Calculate lot coverage percentage, allowed building footprint, or required lot area with square feet, square meters, acres, and hectares.

Lot Coverage Formula

The following formula is used to calculate the lot coverage percentage.

LC = BA / LA \times 100

Where LC is the lot coverage percentage
BA is the total non-overlapping horizontal footprint area counted under the applicable local definition, not the sum of every floor.
LA is the total lot area

To calculate lot coverage, divide the total building area by the total lot area, then multiply by 100.

Lot Coverage Definition

Lot coverage expresses the horizontal area counted under local zoning rules as a percentage of the defined lot area. For this physical footprint model, a calculated value above 100% means the entered counted area exceeds the entered lot area; check units, double-counted areas and floor area entered as footprint. This ratio cannot establish boundary encroachment.

Example Problem

How to calculate lot coverage?

First, determine the total lot area.
In this example, we are looking at a waterfront property along the New Jersey coast. The total lot area is found to be 10,000 square feet (ft^2).
Next, determine the area of each individual building on the lot.
There are 3 buildings found on this lot with areas of 1,000, 4,000, and 1200 square feet respectively.
Next, add all of the building areas together into one total building area.
This yields a total area of 6,200 square feet.
Finally, calculate the lot coverage ratio.
Using the formula L = BA/LA *100, the lot coverage is found to be 6,200/10,000 * 100 = 62%.

FAQ

What is included in lot coverage?

The applicable local definition determines what is counted. Buildings, pools, driveways, decks and other features may be included or excluded; building coverage and impervious-surface coverage may be separate measures. Use your jurisdiction's counted areas and lot-area definition.

Is lot coverage the same as floor-area ratio?

Lot coverage is the ratio of the total building footprint to the total lot area, while the floor-area ratio is the ratio of the total area of all floors of a building compared to a lot.

In the case of floor-area ratios, the ratio is often higher than 1 or 100% because there are multiple floors on a single lot area.

What is the maximum lot coverage?

Use the coverage limit in the applicable local rules. The calculator compares areas against the percentage you supply; setbacks, easements, height, floor-area ratio and other requirements may further restrict a project. A result at or below the supplied limit does not establish zoning approval.