Methodology & assumptions

Fence Planner is a free planning and materials-estimation tool. It is not a fence installer, engineer, surveyor, permit office, utility-locate service, or product manufacturer. Results are planning estimates you can reproduce from documented formulas and editable settings.

How this guide content is prepared

Calculator behavior is traced to source code and covered by automated tests. Official sources are cited when a guide discusses permits, utilities, or product requirements. Hypothetical reference examples are labeled as such. AI assistance may be used for drafting; claims and calculations require human review against the live tool before publication. Attribution: Fence Planner.

Plan run length

Plan run length is measured along the proposed fence centerline between endpoint markers on the plan. It is not a legal survey boundary and not an outside-to-outside installed dimension.

Panel modules and pitch

Two stored modes are available:

Panel itself (panel_only, default): entered width is the panel; calculated pitch = panel width + post face (default 96 in + 4 in = 100 in).
Complete module (includes_post): entered width is already the repeating pitch.

The planner shows the calculated pitch beside these controls. Fill is divided per gate-free segment. When a remainder above 0.5 in creates a cut bay, the shopping list reports both the pitch remainder (center-to-center distance left after full modules) and the calculated clear panel space (pitch remainder minus one full post face for equal square posts). That clear space is not a guaranteed field cut width — product fitting allowance still applies. Cut bays are still purchased as whole stock panels.

Gates and fill

Planned gate opening width is removed from fence fill and splits a run into fill segments. It is not modeled as leaf width, kit width, or guaranteed finished clear passage. Swing direction is visual in Dream View only.

Posts and shared joints

Posts are classified from geometry: line, corner, end, gate, terminal (chain-link), and structure. Shared joints are counted once. When roles coincide, priority is gate > corner > end > structure > terminal > line.

For panel systems, every purchased bay has posts at both ends. If a cut remainder creates an extra bay, a post is placed at the last full-module boundary before that cut (for example, at 900 in on a 960 in run with a 100 in module).

Structure connections exist in project data and exclude a purchased / concreted post, but Plan View does not yet provide a control to create them interactively.

Wood and chain-link spacing

Site-built wood and chain-link use editable on-center post spacing (defaults 8 ft wood, 10 ft chain-link).

Concrete

Volume per post = cylindrical hole − square post displacement. Project total is rounded up once to whole bags. Hole diameter, depth, post face, and bag yield are editable in the planner and on the concrete calculator. The 0.33 cu ft value is a planning default — enter the yield printed on your product. Optional concrete waste is off by default.

Waste

Default waste percentage is 5%. By default it applies to pickets/rails (and related wood fill) and not to panels or concrete. Fastener pack rounding may still use the waste percentage. This is not a cutting-stock optimizer.

Materials cost estimates

After quantities are calculated, Fence Planner can show an indicative materials cost range for the United States (USD) or Canada (CAD). Totals use dated retail observations and substitution / conversion fallbacks when an exact local SKU is missing. Currencies are never mixed. You can override any unit price; your override wins. Estimates exclude tax, delivery, labor, permits, tool rental, and site work unless you add them. They are not live retailer quotes or inventory checks—confirm prices at your store before buying. Freshness labels and match warnings appear in the shopping list when a price is approximate, converted, or stale.

Chain-link

Calculated: fabric fill after gates, fabric rolls, top-rail sections, ties, line and terminal posts, tension-wire flag, estimated tension bars / brace bands, and gate hardware. Not a complete fittings catalog (for example loop-cap and brace-rail SKUs are not fully modeled).

What the tool does not do

Slope / stepped / racked geometry
Curves
Frost-line lookup
Utility locate or digging clearance
Legal property boundaries
Structural engineering
Live store quotes or real-time retailer inventory (regional estimate bands only)
Arbitrary user share URLs (predefined example loaders only)

Reference scenarios

Predefined hypothetical examples (FP-RS-01, 02, 03, 05, 06) can be loaded from the planner with an explicit confirmation. They never overwrite your plan merely because a URL was opened. Slope scenario FP-RS-04 is not representable. Scenarios are covered by automated tests.