Canadian Consulting Engineer

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Buildings: Enermodal’s Extreme Green

Stephen Carpenter, P. Eng., president of Enermodal Engineering, has been advising clients on sustainable building design for 15 years. His firm has grown by devoting itself entirely to green buildings...





Stephen Carpenter, P. Eng., president of Enermodal Engineering, has been advising clients on sustainable building design for 15 years. His firm has grown by devoting itself entirely to green buildings. In Ontario alone, Enermodal helped to design over 85% of the projects certified so far under LEED (Leadership in Energy and Environmental Design). One might say the firm has helped to write the book on green buildings, since it is currently coordinating revisions to the forthcoming LEED 2009 green building assessment system for the Canada Green Building Council.

Enermodal certainly follows its own advice in the design of its headquarters in Kitchener, Ontario and in its Calgary office. It also has offices in Toronto, Denver and Phoenix.

Currently, the company leases space in a building known as the “Green on the Grand,” in Kitchener, but due to lack of space, it is building a new headquarters at 582 Lancaster Street West.

Green on the Grand set the standard for green buildings back in 1995 when Carpenter helped to facilitate the design for the owner. Even now, “and almost embarrassingly,” Carpenter explains, Green on the Grand is believed to be the most energy efficient office building in Canada. Its energy consumption (gas and electricity) is closely monitored and currently runs around 120 kilowatt-hours per square metre.

For its new headquarters Enermodal has set “the audacious goal” of cutting the energy use to half that of the Green on the Grand. The new building is designed to use around 70 kW-hours per square metre.

An Audacious Goal for Kitchener

How is this audacious goal going to be met? Carpenter explains a few of their strategies.

First the building form: “It is a long, narrow, skinny building in the east-west direction. The building is only 40 feet wide, so basically every worker has a window and there is good daylighting.” Obviously this cuts down on lighting energy, but Carpenter says it also provides a more productive environment.

“The only challenge in our climate is to make sure you can meet the heating loads,” says Carpenter, “so we’ve gone with a fairly well insulated shell.” The structure is insulated concrete forms, “basically a sandwich of insulation on the outside of poured concrete.” As in the Green on the Grand they’re using triple-glazed windows with fibre glass frames.

Heating and cooling is by a variant refrigerant flow (VRF) system. These systems have units linked by piping, with the refrigerant flow adjusting to need. Carpenter explains that the system allows the individual units to run at half-speed, which gives greater energy efficiencies. It also gives much more precise control over conditions in each occupant area. “You have in essence got an air conditioning and heating system for every office,” says Carpenter.

Instead of using a central building automation system, they will rely on individual occupancy sensors and controls. The same sensors control the ventilation. “If there is a theme to the design, it’s Keep it Simple, Carpenter says.

In fact, these will be “vacancy” sensors rather than “occupancy” sensors. They will automatically keep the lights off until someone enters the room and physically switches them on. The sensors also trigger automatic blinds on the windows.

Another feature will be photovoltaic panels in the central atrium to generate electricity.

The building will have low-flow plumbing fixtures, and will harvest rainwater from the roof for non-potable uses. Together, Enermodal hopes these features will earn the building a LEED-Platinum certification.

Calgary Showplace

Enermodal’s 1,000-sq. ft. leased space in Calgary was the first to achieve LEED-Platinum Commercial Interiors (CI) certification from the Canada Green Building Council, which happened in October 2007. The CI certification is specifically for tenant properties, where the tenant and its designers have no control over the building’s infrastructure, but can apply green design to the fixtures and fittings.

Matt Grace, P. Eng., who heads the Calgary office, explains that Enermodal has been a tenant in the 11-storey Mission Professional Building at 23rd Avenue and 4th Street SW for two years. They recently took over a 650-sq. ft. adjoining suite.

Enermodal has made the Calgary suite into a showplace for clients who are seeking guidance on sustainable design. For example, they have installed a “green building kiosk,” which displays on an interactive screen how electricity is being used in the space, the carbon dioxide levels, etc.

There is also an 8 ft. x 3 ft. “living wall,” which uses greenery to cleanse the indoor air. As tenants, Enermodal controls the electricity use and changed the lighting to energy-efficient uplight fluorescent T5s onto reflective ceiling tiles, and compact fluorescents. The workspaces all have individual light sensors.

On the walls and floors, visiting clients can see recycled and green materials such as bamboo flooring which is free of urea-formaldehyde. There are low VOC carpets, and a rustic wall covering made using the waste from cutting marble. One of the walls in the boardroom is cut away, showing different types of insulation.

Grace doesn’t mind admitting some mistakes. They tried a “milk paint” on the walls, for example, but it began to peel off and had to be replaced. “The reason we try these things is so that we can have a broader base of knowledge on green products and can advise our clients better,” he says. –BP

Enermodal design team: Stephen Carpenter, Brian Pescod, Richard Lay, Tim Dietrich (new Kitchener headquarters); Matt Grace (Calgary office). Architect of Kitchener HQ: Robertson Simmons.