Londonderry Township has 1,975 homes, and half of them were standing by 1978. 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 34 Pa. Code § 403.1(b)(8), alterations to a house that make no structural change are outside the state code. So the township code office in Londonderry Township is the one to ask before work starts.
Source: 34 Pa. Code § 403.1(b)
Layers
On a roof that already carries two layers, or slate or tile, the code allows no recover: it is a tear-off (IRC R908.3.1.1). 54% of Londonderry Township’s homes were built before 1980, so count the layers before comparing quotes.
Ice barrier
The code requires an ice barrier where the local climate table (Table R301.2) says so, and each Pennsylvania municipality fills that table in. The contractor or the township code office in Londonderry Township will know.
Rules as read on October 24, 2026. Code edition, permit and contract rules for the whole state: roof replacement in Pennsylvania.
Of 1,864 occupied homes in Londonderry Township, 1,711 (92%) are owner-occupied. By year built, 6% before 1940, 22% before 1960, 54% before 1980; 10% went up in 2000 or later. (ACS 2020–2024.)
By building type: 82% detached houses, 15% manufactured homes.
Of the 31 Dauphin County municipalities on this site, Londonderry Township has the 20th largest share of homes built before 1980: 54%, against a county range of 31% to 100%.
ZIP codes: 17057
| Place | Median built | Before 1980 | Owners | Row, twin | Hail days |
|---|---|---|---|---|---|
| Londonderry Township, Dauphin County | 1978 | 54% | 92% | 2% | 19 |
| Middletown Borough | 1958 | 78% | 43% | 21% | 20 |
| Lower Swatara | 1983 | 46% | 87% | 14% | 20 |
| Conewago Township, Dauphin County | 1978 | 54% | 89% | 6% | 18 |
| Highspire | 1964 | 75% | 39% | 25% | 19 |
| West Donegal | 1992 | 36% | 69% | 14% | 15 |
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.
Since 2006 the National Weather Service has logged hail of 1 inch or larger on 19 separate days within 10 miles of Londonderry Township; the largest was 2 in on May 14, 2010. The most recent was September 21, 2024.
That is more hail days than 89% of the places in the state on this site.
Federal major-disaster declarations for storms in Dauphin County since 2006: 5, most recently DR-4618, Remnants of Hurricane Ida, declared September 2021. (OpenFEMA.)
A report says hail fell near Londonderry Township, 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 Londonderry Township’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; 82% 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 | Simple roofs with long, unbroken slopes | Standing seam that carries its own loads can skip the tear-off (R908.3.1) |
| Slate | 75 years | Older houses; 6% here predate 1940 | Sound slate can be reused (R908.5); broken slate cannot |
| Flat roof: EPDM or TPO | 15 years | Porches, additions, low-slope rears | Coating is not a replacement |
Before signing for a roof in Londonderry Township, get the contractor’s PA registration number: the home improvement law requires registration with the Attorney General above $5,000 a year of such work, and the number on contracts and estimates (HICPA § 3, § 6).
The price side is in what a new roof costs in Pennsylvania; the paperwork side in checking a roofing contractor.
Ask Londonderry Township first. Under 34 Pa. Code § 403.1(b)(8), alterations to a house that make no structural change are outside the state code. So the township code office in Londonderry Township is the one to ask before work starts.
On a roof that already carries two layers, or slate or tile, the code allows no recover: it is a tear-off (IRC R908.3.1.1). 54% of Londonderry Township’s homes were built before 1980, so count the layers before comparing quotes.
By the Census Bureau’s American Community Survey (2020–2024), the median home in Londonderry Township was built in 1978, 54% of homes were built before 1980, 92% are owner-occupied.
Hail of 1 inch or larger was reported on 19 days within 10 miles of Londonderry Township from 2006 through 2025 (NOAA Storm Prediction Center). A report means hail fell nearby, not that a roof was damaged.
Before signing for a roof in Londonderry Township, get the contractor’s PA registration number: the home improvement law requires registration with the Attorney General above $5,000 a year of such work, and the number on contracts and estimates (HICPA § 3, § 6).
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.