Setback & Sight Triangle Calculator
Setbacks by zone type · Corner lot triangle · Right-of-way estimator · Printable worksheet
The sight triangle on a corner lot is the area near the intersection that must stay clear for driver visibility. Enter your street measurements to calculate the triangle dimensions and maximum fence height within it.
The right-of-way (ROW) is the strip of public land adjacent to the street. Your fence must be inside the ROW boundary — not in it. This estimator helps you figure out where the ROW line likely is.
Fill in your measurements below, then print this worksheet to bring to your building department or use while staking your fence layout.
Property Information
Measured Setbacks (from property line)
Fence Specifications
Corner Lot (if applicable)
Understanding Fence Setback Rules
A setback is the minimum required distance between your fence and a property boundary, public right-of-way, or easement. Setbacks are set by your local zoning ordinance — not state law — which means they vary by county and even by zoning district within the same county.
The Four Setback Distances That Govern Every Fence
| Boundary Type | Typical Setback | Who Sets It | Common Exception |
|---|---|---|---|
| Rear property line | 0 ft (on the line) | Local zoning | Drainage easements may require 5–10 ft buffer |
| Side property line (rear half of lot) | 0 ft | Local zoning | HOA may require 2–3 ft setback |
| Side property line (front half of lot) | 0–5 ft | Local zoning | Fire access corridors may require 3 ft minimum |
| Front property line / ROW | At property line (fence must be behind ROW) | Local zoning + public works | ROW is often 5–15 ft behind curb — measure from the ROW line, not the curb |
| Corner lot sight triangle | No fence over 2.5–3 ft within triangle | Local traffic engineering | Triangle size varies by street speed: 20–50 ft from intersection |
| Utility easement | 0 ft (fence allowed in easement) | Easement terms | Utility company may remove without compensation; drainage easements often prohibit fences |
⚠️ The #1 Setback Mistake
Most homeowners measure their front yard fence setback from the curb or edge of sidewalk. The correct measurement is from the property line — which in most neighborhoods sits 5 to 15 feet behind the curb. A fence built to the sidewalk edge is almost certainly in the public right-of-way and will be cited for removal.
How to Find Your Property Lines Without a Survey
- Check your county GIS parcel map — Search "[your county] GIS parcel map" — most counties offer free online parcel viewers that show property boundaries overlaid on satellite imagery.
- Look for iron pin survey markers — Licensed surveyors place iron rebar pins (often with colored plastic caps) at property corners. Search at the corners of your lot with a metal detector if needed.
- Call your county public works department — Ask for the right-of-way width on your street. They can tell you exactly how far the ROW extends from the street centerline.
- Use your closing documents — Your deed and title survey from when you purchased the home show the property boundaries. The plat map shows your lot within the subdivision.
- Hire a surveyor for tight situations — If your planned fence is within 2–3 feet of where you think the property line is, a licensed survey ($300–$900) is always cheaper than relocating a completed fence.
Free: Fence Permit Application Checklist (PDF)
Includes the complete setback measurement worksheet and a corner lot sight triangle reference card.
⬇ Download Free PDFFrequently Asked Questions
In most jurisdictions, yes — for rear and side yard fences. A 0-foot setback means the fence may be placed directly on the property line. However, you should confirm the actual property line location with iron pin markers or a survey before placing posts. Building even a few inches onto a neighbor's property is an encroachment. It's also courteous (and sometimes required by local ordinance) to give your neighbor advance notice before building on the shared line.
The ROW line is typically 25–33 feet from the center of the road — meaning in a standard 50-foot ROW, the line is 25 feet from center. On a typical residential street, the ROW extends 5–15 feet behind the back of curb. Call your county public works department and ask: "What is the right-of-way width on [street name]?" They'll give you the distance from centerline, which you can measure from the center of the road. Your county's GIS system often shows ROW lines too.
A sight triangle (also called a "clear sight triangle" or "visibility triangle") is the area at a street intersection that must remain clear of obstructions so drivers and pedestrians can see each other. On residential streets with stop signs, the triangle is typically 15–25 feet along each curb line from the intersection. Within this triangle, most jurisdictions limit fences to 2.5–3 feet maximum height. Corner lot homeowners must identify this triangle before designing any front-yard or street-side fence.