Five Strategies That Can Reduce the Impact of Healthcare Buildings on the Environment
When most people hear the word ‘sustainability,’ with architecture their focus immediately goes to visible building components such as green roofs or solar panels, and their assumption is that sustainability costs a significant amount of ‘extra’ funds. As architects, we shouldn’t be asking healthcare providers if they want a sustainable building; we should be designing buildings that perform well and help the building occupants achieve their best. As we start to understand the client’s goals, we can determine where our effort will provide the most value. While renewable energy sources such as solar panels or geothermal heating and cooling will play a vital role in environmental impact and getting to a net zero energy building, there are many aspects that go into a high performing, sustainable building. Here are five strategies to consider as you begin planning your next healthcare facility.
Sustainability Strategy #1: Adaptive Reuse
The ‘greenest’ building is often the one that already exists. Many of the healthcare projects we work on involve some level of architectural renovation to an existing space, but more and more we are being asked to re-purpose or adapt a building for healthcare use. Although this can offer challenges around layout and varying MEP needs, it allows us to reuse an existing structure and avoid the additional embodied carbon that new steel and concrete structures add to a project. As an added benefit, many of these projects are already in established neighborhoods and the projects bring useful services and care close to home while enhancing storefront activity on our streets. Two recent EUA urban adaptive reuse examples are the Ascension Shorewood Clinic, a former (and locally iconic) grocery store and the Ascension Third Ward Clinic, originally a firehouse and most recently a retail store. It is important when adapting or renovating an existing space, to do a whole building assessment and have the building retro-commissioned to understand how the building and MEP systems are performing. This step determines what upgrades should be included to allow the building to perform well as a healthcare facility.
Sustainability Strategy #2: Site design
If you aren’t looking to reuse or renovate and are building new, one of the first design decisions will be determining the placement of the building on the site. In a clinic where there is a regular flow of traffic in and out of the building, the entrance can play a big role in determining the comfort of the interior space as well as unnecessary added heating and cooling costs. Ideally the entrance is oriented away from prevailing winds, but if this isn’t viable due to site constraint, then prioritizing the size and shape of the vestibule can help separate the exterior and interior environment. Another aspect of site placement is determining views and daylight potential, as well as orientation of glazing to avoid unnecessary glare and heat gain.
Outside of the building footprint, it is important to think about the landscaping and how storm water will be collected to avoid run-off. On a recently completed project, only 20% of the site was usable due to wetlands, setbacks and floodplain restrictions. Our team had to get creative when planning how to drain water from the building’s roof in order to avoid any wetlands. The solution included both a bio retention garden and a wet pond or retention basin to handle the water on site.
Sustainability Strategy #3: Energy use reduction
If healthcare were a country, worldwide it would be the fifth largest emitter on the planet, with US healthcare being the highest contributor to the industry as a whole. My firm has signed the American Institute of Architects ─ AIA 2030 Commitment with the goal of designing net zero energy buildings by the year 2030. We use software to prioritize energy performance and tracking tools to measure our progress.
In healthcare, the HVAC system contributes about 70% of the total energy use in an average hospital; much of this is because many of the spaces require a high number of air changes per hour. There are several strategies that are viable for hospitals and clinics to help reduce the overall energy consumption.
First, when selecting systems, it is important to select high efficiency HVAC systems and consider the cost/benefit of an energy recovery system. When it comes to providing ventilation and temperature control to a space, consider when the space will not be occupied and turn back the air changes per hour as allowed per ASHRAE 170. This can be done with occupancy sensors or demand-controlled ventilation which is reliant on CO2 sensors in a space. Due to COVID-19 this may not be immediately feasible, but buildings should be including it in their design for future flexibility post-pandemic. Another opportunity is to carefully design the quantity and location of glass on the exterior of the building; choosing triple glazing for the façade often eliminates the need for perimeter heating throughout the building, allowing savings to be applied towards improved glazing and further energy cost savings. Lastly, consider a geo-thermal system and the viability of solar panels to further reduce the building’s total Energy Use Intensity (EUI).
Sustainability Strategy #4: Indoor Environmental Quality
The indoor environment of buildings plays an extremely important role in the health and well-being of its occupants. One study in particular, the CogFx study, looked at how factors such as VOC (Volatile Organic Compounds), outdoor air ventilation and levels of CO2 can affect how occupants perform within a space. The study concluded that those who work in “green” buildings achieved higher performance on a series of cognitive tests. A common contributor to VOCs in the indoor environment is the material selected for the interior, such as floor coverings, upholstery on furniture and wall finishes. Another aspect is how we ventilate our buildings, a subject that has gained more attention with the onset of the COVID-19 pandemic. In general, healthcare buildings achieve good scores for ventilation because of the requirements set by ASHRAE 170, but as mentioned above, when renovating an existing building it is extremely important to do a building assessment and complete retro-commissioning to understand how the existing mechanical systems of a building are performing.
We spend 90% of our time indoors and we also know that employers spend 90% of their costs on their employees. That alone, should convince us to dedicate more money and thought on the indoor environment.
Sustainability Strategy #5: Lighting
Lighting is typically thought of as an interior consideration, but is also important for the exterior of a building as light pollution can impact plant and animal life, as well as neighboring buildings and communities. For exterior lighting design it is prudent to select fixtures that are both efficient, but also prevent light trespass, when light is cast beyond where it is needed for safety and security.
On the interior, when thinking about sustainable lighting, first start with studying daylight in a space and determining which areas can be primarily day-lit before considering artificial lighting. While studying daylight, it is important to also consider glare, which can impact the comfort level of individuals within the space. At EUA, we utilize Cove.Tool which allows us to analyze both daylighting and glare and also helps us understand which spaces are over lit and therefore need another means to control daylight such as exterior shading devices, interior window treatments or glazing with less visible light transmittance.
Once the building has been designed for ample daylight, we can turn to electric lighting. By first understanding the use of the programmatic spaces it will determine what type of lighting is the best solution. For example, in an exam or treatment space, overhead lights directly over an exam table should be avoided to minimize discomfort for patients. However, in offices, a mix of overhead and task lighting allows the users to control the lighting of the space to their comfort. Dual technology occupancy sensors should also be installed in all rooms to avoid lighting spaces when unoccupied. For a recent outpatient project, Froedtert West Bend Health Center, we implemented an enhanced wireless lighting control system that is integrated with the building automation system and can monitor occupancy and control both lighting and mechanical systems based on occupancy. The system allows the owner to fine tune their building so it functions better for the occupants and saves energy in the process.
These five strategies are only a handful of sustainable approaches that can be considered for new healthcare construction and renovation. Each project has its own unique set of challenges and goals, but I believe architects can make a positive impact on the environment and the people within the space through designing high performance buildings. I am passionate about sustainability, so please feel free to reach out to me on LinkedIn and ask me questions and provide your experience to keep the sustainability conversation going.