Arab Construction World – October 2008
Building “green’ is increasingly becoming a necessary part of a construction firm’s best practices. Instead of just being a niche sector, green building is now at the forefront of design and construction.
The rigorous LEED (Leadership in Energy and Environmental Design) Green Building Rating System is rapidly becoming the standard for measuring a building’s environmental performance. Only introduced in the US in 2000 and in Canada in 2004, LEED standards are encouraging the construction industry to create buildings that are environmentally responsible, healthy, and profitable. Governments at all levels across the US and Canada are imposing regulatory requirements to ensure new public buildings meet a certain LEED standard.
With growing global pressure to go green, more eco-friendly products are being developed. “Green concrete” used to refer solely to concrete that had set but not hardened. Today, it also means concrete that’s made with recycled alternative materials such as reclaimed fly ash: a by-product of coal burned at power plants. Usually trucked off to landfills, the tiny glass particles of fly ash are now being used in place of traditional Portland cement to make concrete. Not only does adding fly ash increase concrete’s strength and durability, but this substitution reduces the greenhouse gas footprint of concrete.
Another green innovation is a new concrete recipe spiked with titanium dioxide: a compound often used in sunscreen products. This new cement becomes chemically active in sunlight and neutralizes air pollutants such as benzene, carbon monoxide, nitrogen oxide, and others.
Finally, there is pervious concrete. Originally used a century ago in Europe as structural insulation, pervious concrete is a permeable, porous material. This environmentally friendly material is now making a resurgence in places such as parking lots, because it allows storm and nuisance water to filtrate into the ground, recharging ground water, and resulting in zero discharge of polluted runoff into waterways. This in turn reduces urban flooding, improves the health of adjacent trees, and reduces or eliminates the need for storm drain infrastructure.
However, more often in buildings and construction, it’s waterproof concrete that’s needed. Increasingly, in the new LEED-based paradigm, the old methods of waterproofing concrete with oil-based membrane sheets are just not environmentally acceptable.
Environmentally responsible waterproof concrete
While concrete on its own has huge advantages as a green building material, making it waterproof using old-fashioned, externally applied membranes is less acceptable in today’s eco-conscious environment.
External membranes are often petroleum based and are typically applied using adhesives with highly volatile organic compounds. The high vapor pressure from these compounds can cause respiratory problems and are a contributor to “sick building syndrome.” Oil from conventional membranes can also leach out and contaminate drinking water.
One company offers products that are a significant solution to today’s “green building” pressures. Kryton’s integral crystalline technology permanently seals concrete by plugging its natural pores and capillaries and blocking the movement of water. It reacts with incoming water to self-seal the cracks that inevitably develop in concrete, protecting structures against water and contaminants that can weaken or destroy concrete and corrode steel reinforcements. Kryton’s integral crystalline technology, Krystol®, creates strong, waterproof, environmentally-safe concrete.
Although only buildings, not materials, can be certified as meeting LEED standards, Kryton products can contribute to achieving valuable LEED points in a variety of ways:
It’s predicted half of North America’s existing infrastructure will need replacing in the next 20 years. Kryton is making sure sustainability plays a big part in rebuilding North America.
Strong, waterproof concrete (waterproof from the inside out) is key to tomorrow’s environmental sustainability