Recently I’ve become a bit fascinated with the green roof concept. I at least found them visually appealing, and certainly on the surface they looked like a great concept.
This prompted me to do a little bit more research into them. And it turns out there are a lot of problems with them that you might want to be aware of.
A Poorly Designed Green Roof Can Cause Damage
If you’re going to take the plunge and get a green roof then you will need to hire a professional green roof engineer. Some people have just gotten up there with plants, water, and soil and have tried to do it themselves.
These people pay the price. Your roof isn’t necessarily designed to bear the heavy load of a living roof. You could get a roof collapse if you try to DIY this project.
If you don’t get a collapse you could still get leaks, as well as water damage to other areas of your home.
Unless your new “green roof” is 100% organic you’ll probably be spraying it with pesticides and herbicides. The runoff of those products isn’t any more environmentally friendly than normal roof run-off is.
They Attract Wildlife
You’re basically putting an animal’s habitat on your roof. Some of them are bound to get inside, and that means you could be facing a serious pest problem. In Florida, that’s a real issue.
Your Roof May Have Too Much Pitch
A green roof does best when there is little or no pitch. Most houses have a roof with too much pitch to accommodate this type of roof.
No, They Will Not Replace Your Gutters
A lot of green roof contractors try to sell this type of roof on the idea that you won’t have to worry about gutters anymore.
In a place like Arizona, that might be true. However, in the Tampa Bay area those plants are never going to absorb so much rain water that you won’t need gutters to divert and deflect some of it as normal. If you’re considering this in the hopes of avoiding the bi-annual gutter cleaning then you might want to reconsider.
There are Better Options
“White” roofs help to reduce urban heat spots without all of the risks. Environmentalists have also forwarded the concept of a “blue” roof.
A blue roof reduces stormwater runoff by focusing on rainwater collection. This is not so much a change in your roof type as it is a commitment to rainwater catchment, which we’ve been talking about on this blog on a regular basis.
I’m all for sustainability, but not at the expense of safe, livable housing. I think there are better places for your garden than your roof, and I think that there are better cool roof designs.
But I have to admit, I’m disappointed. Green roofs are really, really pretty.