Key Takeaways
- • Boston — wood roofing banned since 1895. No untreated cedar; limited FR-cedar exceptions in landmark districts.
- • Cambridge, Brookline, Newton, Somerville — Class A assembly required citywide; FR-treated cedar often accepted in historic districts.
- • Class A = UL 790 / ASTM E108 highest fire rating (max 6 ft flame spread, withstands 12 lb brand).
- • Synthetic shake leaders: DaVinci Multi-Width, CertainTeed Presidential, GAF Camelot II, Inspire Classic Shake, Brava Shake & Slate.
- • Class A upgrade earns 5–12% HO-3 insurance premium discount.
- • Historic districts under MGL Ch. 40C can override and require original cedar preservation.
In This Guide
Boston's 1895 Wood-Roof Ban
Boston's ordinance banning wood roofing dates to 1895, enacted after a series of 19th-century roof-propagated fires including the catastrophic Great Fire of 1872 which destroyed 776 buildings and most of Boston's commercial district. The ordinance categorically prohibits wood shake and wood shingle roofing on buildings within city limits regardless of treatment level. Boston Inspectional Services Department (ISD) actively enforces the ban at permit issue; wood roofing permits are denied outright.
The narrow exceptions are formally designated landmark-district renovations (Beacon Hill, Bay Village, Bulfinch Triangle, Back Bay) where historic-material preservation can be approved case-by-case through the Boston Landmarks Commission plus an ISD waiver. Those approvals are rare and require architectural documentation of original cedar as a character-defining feature. See ourBoston historic-district roof permit guide for the landmark renovation process.
For conventional Boston re-roofs, the accepted product categories are: synthetic polymer shake (DaVinci, Inspire, Brava), heavy-profile architectural asphalt with shake silhouette (CertainTeed Presidential, GAF Camelot II), slate, clay/concrete tile, standing-seam metal, or low-slope membrane.
MA Cities Requiring Class A
In addition to Boston's total wood ban, four other MA cities impose a citywide Class A fire-rating requirement that effectively excludes untreated cedar shake:
| City | Cedar Rule | FR-Cedar Exception | Historic Override |
|---|---|---|---|
| Boston | All wood roofing banned (1895) | Landmark only | Landmarks Commission |
| Cambridge | Class A required | Yes, with assembly rating | Old Cambridge, East Cambridge |
| Brookline | Class A required | Yes, in local historic dist. | Cottage Farm, Chestnut Hill |
| Newton | Class A (ISD) | Yes, in historic dist. | Newton Upper Falls, Auburndale |
| Somerville | Class A required | Yes, with docs | Some districts |
Other cities (Quincy, Medford, Watertown, Arlington, Lexington) default to the state 780 CMR minimum of Class B or C. Cedar is legal in those jurisdictions with standard underlayment and installation.
UL 790 Class A / B / C Explained
UL 790 (superseded by ASTM E108, but still commonly referenced) classifies roofing assemblies by three standardized fire tests: spread of flame, intermittent flame exposure, and burning-brand test. All tests are done on complete roof assemblies (covering + underlayment + deck + fasteners), not just the covering material alone.
| Class | Max Flame Spread | Burning Brand | Typical Materials |
|---|---|---|---|
| Class A | 6 ft | 12 lb brand | Slate, tile, metal, Class-A asphalt, FR cedar w/ Class A underlayment |
| Class B | 8 ft | 4 lb brand | Some FR-treated cedar, certain architectural asphalt lines |
| Class C | 13 ft | 4 oz brand | Untreated cedar shake, basic 3-tab asphalt |
An untreated cedar shake roof is Class C on its own but can achieve a Class Aassembly rating when paired with a Class A-rated underlayment (GAF VersaShield, CertainTeed FireOut SolidStart, DensGlass fiber-mat gypsum) and fastener system listed with the covering. This is how some MA cities allow real cedar in historic-preservation cases while still meeting the Class A requirement.
Price an Allowed Roof for Your City
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FR-Treated Cedar (CCA / CDP)
Fire-retardant-treated real cedar comes in two treatment families:
- • CCA (Chromated Copper Arsenate)— pressure-treated with a copper-based solution. Achieves Class B on its own, Class A with compliant underlayment. Widely available; CCA cedar is the default specification when preserving the look of real cedar is required.
- • CDP (Chemonite / Ammoniacal Copper Zinc Arsenate)— alternative non-arsenic pressure treatment. Similar fire performance, less environmental concern.
