Avoiding Mold vs. Saving Energy

Nice job on the mold article (

EBN

Vol. 10, No. 6 – June 2001). I do have a question on the checklist for minimizing mold risk that perhaps has more to do with the difficulties in using checklists as well as life-cycle assessment (LCA) approaches. Under the building operation section, one of the points is “avoid surrounding buildings with vegetation,” a point whose explanation includes concerns about the ability of vegetation to shade and limit air circulation. From an energy conservation point of view, these abilities can be employed advantageously, though from the IAQ perspective (the point of the mold article) there are some concerns. So how does someone weigh these conflicting benefits and costs? As you know, this is a challenge in LCA work. I’m just a bit concerned that folks, scared by images and stories of mold problems, won’t remember the good things that vegetation around buildings is responsible for and end up unnecessarily using more energy for space conditioning. It’s a tradeoff, but one that requires balance and information to make. You all at

EBN do an excellent job of providing information and balance, and I was a little surprised that only one side of the vegetation around buildings tradeoff was presented.

Geoff Lewis, PhD pre-candidate

Taubman College of Architecture and Urban Planning

University of Michigan

Editor’s Response:

This is an excellent question—and it points out the challenges of trying to compress a lot of information into a relatively short article format! You are correct, vegetation around a building can provide very significant benefits, having to do primarily with energy savings. Fortunately, in a very humid, rainy, or cloudy climate—where the risk of mold (and algae) growth is the greatest—the energy benefits of shading will generally be lower than in a hot sunny climate. One can still generally benefit from vegetative shading to a maximum extent where it is most needed (in a hot, sunny climate) without significant risk of mold problems (though insect entry may still be a concern). In a mixed climate, I would recommend a compromise—using vegetative shading to a lesser extent and keeping at least several feet of distance between the plants and the building. – Alex Wilson