Half of the 8,488 homes in Montgomery were built before 1994. 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
Under N.J.A.C. 5:23-2.7 a reroof of a detached one- or two-family house goes ahead without a permit or a notice to the construction office. Attached houses (17% of Montgomery’s homes) and any work that touches the structure fall outside the rule.
Source: N.J.A.C. 5:23-2.7
Layers
New Jersey deletes the IRC’s reroofing definitions (N.J.A.C. 5:23-3.21(c)2.xxii); its layer rule for existing houses is in the Rehabilitation Subcode, which this site has not read yet. 21% of Montgomery’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
Only Sussex County meets New Jersey’s 25 °F January test for a required ice barrier (N.J.A.C. 5:23-3.21; DCA Bulletin 07-3). For Montgomery, ask whether the quote includes one anyway.
Source: N.J.A.C. 5:23-3.21; NJ DCA Bulletin 07-3
Rules as read on October 24, 2026. Code edition, permit and contract rules for the whole state: roof replacement in New Jersey.
Owners live in 7,163 of Montgomery’s occupied homes, or 85%. By year built, 5% before 1940, 8% before 1960, 21% before 1980; 33% went up in 2000 or later. (ACS 2020–2024.)
By building type: 71% detached houses, 17% attached single-family houses (rowhouses, twins and townhouses).
33% of homes here were built in 2000 or later. HUD’s useful-life table gives an asphalt-shingle roof 20 years, so roofs on houses from the early 2000s are reaching that age.
Of the 18 Somerset County municipalities on this site, Montgomery has the 17th largest share of homes built before 1980: 21%, against a county range of 19% to 87%.
ZIP codes: 08502 · 08558
| Place | Median built | Before 1980 | Owners | Row, twin | Hail days |
|---|---|---|---|---|---|
| Montgomery | 1994 | 21% | 85% | 17% | 8 |
| Princeton | 1965 | 64% | 55% | 16% | 10 |
| Hillsborough | 1986 | 34% | 80% | 20% | 7 |
| Hopewell Borough | 1938 | 79% | 76% | 7% | 11 |
| Franklin Township, Somerset County | 1986 | 36% | 69% | 20% | 8 |
| East Amwell | 1971 | 74% | 83% | 4% | 10 |
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 8 days since 2006 with hail of at least 1 inch inside a 10-mile circle around Montgomery, topping out at 1.75 in on July 23, 2008. The most recent was February 21, 2023.
That is fewer than most places in the state on this site (median 11 days).
Remnants of Hurricane Ida (DR-4614, September 2021) is the latest of 9 federal storm declarations covering Somerset County since 2006. (OpenFEMA.)
A report says hail fell near Montgomery, 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 Montgomery’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; 71% 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; 5% here predate 1940 | Sound slate can be reused (R908.5); broken slate cannot |
| Flat roof: EPDM or TPO | 15 years | Low-slope roofs and rear sections (17% of homes here are attached) | Seams at walls and drainage |
Any business offering home improvements in Montgomery must be registered with the New Jersey Division of Consumer Affairs, with the number on its contracts and ads (N.J.S.A. 56:8-138, 56:8-144); 47,473 registrations were active in October 2026.
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. Under N.J.A.C. 5:23-2.7 a reroof of a detached one- or two-family house goes ahead without a permit or a notice to the construction office. Attached houses (17% of Montgomery’s homes) and any work that touches the structure fall outside the rule.
By the Census Bureau’s American Community Survey (2020–2024), the median home in Montgomery was built in 1994, 21% of homes were built before 1980, 85% are owner-occupied.
Hail of 1 inch or larger was reported on 8 days within 10 miles of Montgomery from 2006 through 2025 (NOAA Storm Prediction Center). A report means hail fell nearby, not that a roof was damaged.
Any business offering home improvements in Montgomery must be registered with the New Jersey Division of Consumer Affairs, with the number on its contracts and ads (N.J.S.A. 56:8-138, 56:8-144); 47,473 registrations were active in October 2026.
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.