes place which transforms the CO2 into three environmentally-harmless substances – water, magnesium carbonate and sand.
Research conducted by Prof. Dr. Olaf Schuiling at the University of Utrecht showed that 1kg of Olivine neutralises 1.25kg of CO2, which means that for every square metre of Alumasc Derbigum Olivine roofing membrane 1.75kg of CO2 is neutralised (there are 1.4kg of olivine granules per m2 of Alumasc Derbigum Olivine roofing membrane).
A very durable solution
From an ecological perspective, Alumasc’s Derbigum Olivine is a very durable solution and is the only bituminous membrane to have been given a 40-year BBA (British Board of Agrément) durability statement.
Olivine is completely UV resistant, meaning that its effectiveness is not degraded when in situ by the sun’s rays, and even with natural ageing, the active compound of the olivine will still be present when the roofing membrane itself is at the end of its lifespan.
Alumasc’s Derbigum Olivine is an Atactic Polypropylene (APP)-modified product which is suitable for use in all temperature zones and has already been utilised on a number of prestigious projects in the UK, including the Shard.
For further information regarding our Derbigum Olivine Flat Roof Membrane or to request a free sample and brochure click here.