News
Breath of fresh air with N.S. living wall

Oct. 9, 2009, Halifax — From a
distance, it looks like a really ambitious mural. But up close, the newly
installed living wall at Saint Mary’s University is, well, alive.

Oct. 9, 2009, Halifax — From a
distance, it looks like a really ambitious mural. But up close, the newly
installed living wall at Saint Mary’s University is, well, alive.

Three storeys of plants, more than a
thousand of them, are in Atlantic Canada’s first living wall, part of SMU’s new
$17.5-million Atrium, a connector building that links the university’s library
to several other academic buildings. Work on the Atrium started a year and a
half ago, and the construction crew putting on the finishing touches does its
work in front of a steady stream of students.

“If you go up close enough, you can
actually hear the water going down and you can see the water droplets,’’ said
Caitlin Dix, the student rep on SMU’s sustainability committee. “There’s water
running the whole time, it goes all the way down and then back up through a
system, and back down again. They’re constantly being watered at their roots.’’

The 14 species of plants, all from
Florida because there aren’t any native plants that stay in leaf all year
round, were installed over a week in September. The project is scheduled to be
completed within the next couple of weeks and the wall, while esthetically
pleasing, is more importantly something of an air improvement marvel.

“About 19,000 cubic feet of air per
minute is going through that wall, back down to our general ventilation system,
then it’s shot back up into the area, so it just keeps circulating around,’’
said Gary Schmeisser, director of facilities management for Saint Mary’s. “We
pull air through the plants into ducts, then heat or cool it, mix a little bit
of outdoor fresh air in, then put it back into the area.’’

The process increases the rate at
which carbon dioxide, breathed out by humans, is converted to oxygen. So, no
longer can stuffy air be used as an excuse for getting drowsy in the library.

“We have to bring in less air from
the outside, so during the winter we heat less air and during the summer we
cool less, so our energy costs should go down. It’s a new thing, so we haven’t
found out how much yet,’’ Schmeisser said.

He promised the difference in air
quality will be noticeable.

Dix, a graduate student with a BA in
environmental studies, said the university had students on the committee struck
to oversee design of the Atrium, appropriate given the interest in the
environment by young people.

“Our generation has grown up with
‘be sustainable, recycle.’ It’s really instilled into our brains now. So we see
a living wall, we think ‘Oh, a living wall. Yeah, it should be there.’ And for
students studying it, they can see and touch the actual application,’’ she
said.

“The students have been pushing for
sustainability, for the big things on campus to be more sustainable, with the
green roof that’s also happening. I’m not sure that every student understands
exactly what a bio-wall is yet, but they understand that it’s something that’s
helping us towards our sustainability goals.’’

Saint Mary’s has been looking at
ways to be kinder to the earth since at least 1971, when a grass roof was
planted on the newly completed library. One benefit of a grass roof is that it
retains rainwater so there isn’t as much runoff into storm sewers.

But decades of mowing that roof led
to hope of a better way, and now a SMU biologist is developing plants to be
installed next spring on the roof of the Atrium. The new roof, divided into 16
sections, will be open to visitors.

“You don’t want to worry about
weeding, about mowing,’’ Schmeisser said. “It doesn’t dry up in the summer, or
die in the winter.’’