Before beginning any construction project, zoning approval must be obtained. Zoning approval signifies that the property is properly zoned for the proposed construction and that the location of the structure is within the legal limits of the property lines.

If the construction project is located in a municipality, contact that municipality for zoning approval. Construction projects located in unincorporated St. Louis County will receive zoning review by St. Louis County, Department of Public Works.

A site plan (plot plan) must be drawn to scale and must clearly depict the dimensions and angles of the lot boundary lines. The site plans must also include:

  Location and dimensions of any existing structures and their distance from the property lines and from each other;

 The direction of the slope or drainage is indicated on the site plan by arrows;

 The ground elevations and the elevation of the top of the foundation of the structure(s);

 Location and width of easements (Easements give access rights to Utility Companies and other duly-authorized agencies), thus building within a dedicated easement is restricted;

 Septic fields (if the property is presently on a septic system).

All commercial projects must submit 4 site plans that are sealed by a Missouri registered architect or engineer.

Home owners applying for a permit must also submit 4 site plans, however, the site plans do need to be sealed.

Home owners drawing their own construction plans, may obtain a copy of their site plan from:

 The survey of your house at the time you purchased the property;

 The Title Company that closed the sale of your house;

 The building permit for your house;

 The St. Louis County, Assessor's Plat Book maps. The plat book locates several parcels on one page. The plat book parcels include the lot dimensions, however, the existing structures are not indicated on the parcel. These plat book copies can be used as a guide to help draw a scaled plot plan.