Hackettstown has 3,875 homes, and half of them were standing by 1967. The rules below decide how much of the old roof has to come off and what goes under the new one.
New Roofing Costs connects homeowners with independent local roofing contractors. We do not perform roofing work.
This number connects homeowners who are planning a new roof or a full roof replacement with independent local roofing contractors. It is not for leak repairs or patch jobs. The call must come from the homeowner who decides on the roof. Calls may be recorded.
Permit
New Jersey treats a new covering on a detached one- or two-family house as ordinary maintenance: no permit, no notice (N.J.A.C. 5:23-2.7). That covers the 55% of Hackettstown’s homes that are detached; twins, rowhouses, townhouses and structural work are outside it.
Source: N.J.A.C. 5:23-2.7
Layers
The state strikes the IRC reroof definitions from its code (N.J.A.C. 5:23-3.21) and leaves existing houses to the Rehabilitation Subcode, not yet checked here. 68% of Hackettstown’s homes were built before 1980: ask how many layers yours has and whether the price is for a tear-off to the deck.
Source: N.J.A.C. 5:23-3.21
Ice barrier
New Jersey requires the eave membrane only where January averages 25 °F or colder, which the state says is Sussex County (DCA Bulletin 07-3). Hackettstown is outside it, so whether to add one is up to you and the installer.
Source: N.J.A.C. 5:23-3.21; NJ DCA Bulletin 07-3
Rules as read on October 24, 2026. Everything else the state requires: roof replacement in New Jersey.
Of 3,841 occupied homes in Hackettstown, 2,220 (58%) are owner-occupied. By year built, 23% before 1940, 36% before 1960, 68% before 1980; 16% went up in 2000 or later. (ACS 2020–2024.)
By building type: 55% detached houses, 7% attached single-family houses (rowhouses, twins and townhouses), 13% buildings of two to four units.
Of the 22 Warren County municipalities on this site, Hackettstown has the 7th largest share of homes built before 1980: 68%, against a county range of 24% to 89%.
| Place | Median built | Before 1980 | Owners | Row, twin | Hail days |
|---|---|---|---|---|---|
| Hackettstown | 1967 | 68% | 58% | 7% | 7 |
| Independence | 1986 | 39% | 83% | 29% | 6 |
| Mount Olive | 1978 | 54% | 61% | 4% | 11 |
| Allamuchy | 1983 | 45% | 83% | 44% | 7 |
| Washington Township, Morris County | 1979 | 52% | 91% | 5% | 5 |
| Mansfield Township, Warren County | 1981 | 48% | 62% | 6% | 5 |
Median built: median year the homes were built. Before 1980: share of homes built then. Owners: share of homes that are owner-occupied. Row, twin: share of homes that are rowhouses, twins or townhouses. Census ACS 2020–2024. Hail days: days with hail of 1 inch or larger within 10 miles, 2006–2025, NOAA Storm Prediction Center.
NOAA’s storm reports show 7 days since 2006 with hail of at least 1 inch inside a 10-mile circle around Hackettstown, topping out at 1.25 in on September 8, 2023.
That is fewer than most places in the state on this site (median 11 days).
Federal major-disaster declarations for storms in Warren County since 2006: 10, most recently DR-4725, Severe Storm and Flooding, declared August 2023. (OpenFEMA.)
A report says hail fell near Hackettstown, not that it damaged a roof. When wind or hail damage means a new roof.
HUD’s useful-life figures are for planning; a warranty is a separate promise. For Hackettstown’s houses: More in the guides to shingles, metal, slate and flat roofs.
| Material | HUD useful life | Fits a house like | Watch for |
|---|---|---|---|
| Asphalt shingles | 20 years | Most pitched roofs; 55% of homes here are detached | Wind class set by the design wind speed (IRC Table R905.2.4.1) |
| Metal (standing seam, panels) | 50 years | Low pitches and long runs | Standing seam that carries its own loads can skip the tear-off (R908.3.1) |
| Slate | 75 years | Older houses; 23% here predate 1940 | Never a base for a new layer (R908.3.1.1); heavy |
| Flat roof: EPDM or TPO | 15 years | Porches, additions, low-slope rears | Where the roof meets a wall or parapet |
New Jersey had 47,473 active home improvement registrations in October 2026; the one belonging to whoever quotes your roof in Hackettstown should be on the contract (N.J.S.A. 56:8-144).
The price side is in what a new roof costs in New Jersey; the paperwork side in checking a roofing contractor.
None for a detached one- or two-family house. New Jersey treats a new covering on a detached one- or two-family house as ordinary maintenance: no permit, no notice (N.J.A.C. 5:23-2.7). That covers the 55% of Hackettstown’s homes that are detached; twins, rowhouses, townhouses and structural work are outside it.
By the Census Bureau’s American Community Survey (2020–2024), the median home in Hackettstown was built in 1967, 68% of homes were built before 1980, 58% are owner-occupied.
Hail of 1 inch or larger was reported on 7 days within 10 miles of Hackettstown from 2006 through 2025 (NOAA Storm Prediction Center). A report means hail fell nearby, not that a roof was damaged.
New Jersey had 47,473 active home improvement registrations in October 2026; the one belonging to whoever quotes your roof in Hackettstown should be on the contract (N.J.S.A. 56:8-144).
The full list: before you call.
Checked October 24, 2026. Laws and code editions change; the date says when these were last read at the source.