Live Roof® is a unique green roof concept designed through the eyes of a horticulturist, founder Dave MacKenzie. The Company utilizes a patent pending, hybrid modular system with a optimal plant mix and soil composition. Since every region is different, Live Roof® has partnered with a network of horitculturalists around the US and Canada who are committed to finding the best green roof plants for their local conditions. Watch the video interview below as Dave MacKenzie described the benefits of Live Roof® system.
The Benefits Behind a Green Roof
- Reduce your air conditioning cost (30-50% reduction)
- Shelters the roof from sun, high temperatures, and the wind. According to MacKenzie, roofs are replaced every 20 years. With a green roof, the roof life is extended an additional 20-30 years.
- Avoidance of storm water municipal charges
- In addition, there may be credits or rebates for installation of a green roof
- Restoring habitat
- Social benefits: being surrounded by greenery you tend to be more creative and productive.
- Healing benefits as exhibited by patients in hospitals surrounded by a green roof
- Reduction of Urban heat island effect
- Noise reduction
- Fire Prevention
See here for potential LEED credits in connection with the installation of a green roof.
What makes Live Roof Different:
The Company states:
“Each LiveRoof® module arrives to the job site with full- grown plants inside the container and is simply set in place on the rooftop. The unique patent-pending Soil Elevators ™ are then removed for a seamless fit. No need to start with a brown roof and farm it for years, waiting for it to become a green roof.”
As MacKenzie explained to me, the soil on a green roof is quite different than what is in your container pots or gardens. Live Roof’s modules contain the lightest weight soil that will hold its composition essentially forever. In addition, the soil will provide enough moisture and mineral holding capacity that will support the plants in a healthy manner for an indefinite period of time. MacKenzie has found that certain green roofs fail because they have too much organic material and therefore hold too much water causing plant failure.
He indicated that competitors’ roofing systems are made out of mineral components that are too soft, so over time the particles break down, and causes a reduction of water through the system. He concluded that most green roofs tend to be constructed not from a horticulturalist perspectives but more from the concept that a roof top will be dry and provide too much water for drought tolerant plants which become diseased and ultimately fail.
(Note, in the video, MacKenzie provided me with a botany lesson about soil composition. I urge you to listen. You will never look at soil the same way.)
MacKenzie further explained planting material choices is paramount to keep the cycle of replacing organic materials rather than fertilizer. In a Live Roof® system, certain plants shed their leaves, which adds organic materials back into the soil.
What Type of Plant Mix is Used?
“CAM plants are unique in that under drought conditions their stomates (leaf pores) are open at night rather than during the day (as is the case with most plants). CAM plants exchange gasses (oxygen and carbon dioxide) in the dark when it is cooler and less windy and therefore conserve water. And, CAM plants are up to ten times more efficient with water conservation than non-CAM plants.”
The plants chosen are based on region, which may include Sedums, Alliums, Sempervivums, Euphorbias, Delospermas, and other species. In addition, Live Roof only uses cuttings not plugs and found the cuttings create less long term maintenance. The plant mix includes evergreen, semi-evergreen, and deciduous species to make a carpet like affect on the roof and continuous color throughout the year.
Live Roof Maintenance
With all this beauty, comes maintenance. I asked MacKenzie what the cost of maintenance was for the roofs. Usually, it is 5 to 10 cents a square foot. The higher number will be due to harder roof access, smaller roofs, and travel time. In addition, if the roof is not maintained the costs will increase. He recommended bi-monthly maintenance program to remove weeds before they become a problem.
Unique Live Roof Modules
According to MacKensie, the secret as to why a Live Roof® looks like a meadow is their 100% recycled plastic modules use Soil Elevator™ and Moisture Portal™ technology to unite the plants into one soil continuum. (All modules are made in the US.)
“LiveRoof® ‘soil elevation’ design and Moisture Portals™ unite soil across the entire green roof strata for sharing, not compartmentalization, of water, nutrients and beneficial organisms. This allows for the plants to be healthier, and hot, dry and wet spots are avoided.”
So, what is the payback for this type of system? MacKenzie explained in area where there is hot climate, the payback might be quicker due to decrease in cost of air conditioning. However, in a colder climate, the payback may be longer. As he further explained, the payback could be 20-30 years and therefore, the decision to install a green roof is not always a cost/payback analysis. Other factors will be taken in account as noted above. However, I noted that if there were incentives such as for renewable energy, the cost could be more palatable.
Depending on the size of the roof, labor, and access to the roof, the cost can vary from $12 a square foot to a complex labor intensive installation of $30 a square foot. MacKensie views that a Live Roof® system has more value over it life than simply the acquisition cost payback. In essence, green never felt or looked as good. For more common questions about Live Roof®’ system, see the FAQs on the website. In addition, see the showcase of installed green roofs.
Join the Conversation:
- What are your thoughts about installing a green roof?
- Has your company installed a green roof? If so, what were the benefits?
- How do you feel about the cost versus the environment attribute of a green roof?
- Thoughts about Live Roof®’s concept as to plant mix, modules, and other component?
Photos courtesy of Live Roof®.