There will be minimal additional costs for this credit if open space was already planned. If the team was not planning on including open space, or was only planning a limited area, then adjusting the building footprint could result in a cost increase or less buildable square footage.
Adding a green roof to meet this credit could be costly, but it will help with many other LEED credits and green building strategies. (See LEEDuser’s green roofs strategy page for more detail.)
Designing a project with ample open space can increase the value of the property and may increase rents, especially in areas that do not generally provide these amenities to building occupants. From a purely economic standpoint, however, buildable square footage typically adds more value than open space.
Additional costs may be incurred if you need to buy modeling software or hire a qualified engineer to perform this assessment. Unless this assessment was performed and documented during the design phase of the building, it’s unlikely that the costs to retroactively perform the assessment are worth pursuit of this credit, since it would not generally be feasible to change the natural ventilation system design in an existing building just for the purposes of this credit.
Additional costs may be incurred if you need to hire a qualified engineer to perform this assessment. Unless this assessment was performed and documented during the design phase, it’s unlikely that the costs to retroactively perform the assessment are worth pursuit of this credit.
Increasing the amount of fresh air in your building may also have positive impacts on health and productivity of employees. There have been a number of studies that linked indoor environmental quality with occupant health and productivity—see Resources.
Energy-efficient design can increase your construction budget. Use your computer model to optimize packages of upgrades that balance any added costs against cost savings, and run payback analyses to identify the most cost-effective options.
