How to Estimate Fence Installation Jobs: Posts, Slope, Gates

Short answer: How to estimate fence installation jobs means pricing per linear foot but building the number from post count. Divide each run by your post spacing, round up, add one post per run and two more per gate. Price the holes next: a 12-inch by 36-inch hole with a 4x4 in it takes about 2.1 cubic feet of concrete, near five 60-pound bags. Slope handling, utility locates, dig conditions, demolition, and every gate sit outside the per-foot rate.

A fence is sold by the foot and built by the hole. The customer hears one number, and the money is decided by how many holes you dig, how hard the ground is, how far the yard falls, and how many gates you agreed to before you thought about the hardware. This walk takes about thirty minutes on a typical back yard and saves the day you would otherwise spend rebuilding a run you priced flat.

What do I settle before I unroll the tape?

Where the line actually goes. Not where the customer waves, and not the edge of the mowed grass.

Ask for the plat or survey and look for the pins at the corners. If nobody can find a pin, that is a conversation to have now, in writing, because a fence set on the wrong side of a line comes out at your expense and no per-foot price covers that. Then check setbacks, height limits, and whether the good side has to face out — those come from the municipality and often from an HOA on top of it, and both can force a design change after you have already quoted.

Walk to the neighbor’s side too. A shared line, a fence you have to tie into, or a hedge grown over the property line all change the labor before they change anything else.

How do I measure the fence line so the post count is right?

Wheel each straight run separately and write it down as its own run. Do not add them into one total, because posts are counted per run and the rounding matters.

For each run: length divided by your post spacing, rounded up, gives the number of bays. Posts are bays plus one. Then add two posts for every gate, because a gate needs a dedicated post on each side and those posts are heavier, deeper, and set in more concrete than a line post.

Run	Length	Spacing	Bays	Posts
A, along the back	104 ft	8 ft	13	14
B, down the side	74 ft	8 ft	10 at 7.4 ft	11
Walk gate, 4 ft	—	—	—	+2
Drive gate, 10 ft	—	—	—	+2
Total	178 ft		23	29

That is the whole reason a per-foot price is dangerous on its own. Run B at 74 feet does not divide evenly by 8, so it goes to ten bays at 7.4 feet — one more hole, one more bag of concrete, one more set-and-plumb than the foot count implies.

The rest of the material falls out of the bay count. On a 6-foot wood privacy fence with three rails, each 8-foot bay takes 24 linear feet of 2x4. Dog-ear pickets at 5.5 inches wide with no gap run about 2.18 pickets per foot, so 178 feet needs roughly 388 pickets before waste.

How much concrete does each hole actually take?

Volume of the hole minus volume of the post. Hole volume is pi times the radius squared times the depth, all in feet.

A 12-inch hole 36 inches deep is 2.36 cubic feet. A 4x4 post occupies 0.26 of that over the same depth, leaving 2.10 cubic feet of concrete — about 4.7 bags of 60-pound mix at 0.45 cubic feet per bag, or 3.5 bags of 80-pound. A 6x6 gate post in a 12-inch hole 42 inches deep takes closer to 2.0 cubic feet after the post displaces its share, and gate posts usually go deeper still.

Depth is set by two things: at least a third of the post’s above-ground height, and below the local frost line. The frost depth comes from the building department, not from a rule of thumb, and in a cold market it is often the number that drives the whole dig cost. Twenty-nine holes at 36 inches versus 29 holes at 48 inches is a different day with a different auger.

What does the slope do, and does the fence step or rack?

This is the line item that separates people who have installed fences from people who have quoted them.

Material	How it handles grade	What it does to labor
Stick-built wood, rails cut on site	Racks — rails follow the grade, pickets stay plumb	Slowest per bay, no gaps at the bottom, most cutting
Preassembled wood or vinyl panels	Steps — each bay sits level, leaving a triangular gap	Fastest per bay, gaps at the bottom the customer will notice
Vinyl privacy systems	Steps in most systems; some racked kits exist	Post heights change per bay, so measure elevation at every post
Chain link	Follows grade naturally	Least affected, but terminal posts still have to be plumb
Aluminum ornamental	Racks only within the panel’s rated angle	Beyond the rating, panels have to be stepped or cut

Measure the fall, do not eyeball it. Run a string line level from the high corner and measure down to grade at each post location, or use a level and tape bay by bay. Write the drop per bay on the sketch. Three feet of fall across a 104-foot run is a shrug; three feet of fall across 24 feet is a stepped section, extra post length, and a retaining conversation.

