Fences in New Hampshire go into some of the hardest ground in New England. Southern-tier yards in Salem, Windham and Hudson are glacial till full of cobbles. Ledge sits a foot or two down across much of the state. And every winter the ground freezes, then thaws into the mud season that runs through March and April. A fence that looks perfect in August can lean by the following May if the posts were set wrong.
Fence permits and setbacks: start at the town office
New Hampshire does not license fence installers; the rules that matter are local. Some towns require a permit for a fence, especially one over a set height, and many have setback rules from a property line or the road, or limits on height in a front yard. Manchester gets the question often enough that "Do I need a permit for a fence?" is one of the standard questions on its Building FAQ.
In smaller towns such as Hampstead, Atkinson, Kingston or Litchfield, the answer may come from the zoning ordinance rather than a building inspector. Before you sign a contract:
- Call the town's building or land-use office and ask whether a fence permit is needed, what height is allowed in front and back yards, and whether there is a setback from the property line.
- Check any homeowner association covenants. Subdivisions in Bedford and Londonderry often restrict fence style, height or color.
- If you are on a corner lot, ask about sight lines at the intersection. Many towns limit fence height near the corner so drivers can see.
Write into the contract who obtains the permit, if one is required.
Marking the fence line in white and calling 811
State law counts a post hole as digging like any other. RSA 374:51 makes the person excavating give the utilities three business days of warning through the one-call center, so a weekend or a holiday in between pushes the start back, and the call can be made at most a month ahead. Before calling, the digger outlines the fence line in white, with paint, flags or stakes.
So a fence crew that wants to dig on a Monday should have called in the ticket by the Wednesday before. The request goes in by dialing 811, and it costs nothing. Utilities then come out and mark their lines with colored paint or flags.
Usually the fence contractor calls in the ticket. Confirm that in the contract, and ask to see the ticket number. Utility marks show the public lines, not your private ones: a buried line to a detached garage, an invisible dog fence, irrigation, a propane line to a generator or the pipe to your septic tank are yours to locate. Tell the crew where you know them to be.
Frost heave: post depth and footings
Frost moves fence posts. When wet soil freezes, it expands and grabs the post, lifting it a little each winter. Posts that are too shallow, or set in concrete shaped like a mushroom at the top, ride up and lean.
Ask each contractor how deep they set posts and why. The answer should depend on the fence height, the soil and how far frost goes in your part of the state, which is deeper in Lancaster or Whitefield than in Nashua. Ask whether they set posts in concrete, gravel or a mix, and whether the hole is wider at the bottom than the top. Ask how they set gate posts, which carry the most load and fail first.
Ledge and stone: when the auger hits granite
Much of New Hampshire sits on granite, and ledge near the surface is common from Pelham to Rochester. When an auger hits rock, the crew has to move the post, drill into the ledge and pin the post, or set it in a surface footing.
A good quote says what happens when the crew hits ledge or a large boulder, and what each fix costs. Some contractors include a few rock holes in the price; others charge each one extra. Ask, and get the answer in writing, or a $4,500 fence can become a $6,000 one on the first day.
Boundary lines, surveys and the fence that ends up on a neighbor's land
The most expensive fence mistake has nothing to do with posts. A fence built a foot over the line belongs, in effect, to the neighbor, and moving it costs as much as building it. Stone walls, old fences and hedges in rural New Hampshire towns often do not follow the deeded line.
If you are not sure where the line is, a survey with set corner pins is cheap insurance on a long fence. Ask the fence contractor to set the line off the survey pins, a few inches inside your side, and talk to the neighbor before work starts. A fence contractor is not a surveyor and should not be guessing where your property ends.
A fence that doubles as a pool barrier
If the fence will enclose a swimming pool, it stops being only a matter of looks. New Hampshire's state building code adopts the 2024 International Swimming Pool and Spa Code, and pool barriers have specific rules on height, gaps, gates that close and latch on their own, and how close climbable objects may sit to the fence. Your town may check the barrier as part of the pool permit.
Tell the fence contractor at the first visit that the fence is a pool barrier. Ask whether they have built barriers that passed inspection in your town, which gate hardware they use, and whether the style you like, such as a split rail or a horizontal board fence, can meet the rules at all. Some cannot, because the rails make a ladder for a small child. Getting this wrong means rebuilding the gate or a run of fence before the pool can be used, and a summer lost in a state where the swimming season is short already.
Pricing 150 feet of wood privacy fence
A 150-foot wood privacy fence runs about $3,550 to $7,000 in the New Hampshire fence cost estimate. Material changes the number most: vinyl and aluminum cost more up front and need little upkeep, cedar and pressure-treated pine cost less and need stain or paint, and chain link is cheapest. Gates, removal of an old fence and hauling it away, slopes that need stepped panels, and rock all add to the bill.
Compare quotes on the same items: total linear feet, height, material and style, post size and depth, number and width of gates, removal and disposal, and the warranty on materials and labor. With no state contract law for this work, a deposit is whatever you agree to, so tie it to the material order. If a company takes a deposit and never shows, the Consumer Protection Act's ban on unfair and deceptive dealing is the basis for a complaint to the Attorney General or a claim of your own (RSA 358-A:2).
