Staying Grounded with Green Roofs

Visiting a friend’s condo in downtown Vancouver the other day, I was impressed by the buildings ability to use its limited design space to incorporate private gardens for each tenant at the top floor of each unit. This building is not alone - As city infrastructure grows and green space is becoming more of a luxury, many developers are looking for creative ways to incorporate green space within their structures.

These areas of vegetation can take the form of green roofs, indoor green walls, or beautiful water features. Some add a mere aesthetic contribution, but others can actually add structural benefits to the building itself. Modern green roofs are an adaptation of Scandinavian sod roofs, built during the Viking and Middle ages. These roofs proved to be great thermal protectors, and reduced flooding and leakage by absorbing rainfall.

When an architect team (and couple) decided to design a home for their family in New Orleans, they designed a house to showcase green building practices. With a modern two-part design, incorporation of up-to-date building codes and a green roof, the home was originally intended as a “calling card” for their innovative architectural firm. One month after moving in however, Hurricane Katrina struck and the area of Bay St. Louis where they lived was essentially destroyed.

Upon returning to their home, they found the damage to be minimal considering the extent of the storm’s power, and their house sustained almost no structural damage. Their use of stronger materials, and compliance to modern building codes contributed greatly to the durability of their home in such a catastrophic event. Most notably, however, was the role that the green roof played in keeping the structure together, adding weight to help the home sustain the hurricane winds of up to 130 mph.

Not every home will face extreme weather conditions, but having a green roof adds other valuable benefits such as:

• Reduction in storm water runoff
• Enhanced thermal insulation
• Increased life span for the roof
• Improved air quality and reduction of the heat island effect in cities
• Green roofs can provide extra space to cities for recreation, activities or community gardens

Often when looking to future innovative building techniques, we find ourselves looking to the past to see what works and is proven to last. The future of green roofs is one such technique, with builder, designers and enthusiasts alike taking a more in-depth look at ancient traditions to build the infrastructure of the future.

Krystol Internal Membrane (KIM) is compatible with green roofs, by eliminating the need for a waterproofing membrane on the concrete slab of a green roof. KIM waterproofs the concrete by using the water to create crystals to block the concrete pores, and protects the structure from water damage for the life of the concrete.