We design our walls for long life, active filtration and ecological integrity.
Basic green walls often feature potted plants fed by a system of water trays, which means the plants are easy to source and replace. It also means that the roots of the plants are constrained, subject to too-dry or too-wet conditions and unable to clean air efficiently. When evaluating the functionality of green walls, remember this: it is the microbial action in the root network that cleans the air; the plants are simply sustaining the environment. Anything that constricts or isolates the root system of a living wall will also limit your opportunity to put nature to work.
How it works
BIOFILTRATION
Biofiltration is the passing of a contaminated air stream through a biologically active area where beneficial microbes use pollutants, such as VOCs, as a food source. A Nedlaw biofilter moves the air stream through on-boards fans or by connecting to an HVAC system.
PHYTOREMEDIATION
The second technology is phytoremediation. This is how plants facilitate the beneficial microbial activity: the products of photosynthesis – oxygen, sugars and proteins are shuttled to the roots where a substantial amount is ‘leaked’ to the soil. The increased nutrient availability leads to enhanced microbial activity.
HYDROPONICS
As you probably know, hydroponics is the process of growing plants in liquid nutrient solutions rather than soil. Our system pumps water from a basin at the bottom of the wall to the top; the trickling water provides nutrients and adequate moisture for the plants and root system to thrive. Recycling the water in this closed loop system is much more resource efficient than the constant spraying and watering required by soil-based plant walls.
Indoor Air Quality
Nedlaw Living Wall Biofilters are the most rigorously tested living walls in the world. They are here to do a job, and that job is increasing building performance while looking fantastic. Our walls are considered “active” because they pull polluted air through the room system. Both active and passive walls feature root environments, but passive walls work very slowly.
Plants alone do very little to improve air quality. The root zone is the biofiltration zone. We are working to continuously improve the efficiency of VOC removal in order to maximize the clean air our system provides.
Since they are engineered for optimal filtration, our Biofilters can clean 100 square feet of interior space (assuming average floor height) with every square foot of living wall. To put that in real terms, consider that the 3 ft x 7 ft Biofilter in our board room, connected to the HVAC, is cleaning the air for 2,100 square feet of office space. It is metabolizing the smell of microwaved lunches, off-gassing furniture, bathrooms, the truck garage next door and the farms down the road. Odour removal is a great perk!
Energy savings
The way in which our biofilters reduce a building’s energy load is quite simple. We offer an alternative fresh air source; so rather than drawing air from outside which needs to be heated or cooled, our Biofilters help you bypass that requirement. Connecting the Biofilter to the HVAC system creates the most efficient system, adding only a very small draw to pull the air through the wall. That said, we build many Biofilters with on-board fans that can also pull air through the system.
We design the Biofilter to work effectively in your space – for the job that it needs to do. We work closely with you to meet your performance goals with a custom-designed Biofilter that is as unique as your building. Whether your project is new construction or a retrofit, get us in early on the planning so we can maximize the efficiency, and results, of the system!
Contact us today if
you are ready to discuss!
In 2015, we conducted a North American study using RETScreen Building Performance software to determine the cost savings of generating 100 litres per second of clean air with a Biofilter compared to bringing that volume of air in from the outside (and conditioning it) over an entire year. We ‘valued’ that volume of air, using regional energy rates for both heating and cooling; that value or cost, is what you save by using a Biofilter. This study also provided data on carbon savings. The document link below is a summary of this study, although we’d be happy to discuss with you the anticipated savings for your project.
