What is the minimum lot size to build a house in Orion Township?

By district (Section 5.04; Section 6.04; Article XXVI):

• SF: 2.5 acres, 165 feet wide
• SE: 1.5 acres, 165 feet wide
• SR: 30,000 square feet, 120 feet wide
• R-1: 14,000 square feet, 100 feet wide
• R-2: 10,800 square feet, 80 feet wide
• R-3: 8,400 square feet, 70 feet wide

The R-2 and R-3 figures assume public sewers. Without sewers, the ordinance sets 12,500 square feet, and it warns in the same breath that Oakland County Health Department rules requiring 1 acre for a well and septic parcel supersede that number unless you obtain written Health Department approval (Section 6.04, footnote, amended 10.20.25). For unsewered land, the county standard is the practical control.

Two safety valves: a lot of record platted before the ordinance may be built on regardless of size if everything else complies, and two adjoining undersized lots in common ownership merge into one for zoning purposes (Section 27.03.A).

Each district also sets a minimum house size, from 960 square feet in R-3 up to 1,500 in SR (Section 5.04; Section 6.04). Verify sewer availability with the township before pricing land.