US FENCEPROJECT PLANNER

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Every number has an assumption.

The planner estimates quantities from your dimensions. It does not select a safe structural design or certify a construction project.

Version 2.0 · updated October 24, 2026

1. Layout, bays and shared posts

A run is measured between its endpoint post centers in decimal feet. Straight, L and U shapes are connected open paths. A rectangle links opposite lengths and shares its final endpoint with its start. Custom connected paths use right-angle directions; crossing, retracing and unintended contact between runs are rejected. Separate fences retain separate endpoints, even if the schematic rows align.

Each solid span between an endpoint and a gate support is divided into equal bays. A corner that joins consecutive runs is counted once. Gate supports take priority when a shared endpoint is also a gate support. This is an orthogonal schematic, not a survey, terrain model or map measurement.

Bays in a solid span = ceil(span length ÷ maximum post spacing)
Bay center distance = span length ÷ bays

2. Clear gate width is not post-center span

For two equal square gate posts of entered actual width p inches, a clear opening g feet needs a support-center span of g + p/12 feet. This adds half of each gate-post width. If you already have a post-center specification, choose center-span mode so no width is added. The gate start measures to the first gate-post center along the run.

Support span (ft) = clear opening (ft) + gate-post width (in) ÷ 12
Solid spans = [run start, first gate support] and [second gate support, run end]

The tool currently supports one gate per run, a uniform entered gate-post width, and a complete gate-kit allowance for each opening. A double gate is one opening; its kit price must cover both leaves and all required gate hardware. Gate leaves and framing are excluded from the ordinary board and rail counts.

See the measurement diagrams →

3. Picket coverage and board arrangements

For the default between-post mode, the actual widths of the two supporting posts are subtracted from the center distance. Gate and ordinary supports can have different widths.

Clear bay width (in) = bay center distance × 12 − (start-post width + end-post width) ÷ 2
Side-by-side boards = max(1, ceil((coverage width + gap) ÷ (board width + gap)))

This model begins and ends with a board and may require trimming the last board or adjusting the final gap. Centerline allowance mode instead uses the full center distance. It is a quantity allowance, not an exact face-mounted cut schedule; it does not add the outside half-widths of endpoint posts.

The board-on-board mode is a specific geometric model: equal-width boards alternate between back and front layers, with the same overlap between each adjacent pair. The first board starts at the bay edge. Overlap must be greater than zero and no more than half the board width. Different manufacturer layouts can require a different count.

Alternating board-on-board count = max(1, ceil((coverage width − adjacent overlap) ÷ (board width − adjacent overlap)))
Purchase boards = ceil(sum of base boards × (1 + extra lumber % ÷ 100))

This formula is derived from the interval coverage w + (n − 1)(w − overlap), not copied from a product installation schedule. It does not calculate shadowbox, horizontal boards, vinyl kits or chain link. The tool does not claim that all board-on-board systems use this arrangement.

4. Rail stock, cuts and fastener packs

Rails are modeled between post faces. Each bay receives the entered number of rows. Each rail uses one full stock piece, even if an offcut could serve another bay. The selected stock length must cover each clear-width cut. Spare rail stock is added after calculating installed rails. The report groups approximate cut lengths; field measurements and connector details determine final cuts.

Base rails = bays × rows per bay
Purchase rail stock = ceil(base rails × (1 + extra lumber % ÷ 100))
Picket fasteners = base boards × rail rows × entered fasteners per connection
Rail fasteners = base rails × 2 ends × entered fasteners per end
Boxes = ceil(required fasteners ÷ entered pieces per box)

Picket and rail boxes are separate purchase lines because the required fastener sizes may differ. These are editable count assumptions, not a nail or screw design. Spare boards do not add installation fasteners. Optional post caps are counted one per support but must match the respective ordinary and gate-post sizes.

5. Concrete, gravel and post stock

Ordinary supports and gate supports use separate square-post and cylindrical-hole dimensions. The post sits on top of any gravel base in this model; concrete fill depth excludes gravel and any unfilled top. Post stock length must cover the entered above-grade post height plus concrete fill and any unfilled top depth. Total excavation is concrete fill + gravel base + unfilled top. Post embedment is concrete fill + unfilled top because the post sits above the gravel. This geometric check does not establish adequate embedment or structural strength.

Net cu ft per hole = (π × (hole diameter ÷ 2)² − square post width²) × concrete fill depth ÷ 1728
Adjusted group volume = net cu ft per hole × group post count × (1 + concrete allowance % ÷ 100)
Pooled bags = ceil(sum of adjusted volumes ÷ product yield)
Per-hole bags = sum over groups: post count × ceil(adjusted per-hole volume ÷ product yield)

The purchase list follows the selected rounding mode. Pooled mode assumes unused usable mix can be distributed across holes; per-hole mode rounds every hole separately. Never distribute dry or mixed material contrary to the product instructions. Hole diameter must exceed the square post diagonal.

Optional gravel uses the full cylindrical base area, multiplied by base depth, then rounds total volume to the entered bag volume. The post displacement is not subtracted from the base because the model places the post above it.

The product-specific yield presets are drawn from the cited manufacturer data sheet. They are not universal yields for bags of the same weight. See source details and the discrepancy we did not silently adopt.

