The median home in Kennett Square was built in 1957; there are 2,340 of them. 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)). Whether Kennett Square wants a permit is in its own ordinance; ask the borough code office before the old roof comes off.
Source: 34 Pa. Code § 403.1(b)
Layers
IRC R908.3.1.1 forbids roofing over two existing layers, over slate or tile, or over a water-soaked roof. With 75% of Kennett Square’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. Kennett Square’s answer is with the borough code office.
Checked against the code text on October 24, 2026. The state’s code edition and the rest of its rules: roof replacement in Pennsylvania.
56% of the occupied homes in Kennett Square are lived in by their owners: 1,244 households, the people this line is for. Counting by decade, 29% before 1940, 56% before 1960, 75% before 1980 of the housing was in place, and 9% dates from 2000 on. (ACS 2020–2024.)
The housing is 53% detached houses, 15% attached single-family houses (rowhouses, twins and townhouses), 11% buildings of two to four units.
Of the 71 Chester County municipalities on this site, Kennett Square has the 2nd largest share of homes built before 1980: 75%, against a county range of 12% to 80%.
| Place | Median built | Before 1980 | Owners | Row, twin | Hail days |
|---|---|---|---|---|---|
| Kennett Square | 1957 | 75% | 56% | 15% | 11 |
| Kennett | 1991 | 38% | 77% | 19% | 10 |
| East Marlborough | 1988 | 34% | 92% | 19% | 15 |
| New Garden | 1994 | 26% | 77% | 7% | 12 |
| Avondale | 1938 | 69% | 62% | 25% | 10 |
| Pennsbury | 1983 | 42% | 81% | 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.
Within 10 miles of Kennett Square, hail of an inch or more was reported on 11 days between 2006 and 2025, the biggest stones 1.75 in on July 25, 2010. The most recent was June 2, 2019.
At the county level, Kennett Square shares Chester County’s record of 5 storm disaster declarations since 2006, the newest DR-4618 (Remnants of Hurricane Ida, September 2021). (OpenFEMA.)
Storm reports are what observers logged, not a measure of damage to any 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 Kennett Square’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; 53% 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 | A complete standing-seam system may go over the old roof (R908.3.1) |
| Slate | 75 years | Older houses; 29% 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 (15% of homes here are attached) | Coating is not a replacement |
A contractor who does $5,000 or more of home improvement work a year must be registered with the Pennsylvania Attorney General, and the number has to be on every contract and estimate (HICPA § 3, § 6). Ask for it before anyone starts on a roof in Kennett Square, and search it.
Contracts, deposits and the right to cancel: checking a roofing contractor. What moves the price: new roof cost in Pennsylvania.
Kennett Square’s ordinance decides. Pennsylvania’s code leaves residential alterations without structural change to local ordinance (34 Pa. Code § 403.1(b)(8)). Whether Kennett Square wants a permit is in its own ordinance; ask the borough code office before the old roof comes off.
IRC R908.3.1.1 forbids roofing over two existing layers, over slate or tile, or over a water-soaked roof. With 75% of Kennett Square’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 Kennett Square was built in 1957, 75% of homes were built before 1980, 56% are owner-occupied.
Hail of 1 inch or larger was reported on 11 days within 10 miles of Kennett Square from 2006 through 2025 (NOAA Storm Prediction Center). A report means hail fell nearby, not that a roof was damaged.
A contractor who does $5,000 or more of home improvement work a year must be registered with the Pennsylvania Attorney General, and the number has to be on every contract and estimate (HICPA § 3, § 6). Ask for it before anyone starts on a roof in Kennett Square, and search it.
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.