How do you calculate the site coverage ratio for a commercial building?

1 What is the SCR formula?

The SCR formula is based on dividing the total building area by the total site area, and multiplying by 100 to get the percentage. The total building area is the sum of the horizontal areas of all floors, including any basements, mezzanines, or attics. The total site area is the area of the land parcel that is allocated for the project, excluding any public rights-of-way, easements, or buffers. The formula can be expressed as: SCR (%) = (Total building area / Total site area) x 100

2 Why is the SCR important?

The SCR is important because it reflects the degree of development and utilization of the site, and it may have implications for the environmental performance, visual appeal, and functional suitability of the project. For example, a high SCR may indicate a high-density and compact development, which could reduce the land consumption, energy use, and greenhouse gas emissions of the project, but it could also create issues with stormwater management, natural ventilation, daylighting, and landscaping. A low SCR may indicate a low-density and sprawling development, which could provide more open space, greenery, and flexibility for the project, but it could also increase the infrastructure costs, transportation impacts, and land fragmentation of the project. Therefore, the SCR should be balanced with other factors such as the site context, the building design, and the project objectives.

3 How to measure the building area?

To measure the total building area, you need to calculate the horizontal areas of all floors, including any basements, mezzanines, or attics. The horizontal area of a floor is the area enclosed by the outer surface of the exterior walls, or the centerline of the common walls with other buildings. The horizontal area should include any projections or overhangs that extend beyond the exterior walls, such as balconies, canopies, eaves, or columns. The horizontal area should exclude any voids or openings that are not enclosed by walls, such as courtyards, atriums, or skylights. You can use a scale ruler, a measuring tape, or a digital tool to measure the horizontal areas of each floor, and then add them up to get the total building area.

4 How to measure the site area?

To measure the total site area, you need to determine the area of the land parcel that is allocated for the project, excluding any public rights-of-way, easements, or buffers. The land parcel is the legal unit of land that is owned or leased by the project owner or developer, and it may have a defined boundary, shape, and size. The public rights-of-way are the portions of the land that are dedicated for public use, such as streets, sidewalks, alleys, or trails. The easements are the portions of the land that are granted for specific purposes, such as utilities, drainage, or access. The buffers are the portions of the land that are required to be left undeveloped or landscaped, such as setbacks, riparian zones, or buffer strips. You can use a plat map, a survey plan, or a GIS tool to measure the area of the land parcel, and then subtract the areas of the rights-of-way, easements, or buffers to get the total site area.

5 How to apply the SCR formula?

To apply the SCR formula, you need to divide the total building area by the total site area, and multiply by 100 to get the percentage. You can use a calculator, a spreadsheet, or a software program to perform the calculation. For example, suppose you have a commercial building with a total building area of 12,000 square feet, and a total site area of 20,000 square feet, excluding any rights-of-way, easements, or buffers. The SCR would be: SCR (%) = (12,000 / 20,000) x 100 SCR (%) = 0.6 x 100 SCR (%) = 60 This means that the building covers 60% of the site area, leaving 40% of the site area as open space or landscaping.

6 What are some SCR standards and guidelines?

The SCR may vary depending on the type, location, and purpose of the commercial building, and it may be regulated by some standards and guidelines. For example, some zoning codes may specify the maximum or minimum SCR for different land use categories, such as office, retail, industrial, or mixed-use. Some green building rating systems may award points or credits for achieving certain SCR levels, such as LEED, BREEAM, or Green Star. Some design guidelines may recommend optimal SCR ranges for different site conditions, such as urban, suburban, or rural. Some best practices may suggest appropriate SCR values for different sustainability goals, such as energy efficiency, water conservation, or biodiversity enhancement. You should consult the relevant standards and guidelines for your project, and compare your SCR with the benchmarks or targets.

7 Here’s what else to consider

This is a space to share examples, stories, or insights that don’t fit into any of the previous sections. What else would you like to add?