St. George lets a one-story accessory building sit right on the rear lot line, up to 20 ft tall. Here are the rules and what a steel shop costs in Washington County, where light snow keeps prices down.
| St. George at a glance | What it means for your building |
|---|---|
| Permit needed | The code refers to accessory buildings of 200 sq ft or less that do not need a building permit. Larger buildings need one (apply through CityInspect). |
| Rear yard | One story, up to 20 ft. Can sit 0 ft from the rear and side lot lines, but at least 20 ft from any street and 6 ft from other structures. Must not drain stormwater onto neighbors. |
| Side yard | Outside the required setbacks, 6 ft from other structures, up to 20 ft, and must match the house: same materials, colors, roof pitch and design. |
| Timing | An accessory building cannot be built or used before the house is occupied (barns in agricultural zones are exempt). |
| Easements | Building over a utility easement needs written approval from the joint utility commission. |
| Agricultural zones | A-0.5 to A-20: same 20 ft and 6 ft limits for non-farm buildings; barns must be 50 to 100 ft from any home. |
| Elevation | About 2,530 ft, Washington County. Much lighter snow load than the Wasatch Front. |
From St. George's published code and permit pages, checked October 2026. Rules change, so confirm with the city before you build. Snow, wind and seismic values: see the Washington County guide.
Building package estimates for Washington County from our live estimator (October 2026, 3:12 roof, 10×10-class roll-up doors). Foundation, site prep and erection are separate.
| Building | Washington County estimate |
|---|---|
| 24×30×12 garage or small shop | $15,500 – $19,200 |
| 30×40×14 shop, 2 roll-up doors | $26,800 – $33,300 |
| 40×60×16 shop, 2 roll-up doors | $53,500 – $66,600 |
Your written quote is the firm number. More on steel shop pricing in Utah →
Because a rear-yard building can sit on the lot line, a steel shop in St. George can use more of a typical lot than in most Wasatch Front cities. If you want it in the side yard instead, plan for siding, colors and roof pitch that match the house; we can match roof pitch and colors in the design.
We found no separate size cap for accessory buildings in the single-family zones, but the zone setbacks and height still apply. Tell us your lot and we will size it.
61 S Main St, St. George, UT 84770 · 435-627-4100. City permit page →
A one-story accessory building in the rear yard can sit 0 feet from the rear and side lot lines, but must be at least 20 feet from any street and 6 feet from other structures.
Up to 20 feet and one story for accessory buildings in the single-family zones, in both the rear and side yard.
Only if it sits in the side yard. Side-yard accessory buildings must use the same materials, colors, roof pitch and design as the house.
A 30x40 shop with 14-foot walls and two roll-up doors estimates at about $26,800 to $33,300 for the building package in Washington County on our live estimator (October 2026), lower than the Wasatch Front because of lighter snow loads. Foundation and erection are separate.
Get a live estimate now, then a firm quote with drawings engineered for your address.