8 Sept 2023
We are looking at different strategies and technologies architects can utilize to dramatically increase water efficiency in residential and commercial buildings.
Water is one of our most precious resources. As populations grow and climate change leads to water scarcity in many parts of the world, it is more important than ever to use water wisely, especially in the built environment.Â
For architecture and construction firms looking to design sustainable, efficient buildings, water usage should be a top priority.
In this article, we’ll look at different strategies and technologies architects can utilize to dramatically increase water efficiency in residential and commercial buildings. By implementing these water-saving measures, architects can create structures that are environmentally friendly and future-proofed against water shortages.
Reduce Water Use for Plumbing Fixtures
One of the easiest ways to cut water usage in a building is to install high-efficiency plumbing fixtures designed for conservation. For example:
Low-flow toilets - Toilets account for nearly 30% of an average household's indoor water use. Replacing old models with water efficient model-approved toilets that use 1.28 gallons per flush, versus older models that used 3.5 gallons, can reduce usage by over 60%. Dual-flush toilets with separate buttons for liquid and solid wastes optimize water use even further.
Low-flow faucets and showerheads - Installing faucets and showerheads with flow rates under 2.0 gallons per minute can reduce water waste by 30% or more compared to standard models. Look for water efficient-labelled models that spray efficiently without sacrificing performance.
Water-efficient dishwashers and washing machines - Choosing ENERGY STAR certified appliances can cut water use significantly. Front-loading washing machines, in particular, use about 30% less water than top-loaders. Look for models with various wash cycles and water levels to optimize water use.
Touchless faucets - Hands-free electronic faucets with infrared sensors prevent taps being left on accidentally. They use very small amounts of water per use cycle.
Install Greywater Reuse Systems
Greywater is gently used water from bathroom sinks, showers, tubs, and washing machines. By installing greywater systems to capture and reuse this water onsite for toilet flushing or irrigation, buildings can greatly reduce their potable water usage.
Simple systems divert greywater into the toilet tank, while more complex pumped set-ups filter and disinfect greywater for wider applications like subsurface landscape irrigation. While greywater cannot be used for drinking, it works very well for flushing toilets and urinals. Costs of greywater systems are recouped through water savings in 3-5 years.
Collect Rainwater
Rainwater harvesting captures, stores, and uses rainwater for onsite irrigation or other non-potable uses. Systems can be very simple, consisting of rain barrels or cisterns that sit under gutter downspouts. Larger systems utilize pumps, filtration, and storage tanks to supply rainwater for activities like landscape watering, vehicle washing, or HVAC cooling tower use.
Collected rainwater reduces the need to use treated drinking water for non-essential purposes. Architects should evaluate roof size and local rainfall patterns when designing rainwater harvesting systems. While upfront costs are higher, long term savings on water bills make these systems a smart investment.
Use Drought-Tolerant Landscaping
For any landscaping, selecting native plants with low watering needs for the local climate can drastically cut irrigation requirements. Xeriscaping utilizes drought-resistant plants, rocks/gravel, and efficient irrigation to create attractive, low-maintenance landscapes that thrive on little water.
By choosing plants suited to the environment, landscape water needs can be reduced 50-75% versus grass lawns. Smart controllers and drip irrigation ensure water is only used when and where it's needed. Good drainage is key for preventing disease. Proper soil preparation and mulching hold moisture.
Install High-Efficiency HVAC Systems
Heating, ventilation, and air conditioning (HVAC) systems can use a lot of water through cooling towers, humidification, and boiler systems. By upgrading to air-cooled HVAC chillers, buildings can eliminate water usage for cooling. These systems transfer heat directly to the outdoor air.
Installing low-flow controls on steam boilers and choosing alternative humidity technologies like ultrasonic or impingement humidifiers over evaporative humidification also conserves water. Newer HVAC technologies allow tight regulation over water flows for optimization.
Monitor Water Usage with Sensors
Smart sensor technology allows building owners and facilities managers to track real-time water usage and detect leaks. Analytics provide insight on wasteful behaviors or maintenance issues.
Sensors on equipment like cooling towers can optimize chemical treatments and blowdown practices for water efficiency. Flow meters help identify spikes in usage that indicate leaks or other problems. The Internet of Things and data analysis allow tighter control over building water management.
Conclusion
With climate uncertainties and growing populations putting more pressure on limited water supplies, designing buildings for maximum water efficiency is crucial. Sustainable architecture firms can utilize plumbing fixtures, greywater systems, rainwater harvesting, drought-tolerant landscaping, efficient HVAC, and sensor technologies to create smart, water-saving buildings.
Investing in water conservation not only benefits the environment but also cuts utility and maintenance costs for owner’s long term. Water-wise design and technology should be standard practice for all new construction and retrofits. With an integrated approach, we can cultivate a sustainable built environment.