The most commonly specified FR-treated cedar product in Massachusetts in 2026 is FireFree by Chemco, which uses CCA-treated Alaskan yellow cedar with a 25-year material warranty and 10-year fire-retardant warranty. Installed cost in MA runs $16–$20 per sqft, about 15 percent above untreated cedar ($14–$18). Lifespan is roughly equivalent to untreated cedar (25 years) but with significantly improved fire performance.
FR-treated cedar is accepted in Cambridge, Brookline, Newton, and Somerville when paired with a Class A assembly rating. Boston ISD generally does not accept FR cedar as a substitute for non-combustible materials outside of formal landmark waivers.
Synthetic Shake Alternatives
Synthetic shake products solve the look-of-cedar problem while delivering Class A fire performance, higher wind ratings, and longer warranties. 2026 leading options:
| Product | Type | Class | Wind | Life | Cost/sqft |
|---|---|---|---|---|---|
| DaVinci Multi-Width Shake | Polymer composite | A | 110 mph | 50 yr | $13 |
| Inspire Classic Shake | Polymer composite | A | 110 mph | 50 yr | $14 |
| Brava Shake & Slate | Polymer composite | A | 110 mph | 50 yr | $15 |
| CertainTeed Presidential Shake TL | Heavy asphalt | A | 110 mph | 40 yr | $9 |
| GAF Camelot II | Heavy asphalt | A | 110 mph | 40 yr | $8 |
| Malarkey Windsor | Heavy asphalt | A | 110 mph | 30 yr | $8 |
Polymer composites (DaVinci, Inspire, Brava) deliver the best visual match with cedar and the longest warranty, at a 40-70 percent premium over heavy asphalt. Heavy-profile asphalt (Presidential, Camelot II) is the best economic choice for Boston, Cambridge, and other Class-A-mandate cities when the cedar look is desired but budget is constrained.
Cedar Alternative Finder
Pick your MA city, your cedar-look preference, and your budget tier. The tool filters to products legal in your city and returns fire-rating, wind-rating, lifespan, and cost-per-sqft.
Cedar Alternative Finder
Pick your MA city, whether you want the cedar-shake look, and your budget tier. Get a filtered list of allowed products with fire-rating, wind-rating, and cost-per-sqft.
Newton Rules
Fire rating minimum: Class A · Real cedar: FR-treated only · historic districts may override
ISD (Inspectional Services Dept) requires Class A materials. FR-treated cedar allowed in Newton Upper Falls, Newton Centre, and Auburndale historic districts. Synthetic preferred elsewhere.
Allowed Products (4)
DaVinci Roofscapes Multi-Width Shake
Polymer composite; most visually accurate cedar-shake substitute.
Class A
110 mph · 50 yr
$13/sqft
CertainTeed Presidential Shake TL
Heavy-profile asphalt that mimics hand-split shake.
Class A
110 mph · 40 yr
$9/sqft
GAF Camelot II
Architectural shingle with shake silhouette; widely stocked.
Class A
110 mph · 40 yr
$8/sqft
Inspire Roofing Classic Shake
Composite polymer; textured like split shake.
Class A
110 mph · 50 yr
$14/sqft
Illustrative guidance based on MA municipal building codes and historic-district rules. Confirm current requirements with your local ISD (Inspectional Services) or building department before specifying product.
Historic District Overrides
Local historic districts operating under Massachusetts General Law Chapter 40C (the Historic Districts Act) can override or modify the citywide cedar rules in specific preservation contexts. Key overrides in 2026:
- • Beacon Hill Historic District (Boston) — Boston Landmarks Commission can approve FR-treated cedar with ISD waiver on a case-by-case basis for original-cedar preservation.
- • Old Cambridge + East Cambridge — FR-treated cedar accepted when the home is a contributing historic resource.
- • Brookline Cottage Farm, Chestnut Hill, Graffam-McKay — FR-treated cedar accepted with Class A underlayment.
- • Newton Upper Falls, Newton Centre, Auburndale — FR cedar accepted with architectural documentation.
- • Old King's Highway (Cape Cod) — real untreated cedar often required for visible roof planes; not subject to Boston-style bans.
The pattern is: historic districts can up-require(force cedar where it wouldn't otherwise be mandated) and waive (allow FR cedar where non-combustible is otherwise mandated), but they cannot override health-and-safety minimums in citywide codes without formal building-official concurrence.
Class A Insurance Discount
Massachusetts HO-3 carriers offer documented premium discounts for Class A roofing, typically 5–12 percent on the wind-and-hail portion of the policy and 3–7 percent on the total premium. Carriers that publish explicit Class A credits in MA include MAPFRE, Safety, Vermont Mutual, Arbella, Plymouth Rock, Amica, and Travelers.