What do I need to know about the dig?

Everything, and you can only find out part of it standing there.

Utility locates come first. Calling 811 before digging is free and is required across the country, and OSHA’s excavation rule at 1926.651(b) requires that the estimated location of underground installations be determined before an excavation is opened and that facility owners be contacted. Mark your proposed line in white before they come out, so the locators mark the strip you are actually digging.

Mark color	What is under it
White	Your proposed excavation — you paint this
Pink	Temporary survey markings
Red	Electric power, cables, conduit
Yellow	Gas, oil, steam, other flammables
Orange	Communications, alarm, signal
Blue	Potable water
Purple	Reclaimed water, irrigation
Green	Sewer and drain

Public locates stop at the meter. The gas line to the fire pit, the low-voltage lighting, the sprinkler mains, the invisible dog fence, and the feed to the detached garage are private and nobody is coming to mark them. Say so on the estimate and say who is responsible.

Then the ground itself. Probe a few likely holes with a bar. Rock, hardpan, clay, tree roots, old footings, and buried construction debris each turn a two-minute auger hole into a twenty-minute hand dig, and a run along a wooded line will hit roots on most of its holes. Price the dig as a stated condition with a per-hole adder for refusal, rather than absorbing it.

What do I photograph on a fence walk?

Each run end to end, standing at both ends. The corners and any pin you found. The grade change, shot from the side so the fall is visible. Existing fence to be removed, including the condition of the posts and whether they are set in concrete. Every obstruction along the line: AC units, meters, window wells, tree trunks, retaining walls, sheds. The gate locations with something for scale. The access route from the truck to the back yard, including the gate width you have to get a machine through — a 34-inch side gate rules out most augers and turns the dig into hand work.

What do I ask the customer while I am standing in the yard?

• Which side faces out, and has anyone told you what the HOA or the city requires?
• Is the old fence mine to remove, and do the old posts and footings leave the property?
• Where do you want the gates, how wide, and which way should they swing?
• Do you want a drive gate wide enough for a mower, a trailer, or a truck? Those are three different widths.
• Do you know where the sprinkler lines and the low-voltage wiring run?
• Dogs? A dog that digs changes the bottom detail, and a dog on site changes the schedule.
• Has the neighbor been told, and is any of this cost shared?
• Is there a deadline — a pool inspection, a closing, a puppy arriving?

The gate questions are the ones people skip. A 10-foot double drive gate is not two walk gates; it is heavier posts, a drop rod, a different hinge class, and a frame that has to stay square for years.

How do the counts turn into a price?

Cost one bay and one hole, then multiply, then add everything that is not per-foot.

Line	Quantity	Note
Bays	23	Rails, pickets, fasteners per bay
Line posts	25	Post, hole, concrete, set and plumb
Gate posts	4	Heavier stock, deeper hole, more concrete
Concrete	25 × 4.7 bags + 4 × 5.5 bags = 140 bags	60-pound mix
Demolition	42 lf of old chain link	Pull posts, break footings, haul off
Gates	1 walk, 1 double drive	Hardware priced by unit, not by foot
Slope work	24 ft stepped section	Extra post length, extra cutting
Spoil	29 holes of dirt plus old footings	Haul-off or spread, decide and price it
Crew hours	Layout 1.5, dig and set 9.0, frame and picket 11.0, gates 3.5, cleanup 2.0	27.0 crew-hours

Multiply crew-hours by your own loaded hourly cost — wages, burden, the truck, the auger, and the share of insurance and yard that hour carries. Add delivered material. Add overhead. Then add profit and be precise about which one: markup is a percentage of cost, margin is a percentage of price. Adding 35 percent markup to $5,000 of cost gives $6,750, which is a 26 percent margin. Holding a real 35 percent margin means dividing by 0.65 and quoting $7,692. Then, if you want a per-foot number for the customer, divide the total by 178 — derived, not copied.

