Half of the 4,348 homes in Mount Joy Township were built before 1991. What the code requires when that roof is replaced, and who signs off, is below.
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
Pennsylvania’s code leaves residential alterations without structural change to local ordinance (34 Pa. Code § 403.1(b)(8)). The township code office can say what Mount Joy Township requires.
Source: 34 Pa. Code § 403.1(b)
Layers
A new roof may go over one existing layer; with two or more, or over slate, clay or cement tile, everything comes off to the deck (IRC R908.3.1.1). With 34% of Mount Joy Township’s homes were built before 1980, ask what is under the newest layer.
Ice barrier
IRC R905.1.2 calls for an ice barrier where Table R301.2 says so; in Pennsylvania the municipality completes that table. Ask the township code office or the contractor what Mount Joy Township’s says.
Rules as read on October 24, 2026. Everything else the state requires: roof replacement in Pennsylvania.
Owners live in 3,106 of Mount Joy Township’s occupied homes, or 73%. By year built, 7% before 1940, 17% before 1960, 34% before 1980; 33% went up in 2000 or later. (ACS 2020–2024.)
By building type: 57% detached houses, 16% attached single-family houses (rowhouses, twins and townhouses), 6% buildings of two to four units, 8% manufactured homes.
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 59 Lancaster County municipalities on this site, Mount Joy Township has the 55th largest share of homes built before 1980: 34%, against a county range of 27% to 87%.
ZIP codes: 17022 · 17552
| Place | Median built | Before 1980 | Owners | Row, twin | Hail days |
|---|---|---|---|---|---|
| Mount Joy Township, Lancaster County | 1991 | 34% | 73% | 16% | 19 |
| Elizabethtown | 1964 | 70% | 58% | 21% | 17 |
| Mount Joy Borough | 1974 | 57% | 63% | 21% | 17 |
| West Donegal | 1992 | 36% | 69% | 14% | 15 |
| Rapho | 1988 | 38% | 80% | 15% | 17 |
| Conewago Township, Dauphin County | 1978 | 54% | 89% | 6% | 18 |
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 19 days since 2006 with hail of at least 1 inch inside a 10-mile circle around Mount Joy Township, topping out at 1.75 in on March 29, 2009. The most recent was June 28, 2025.
That is more hail days than 89% of the places in the state on this site.
Federal major-disaster declarations for storms in Lancaster County since 2006: 3, most recently DR-4267, Severe Winter Storm and Snowstorm, declared March 2016. (OpenFEMA.)
A report says hail fell near Mount Joy Township, not that it damaged a roof. When wind or hail damage means a new roof.
Useful life is HUD’s planning figure, not a warranty. 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; 57% 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 | Roofs that will carry solar later | Standing seam that carries its own loads can skip the tear-off (R908.3.1) |
| Slate | 75 years | Older houses; 7% 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 (16% of homes here are attached) | Seams at walls and drainage |
Pennsylvania’s home improvement law (HICPA § 3, § 6) requires registration with the Attorney General from $5,000 a year of such work and puts the number on every estimate; ask for it in Mount Joy Township and look it up.
The price side is in what a new roof costs in Pennsylvania; the paperwork side in checking a roofing contractor.
Ask Mount Joy Township first. Pennsylvania’s code leaves residential alterations without structural change to local ordinance (34 Pa. Code § 403.1(b)(8)). The township code office can say what Mount Joy Township requires.
A new roof may go over one existing layer; with two or more, or over slate, clay or cement tile, everything comes off to the deck (IRC R908.3.1.1). With 34% of Mount Joy Township’s homes were built before 1980, ask what is under the newest layer.
By the Census Bureau’s American Community Survey (2020–2024), the median home in Mount Joy Township was built in 1991, 34% of homes were built before 1980, 73% are owner-occupied.
Hail of 1 inch or larger was reported on 19 days within 10 miles of Mount Joy Township from 2006 through 2025 (NOAA Storm Prediction Center). A report means hail fell nearby, not that a roof was damaged.
Pennsylvania’s home improvement law (HICPA § 3, § 6) requires registration with the Attorney General from $5,000 a year of such work and puts the number on every estimate; ask for it in Mount Joy Township and look it up.
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.