6. Prices and A/B comparison

Every price starts blank. Optional, dated Home Depot listing snapshots cover matching cedar pickets and selected post, rail and concrete specifications. Applying one is explicit; it does not overwrite an existing price. Material or size changes clear an applied snapshot. Edited prices are treated as user entries. Snapshots do not provide a complete basket, local availability or a national median. A blank required line makes the complete total unavailable; a user-entered zero is treated as zero. The known-material subtotal is only the sum of priced lines. Material tax applies to those priced material lines; labor is gross run footage times the entered rate, and other budget is a separate entered allowance.

Complete total = sum(purchase quantity × entered unit price) + material tax + entered labor + other budget

Option B uses the same layout, gate dimensions, mounting method, post/footing sizes, bag product and rail rows. Its spacing, board width, gap/overlap, arrangement, extra lumber and quote can differ. Neither a lower cost nor equal totals proves that the two products have equivalent quality or structural suitability. Quote dates and references are user-entered and are not authenticated.

7. Important exclusions

No automatic property survey, slope correction, frost-depth lookup, soil analysis, wind-load design, pool-barrier check or local legal interpretation is performed. Surveying, permit fees, removal, rental, delivery, stain, structural gate reinforcement and specialty connectors need separate checks and pricing. Published starting dimensions and fastener counts are examples, not recommendations.

Check two complete worked examples · Review sources and validation limits · Open the planner

Editable sketch and units

The sketch edits a temporary right-angle layout using the same calculation engine. Applying replaces the detailed layout; cancelling leaves it unchanged. A new shape starts with evenly divided example lengths and retains existing gates where possible. Verify measurements before confirming. Rectangles link opposite sides. The sketch does not infer property lines, terrain or structural suitability.

Feet and inches convert to decimal feet as feet + inches / 12. Feet components must be whole nonnegative numbers; inches must be below 12. Drawn side dimensions are between post centers, and gate placement preserves the project’s clear-opening or post-center measurement mode.

Simple estimate: wood and vinyl

The simple form keeps its own inputs. “Bring in this project” explicitly copies a valid wood configuration into the detailed planner, replacing that detailed plan. Vinyl is never silently converted to wood. “Start from default sample” opens a separate 140 ft U-shape example; “Keep working on detailed plan” preserves prior detailed edits. It models a straight fence divided into max(1, gate count) equal sections, with one centered gate per section. Gate support spans include the entered clear width plus one full gate-post width. No corners, slopes or offcut reuse are modeled.

Wood uses the detailed engine with 5.5-inch pickets, no gap, your entered maximum post spacing (8 ft initially), three rails per bay and 10% extra boards and rails. Selecting cedar changes the material label, not the geometric formula. The chosen height identifies stock; it does not certify spacing, embedment or wind resistance.

Vinyl counts ceil(solid post-center span / entered maximum system span) complete panel kits for each side of each gate. Total posts equal panel bays plus gates plus one for this connected straight layout. Confirm that the manufacturer permits trimmed bays. Internal pickets and rails are not separately purchased in this model. Concrete remains unpriced and uncounted unless you enter a product-specific per-post bag allowance; total bags = ceil(posts × allowance). This does not validate hollow-post reinforcement or foundations.

Optional cost range = gross length × your low/high per-foot materials allowance + gates × your low/high complete gate-kit price. Include posts, infill, concrete and fasteners in your per-foot allowance, and exclude gates to avoid double counting. Missing quotes prevent a range. Tax, labor and delivery are excluded. References: Barrette product-specific instructions and Home Depot vinyl installation guidance. These references support using product-specific installation dimensions, not a universal kit specification.

Beginner and Full modes

Beginner mode shows layout plus material, picket height, picket width, gap, maximum post spacing and rails per bay. Other settings retain their current values, summarized in the results and report. Full mode exposes every setting without resetting inputs. Three rails are a fixed planning allowance in the simple estimator, at 4, 6 and 8 ft alike; the height selector does not certify a structural configuration or rail elevation.

Itemized materials budget scenario

The simple estimator lets you enter a unit price for every required line in its current wood purchase list. The complete materials low value is the sum of quantity × unit price; the high value adds your optional cost contingency (0–50%, initially 15%). The same contingency is retained when you explicitly import the itemized quote into the detailed planner.

This is cost uncertainty, not an additional quantity waste factor: boards and rails already include their selected lumber allowance, and concrete already includes its own allowance and bag rounding. Unknown prices remain missing. The range is not a market forecast or confidence interval. Tax, delivery, labor, permits, removal and tools are outside this materials-only scenario. The separate per-foot quote range is an alternative calculation, never added on top.

Complete gate kits must cover leaves, frames and required hardware; a hinge/latch price alone cannot fill that line. A reference stock length must exactly match the selected purchase length. No supplier basket is claimed complete merely because some snapshots are available.

Reference-price starter and beginner settings

Fill matching reference prices is optional. It proposes dated product snapshots only for blank purchase lines and exact supported dimensions; it never replaces an existing quote or changes a stock length to make a product match. Priced-line counts describe the number of required material lines with entered prices, not budget coverage by dollars. Complete material ranges still require every positive-quantity line to be priced.

Beginner mode changes which inputs are visible. It keeps the current detailed settings, which can be reviewed in the nearby settings summary and edited in Full mode. These are planning assumptions, not manufacturer-approved or locally approved defaults. Enter the next missing price opens the full quote section and focuses the required field.