Houseplants and fresh air

I'm not sure about whether such a study would be accepted by USGBC for an ID credit, but I really hope so! Better studies are sorely needed in this area.

Most of the articles and books that tout the benefits of indoor plants depend on a NASA study that dates to the 1980s. This study found that plants removed toxins, but later studies showed that to have an effect in a large space, you'd need about two and a half plants per square meter! That's a LOT of plants, and a lot of soil, and a lot of moisture, and a lot of potential bugs and diseases.

Other studies have focused on health and productivity gains related to indoor plants, finding that people tend to stay more focused, work faster on tasks, and use fewer sick days when there are plants around. There's a lot more work to be done in these areas, however. For example, it's still unclear if real plants have an advantage over artificial ones or paintings and photos of natural scenes.

I've spoken to quite a few people about the use of plants in buildings, and the one thing I keep hearing is that you have to account for the moisture load of the plants early in the design process. Otherwise, if you load a space with plants (that need water), you might run into moisture and air quality problems. You also need to pay attention to what's being used on the plants—it doesn't make sense to bring a lot of pesticides into an office that's been designed to maximize indoor air quality! There are organic plant care companies out there, and they're worth seeking out.

I wrote a longer article on plants in buildings last year, that's available here. (Link requires paid membership to BuildingGreen.com.)

If you figure this out, please comment back here--I'd love to hear what USGBC has to say!

Wagner, if this has been attempted, I have not heard about it and it hasn't been publicized by USGBC in their ID point catalog (see the Resources tab, above).

As a general rule, you would need to apply the credit's criteria of:

- representing an innovative approach
- comprehensive in scope
- quantifiable environmental benefit.

For reasons outlined by Allyson, I think you would have to go pretty far toward arguing for the benefits, particularly in terms of the quantifiable benefit.

If anyone's gone further with this, I would love to hear about it.

Our office CI was granted a point for this in the Innovation in Design category. We had someone on staff who was a Horticultural Consultant. She developed the plan and performed extensive research on plant types and sizes to specify that would reduce the concentrations of formaldehyde, etc in the office area. It is possible but takes a lot of work!