Permit
Ask Downingtown first
Under 34 Pa. Code § 403.1(b)(8), alterations to a house that make no structural change are outside the state code. The borough code office can say what Downingtown requires.
Source: 34 Pa. Code § 403.1(b)
Roof Replacement in Downingtown, PA
Downingtown has 3,697 homes, and half of them were standing by 1968. Below: what the code asks of a replacement here, the permit, and the town’s own records.
New Roofing Costs connects homeowners with independent local roofing contractors. We do not perform roofing work.
Call (833) 781-1806 Replacement and new roofs only · homeowners
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.
The rules for a reroof in Downingtown
Layers
One old layer can stay; two cannot
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). 67% of Downingtown’s homes were built before 1980; many have been reroofed before.
Ice barrier
Downingtown’s climate table decides
The code requires an ice barrier where the local climate table (Table R301.2) says so, and each Pennsylvania municipality fills that table in. Ask the borough code office or the contractor what Downingtown’s says.
Rules as read on October 24, 2026. The state’s code edition and the rest of its rules: roof replacement in Pennsylvania.
Homes and roofs in Downingtown
Of 3,526 occupied homes in Downingtown, 1,692 (48%) are owner-occupied. By year built, 21% before 1940, 38% before 1960, 67% before 1980; 22% went up in 2000 or later. (ACS 2020–2024.)
By building type: 22% detached houses, 35% attached single-family houses (rowhouses, twins and townhouses), 9% buildings of two to four units.
With about one in three of homes attached, many roofs here meet a neighbor’s roof at a party wall. Say so on the call, and ask the contractor how the new roof will be tied in where it meets the house next door.
Of the 71 Chester County municipalities on this site, Downingtown has the 9th largest share of homes built before 1980: 67%, against a county range of 12% to 80%.
Downingtown and the towns around it
| Place | Median built | Before 1980 | Owners | Row, twin | Hail days |
|---|---|---|---|---|---|
| Downingtown | 1968 | 67% | 48% | 35% | 14 |
| East Caln | 1995 | 33% | 51% | 15% | 14 |
| Caln | 1981 | 48% | 70% | 25% | 14 |
| East Brandywine | 1996 | 35% | 97% | 18% | 13 |
| West Bradford | 1985 | 39% | 97% | 7% | 15 |
| Uwchlan | 1987 | 32% | 69% | 24% | 14 |
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.
Storm record around Downingtown
NOAA’s storm reports show 14 days since 2006 with hail of at least 1 inch inside a 10-mile circle around Downingtown, topping out at 2 in on August 10, 2008. The most recent was July 14, 2024.
Remnants of Hurricane Ida (DR-4618, September 2021) is the latest of 5 federal storm declarations covering Chester County since 2006. (OpenFEMA.)
A report says hail fell near Downingtown, not that it damaged a roof. When wind or hail damage means a new roof.
What goes on the roof next
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; 22% 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; 21% here predate 1940 | Never a base for a new layer (R908.3.1.1); heavy |
| Flat roof: EPDM or TPO | 15 years | Low-slope roofs and rear sections (35% of homes here are attached) | Coating is not a replacement |
Checking a contractor in Pennsylvania
Before signing for a roof in Downingtown, 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.
Questions about a new roof in Downingtown
Is a permit required for a new roof in Downingtown, PA?
Ask Downingtown first. Under 34 Pa. Code § 403.1(b)(8), alterations to a house that make no structural change are outside the state code. The borough code office can say what Downingtown requires.
Is a roof-over allowed in Downingtown, or is it a tear-off?
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). 67% of Downingtown’s homes were built before 1980; many have been reroofed before.
How old are the houses in Downingtown?
By the Census Bureau’s American Community Survey (2020–2024), the median home in Downingtown was built in 1968, 67% of homes were built before 1980, 48% are owner-occupied.
How many hail days has Downingtown had?
Hail of 1 inch or larger was reported on 14 days within 10 miles of Downingtown from 2006 through 2025 (NOAA Storm Prediction Center). A report means hail fell nearby, not that a roof was damaged.
How do I check a roofing contractor in Downingtown?
Before signing for a roof in Downingtown, 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).
What they will ask on the phone
- The street address in Downingtown, or at least the ZIP code
- Detached, twin or rowhouse, and the number of stories
- What covers the roof now and about when it went on
- The number of layers, if anyone has counted
- Your timing for a complete replacement
- Any historic-district or HOA rules on the house in Downingtown
- That you own the home and decide on the roof
The full list: before you call.