Building Envelope Calculator

See how much of your lot you can actually build on. Uses zoning setbacks from your prework report.

Lot Dimensions

Lot width / frontage (m)

Lot depth (m)

Setbacks

Front setback (m)From your zoning section

Rear setback (m)

Left side setback (m)

Right side setback (m)

Additional Restrictions

Riparian setback (m)30m if fish-bearing stream on boundary

FAR / FSRFrom zoning (0 = no limit)

Max height (m)

Max lot coverage (%)0 = no limit

Reading your prework report

Your report's Zoning section shows the setbacks, FAR, and height limits for your zone. Plug those values directly into the fields above. Key things:

Front/rear/side setbacks are in the zoning development rules table
FAR (Floor Area Ratio) limits total floor area to a fraction of lot area. FAR 0.4 on a 1000m2 lot = 400m2 max floor space.
Riparian setback applies if your property borders a watercourse (check Regulatory section)
Lot coverage is different from FAR. Coverage = footprint only. A 2-storey house uses half the coverage for the same floor area.

This is a planning tool. Confirm all setbacks with the local planning department before design. Additional setbacks may apply for wells, septic fields, and environmental development permit areas.