Open-Grid Paving

Concrete has higher SRI values than asphalt and so is preferable for this credit. However, it is also generally more expensive than asphalt, but it is more durable and often has a lower life-cycle cost, as it must be replaced less often. This is especially true in high-traffic areas, turnarounds, and areas of heavy-duty vehicle use. If concrete can’t be used everywhere due to the price, use it selectively in high wear-and-tear areas.  

Power-washing old concrete can help restore it to near-new SRI values. For the purposes of documenting the credit, it is assumed that the material has the new value, unless existing hardscape is being used. For existing hardscape, you must either use the weathered value, or document that surfaces have been cleaned and lightened enough to be equivalent to the default SRI values.

For concrete and asphalt, you can use the following default SRI numbers from the LEED Reference Guide:

Obtain the SRI value of materials you are considering from the manufacturer.

SRI is the measure of a material’s ability to reject solar heat and is determined by a material’s light reflectance and heat admittance. For example, dark colors have values close to 0 SRI absorb most of heat they receive, while lighter colors have higher values and tend to reflect heat.

Explore integrating the use of light-colored hardscape material with an SRI value of at least 29.

Light-Colored Materials

PV canopies will have more of an upfront cost (that can often be offset with government incentives), but is a great way to install renewable energy onsite, contributing to EAc2: Onsite Renewable Power, without losing the functionality of your parking.

Installing freestanding canopies can be very cost-effective and will require little maintenance in the long run.