Permit
Expect a building permit
The residential code’s permit-exempt list (R105.2) has no roofing line. The application to Westwood’s building department carries the contractor’s HIC number (R105.3).
Roof Replacement in Westwood, MA
The median home in Westwood was built in 1968; there are 5,796 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.
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 Westwood
Layers
One old layer can stay; two cannot
IRC R908.3.1.1 forbids roofing over two existing layers, over slate or tile, or over a water-soaked roof. With 64% of Westwood’s homes were built before 1980, ask what is under the newest layer.
Source: IRC 2021, Chapter 9 (Pennsylvania edition, UpCodes); 780 CMR 51.00, Chapter 9 amendments
Ice barrier
Required statewide
Massachusetts answers “yes” to the ice barrier for every town. It runs from the eave to 24 inches inside the exterior wall, more on steep roofs (IRC R905.1.2); check that the quote lists it.
Source: 780 CMR 51.00, Chapter 3 amendments (Tables R301.2(1) and R301.2(2)); IRC 2021, Chapter 9 (Pennsylvania edition, UpCodes)
Wind and snow
121 mph design wind, 40 psf ground snow
Westwood’s code design values are a 121 mph ultimate design wind speed and a 40 psf ground snow load (35 psf minimum flat-roof snow load). At that wind speed the code calls for asphalt shingles labeled ASTM D7158 Class G or H (Table R905.2.4.1).
Source: 780 CMR 51.00, Chapter 3 amendments (Tables R301.2(1) and R301.2(2)); IRC 2021, Chapter 9 (Pennsylvania edition, UpCodes) (780 CMR 51.00, Table R301.2(2))
Rules as read on October 24, 2026. The state’s code edition and the rest of its rules: roof replacement in Massachusetts.
Homes and roofs in Westwood
87% of the occupied homes in Westwood are lived in by their owners: 4,882 households, the people this line is for. By year built, 17% before 1940, 40% before 1960, 64% before 1980; 16% went up in 2000 or later. (ACS 2020–2024.)
By building type: 79% detached houses.
Of the 28 Norfolk County municipalities on this site, Westwood has the 13th largest share of homes built before 1980: 64%, against a county range of 41% to 86%.
ZIP codes: 02090
Westwood and the towns around it
| Place | Median built | Before 1980 | Owners | Row, twin | Hail days |
|---|---|---|---|---|---|
| Westwood | 1968 | 64% | 87% | 2% | 10 |
| Norwood | 1960 | 72% | 54% | 7% | 11 |
| Dedham | 1956 | 76% | 73% | 5% | 13 |
| Dover | 1970 | 61% | 98% | 2% | 9 |
| Needham | 1965 | 64% | 83% | 5% | 10 |
| Medfield | 1970 | 64% | 86% | 5% | 11 |
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 Westwood
Within 10 miles of Westwood, hail of an inch or more was reported on 10 days between 2006 and 2025, the biggest stones 2 in on August 4, 2015. The most recent was August 15, 2024.
Severe Winter Storm and Snowstorm (DR-4651, April 2022) is the latest of 8 federal storm declarations covering Norfolk County since 2006. (OpenFEMA.)
A report says hail fell near Westwood, not that it damaged a roof. When wind or hail damage means a new roof.
What goes on the roof next
Lifespans come from HUD’s capital-needs table, not from a brochure. 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; 79% of homes here are detached | Class G or H at 121 mph design wind (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; 17% here predate 1940 | Can’t be roofed over; check the framing for the weight |
| Flat roof: EPDM or TPO | 15 years | Porches, additions, low-slope rears | Seams at walls and drainage |
Checking a contractor in Massachusetts
For an owner-occupied home of one to four units in Westwood, the contractor must be registered under the home improvement law (M.G.L. c. 142A), and a construction supervisor licensed (CSL) for roof covering supervises a permitted reroof. Ask for both numbers.
The price side is in what a new roof costs in Massachusetts; the paperwork side in checking a roofing contractor.
Questions about a new roof in Westwood
Does a roof replacement in Westwood need a permit?
Expect a building permit. The residential code’s permit-exempt list (R105.2) has no roofing line. The application to Westwood’s building department carries the contractor’s HIC number (R105.3).
Can a new roof go over the old one in Westwood?
IRC R908.3.1.1 forbids roofing over two existing layers, over slate or tile, or over a water-soaked roof. With 64% of Westwood’s homes were built before 1980, ask what is under the newest layer.
How old are the houses in Westwood?
By the Census Bureau’s American Community Survey (2020–2024), the median home in Westwood was built in 1968, 64% of homes were built before 1980, 87% are owner-occupied.
How many hail days has Westwood had?
Hail of 1 inch or larger was reported on 10 days within 10 miles of Westwood 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 Westwood?
For an owner-occupied home of one to four units in Westwood, the contractor must be registered under the home improvement law (M.G.L. c. 142A), and a construction supervisor licensed (CSL) for roof covering supervises a permitted reroof. Ask for both numbers.
What they will ask on the phone
- The street address in Westwood, or at least the ZIP code
- The number of stories, and whether the house stands alone
- What covers the roof now and about when it went on
- Whether there is one layer or more, if you know
- That you want a new roof or a full replacement, and when you want the work done
- Any historic-district or HOA rules on the house in Westwood
- That you are the owner and the one who decides
The full list: before you call.