Per-foot rates published online move by a factor of two or more depending on material, frost depth, terrain, and local labor. Treat them as a sanity check only; the build-up in how much to charge for fence installation starts from your own bay and hole costs instead.

What gets left out of fence bids?

Demolition and disposal of the old fence, which is heavy and priced by weight at the transfer station. Old concrete footings, which come out as a separate operation and sometimes do not come out at all. Spoil from 29 fresh holes, which has to go somewhere. Gate hardware upgrades — self-closing hinges and latches are mandatory around a pool in most jurisdictions. Post caps, trim boards, and kickboards. Stain or sealer, which is a second visit after the wood dries. Locate delays, when the marks arrive late and you lose a scheduled crew day. Rock clauses. Wire mesh at the bottom for a digging dog. Restoring the strip of lawn you drove the auger over. And the drive time on a route day, which is real cost and deductible if the log holds up, which is what independent contractor mileage log covers.

What do I keep once the fence is up?

The as-built post count against your estimate, the number of holes that hit refusal, and the actual crew-hours per stage. After three jobs your dig rate stops being a guess. Keep the locate ticket number and the photos of the marks — that is your record if something under the yard turns out to be somewhere the marks said it was not.

Keel is an iOS app that keeps that record on the phone: no account, no bank connection, no cloud, no login, and an App Store privacy label reading Data Not Collected. It does not write the estimate — that stays wherever you build it today. What it covers is the part after the yes. The invoice goes out from the yard the afternoon the last gate is hung, with your own numbering, your logo, your brand color, and a payment link the customer scans as a QR code off your screen, which on residential fence work is the difference between paid before you load the auger and chasing a check for six weeks — the same structure as the fence invoice template, and the reason the collection tactics in how to get clients to pay rarely have to come out. Lumber receipts, concrete, hardware, and auger rental get photographed and read on device by Apple Intelligence, and the year exports as a single file. Free covers unlimited invoices, receipts, and mileage; Keel Pro is a one-time $249.99 Lifetime purchase, not a subscription. You can get it on the App Store.

Frequently asked questions

How do I calculate how many posts a fence needs? Take each straight run separately. Divide the run length by your post spacing and round up to get the number of bays, then add one post to close the run. Add two more posts for every gate, since gates need a dedicated post on each side. Rounding up on each run individually is what a single per-foot number hides.

Should I quote fence installation per linear foot or per job? Give the customer a total, built from a per-foot rate you calculated plus separate lines for the things that do not scale with length. Gates, demolition, slope work, rock clauses, and haul-off all sit outside the per-foot number. A run with three gates and 40 feet of stepped grade costs far more per foot than a flat straight line of the same material.

How deep do fence post holes need to be? Deep enough to clear the local frost line and at least a third of the post’s above-ground height, whichever is greater. Your building department publishes the frost depth. In a cold market that number, not the fence height, usually drives the dig cost — moving from 36 to 48 inches on 29 holes adds meaningful concrete, spoil, and labor to the same fence.

Do I have to call 811 before installing a fence? Yes. Contacting the one-call center before digging is free and is required nationwide, and OSHA’s excavation standard requires locating underground installations before opening an excavation. Mark your proposed line in white first. Remember that public locates stop at the meter, so private lines like irrigation, low-voltage lighting, and gas to a fire pit are not marked by anyone.

How does a sloped yard change a fence estimate? It decides whether the fence steps or racks, and that changes both material and labor. Stick-built wood racks and follows grade with more on-site cutting. Preassembled panels and most vinyl systems have to be stepped, which changes post heights bay by bay and leaves gaps at the bottom. Measure the drop at every post rather than estimating it from a photo.

What should a fence estimate exclude? Rock, hardpan, roots, and buried debris in the post holes. Private utility lines that public locates do not mark. Survey work and property line disputes. Removal of old footings. Permits and HOA approvals. Grading, retaining walls, and lawn restoration. Stain or sealer as a return visit. Naming those in writing is what keeps a surprise underground from turning into an argument about the invoice.

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This article is general information, not professional or tax advice.