More fresh air means healthier buildings. Building on IEQp1: Minimum Indoor Air Quality Performance, this credit calls for exceeding by 30% the minimum outside air requirements set by ASHRAE 62.1-2007. Our indoor environments are burdened by carbon dioxide produced by occupants and by off-gassing of construction materials and furnishings. These conditions can cause fatigue and contribute to occupant health problems. Increased ventilation is one way to mitigate these problems.

There may be some tradeoffs

Your mechanical system may already be designed to accommodate increased ventilation, but in other cases, this credit may represent a tradeoff in energy consumption (conditioning more air along with increased fan power to distribute it), and may reduce the overall energy consumption measured in EAc1: Optimize Energy Performance. Projects that use displacement ventilation, including underfloor air distribution, are often able to achieve the credit with minimal increase in energy use. Demand-controlled ventilation systems are also a good way to minimize the energy cost, and also work well with IEQc1: Outdoor Air Delivery Monitoring.

Can be tough with natural ventilation

For projects relying on operable windows to provide fresh air, this credit is largely unattainable because you cannot usually guarantee a 30% increase in fresh air without mechanical means. However, projects using natural ventilation do have a compliance path and a reference standard they can use to attempt compliance. Increased ventilation in general as well as natural ventilation strategies are best implemented in mild, relatively dry climates where relatively little energy is needed to condition outside air.