While green buildings must be energy efficient, they must also create a healthy indoor environment for building occupants. Our building designers seek integrated design solutions which achieve both of these potentially competing priorities as well as harnessing wind as a natural resource.
Dedicated Outdoor Air System (DOAS)
DOAS systems separate cooling and ventilation loads, providing tempered, dehumidified 100% outside air while facilitating the decoupling of sensible and latent loads to both reduce energy use and improve indoor air quality. Designed properly, DOAS systems can provide lower first costs as well as operating costs. LAS has successfully incorporated DOAS on a variety of project types ranging from research labs to commercial offices and student housing.
Computational Fluid Dynamics Analysis (CFD)
Computational Fluid Dynamics, or CFD, is a tool that helps predict the movement of fluids both internal and external to the designed building. Building Performance Analysts use this tool to help evaluate natural ventilation or HVAC design strategies and their impact on occupant comfort. After the geometry and boundary conditions have been established, CFD can analyze the internal conditions for a typical or worst case design scenario and simulate the wind flow around the building or site. The beauty of CFD is that it can be utilized in the early design stages to improve both design accuracy and efficiency as part of the integral design process.
Operable windows and natural ventilation strategies were traditionally used to provide cooling and improve thermal comfort prior to the widespread use of energy-intensive air conditioning. At the LEED Platinum certified Southface Eco Office, operable windows with insect screens allow natural ventilation during Atlanta’s moderate spring and fall days. The National Park Service’s LEED Gold certified Twin Creeks Science and Education Center features motorized clerestory windows to exhaust hot air. The LEED Gold certified visitors center at the Grand Bay National Estuarine Research Reserve features operable windows throughout as well as porches with traditional deep overhangs and screened classroom and research spaces.