To claim the credit, submit to your agent or carrier: (1) the UL 790 / ASTM E108 Class A product sheet from the manufacturer, (2) the installer invoice showing the product SKU, and (3) the town building-department certificate of completion. Credit typically applies at next renewal, not mid-policy. On a $2,400 annual MA HO-3 policy, a Class A upgrade from Class C typically saves $120–$290/year in recurring premium, which compounds to $3,000–$7,250 in present-value savings over a 25-year roof life. For many MA homeowners the insurance savings alone justify the Class A premium.
Frequently Asked Questions
Frequently Asked Questions
Is real cedar shake legal anywhere in Massachusetts?
Yes, real untreated cedar shake is legal in most Massachusetts cities and towns outside of Boston, Cambridge, Brookline, Newton, and Somerville. State 780 CMR requires a Class C minimum fire rating for residential roofing, and untreated Western red cedar shake meets Class C when properly installed with Class A underlayment. The real-cedar hotspots are Cape Cod (where it's required by historic districts), the North Shore coastal towns (Manchester-by-the-Sea, Marblehead, Rockport, Gloucester), the Berkshires, the South Shore outside of Quincy, MetroWest outside of Newton, and virtually all of Western Mass. Roughly 250 of Massachusetts' 351 municipalities allow untreated cedar on at least some roof types.
What are the Class A, B, and C fire ratings?
UL 790 (now ASTM E108) classifies roofing assemblies based on three standardized tests: spread of flame, intermittent flame exposure, and burning-brand test. Class A is the most stringent (flame spread 6 ft or less, withstands brands up to 12 lb). Class B is moderate (flame spread 8 ft, brands up to 4 lb). Class C is the basic level (flame spread 13 ft, brands up to 4 oz). Most MA cities require Class B minimum under 780 CMR or local amendment; the cities with densest urban fabric (Boston, Cambridge, Brookline, Newton, Somerville) require Class A. Note that 'Class A' often refers to the whole assembly, not just the covering. Untreated cedar shake is Class C on its own but can achieve Class A assembly rating when paired with a Class A-rated underlayment system (GAF VersaShield, CertainTeed FireOut) and appropriate fasteners.
Are FR-treated cedar shakes accepted in Boston?
Boston's 1895 fire ordinance banning wood roofing is still actively enforced by the Inspectional Services Department (ISD). Boston ISD does not accept FR-treated (CCA, CDP, or ammonium-phosphate-treated) cedar as a substitute for non-combustible roofing in most neighborhoods; the ordinance targets the material category (wood), not the fire rating. Narrow exceptions exist for formally designated landmark-district renovations (Beacon Hill, Bay Village, Bulfinch Triangle, Back Bay) where preservation of original cedar can be approved case-by-case through the Boston Landmarks Commission and ISD. For new-construction and non-landmark renovation work in Boston, the accepted options are synthetic shake (DaVinci, CertainTeed Presidential, GAF Camelot II, Inspire, Brava), architectural asphalt with shake silhouette, slate, clay/concrete tile, or metal.
Do synthetic shakes really look like cedar at ground level?
Modern polymer composite shakes (DaVinci Multi-Width, Inspire Classic, Brava Shake & Slate) are visually indistinguishable from hand-split cedar shake at ground level and up to about 15 feet. Zoom photographs at close range show subtle differences: the composite versions have slightly more uniform texture repeats, and the edge detail is cleaner (no splits or weathering checks). At more than 15 feet away, no one can tell the difference. Heavy-profile asphalt (CertainTeed Presidential Shake TL, GAF Camelot II) is a step down in realism — you can tell it's asphalt at 10-15 feet, but the overall roof silhouette and shadow-line still read as shake. The trade-off is price: polymer composites run $13-$18/sqft installed; heavy-profile asphalt runs $8-$12/sqft; real cedar runs $14-$22/sqft.
Can historic districts require me to keep real cedar?
Yes. Even in cities that restrict real cedar citywide, local historic districts operating under MGL Chapter 40C can require preservation of original materials, including cedar shake, as a condition of Certificate of Appropriateness. This is most common on the North Shore (Marblehead Historic District, Old Essex County), in Cape Ann (Rockport, Gloucester Annisquam), Lexington's Battle Green area, Concord's Barrett Farm district, and in Western Mass historic villages (Old Deerfield, Old Sturbridge area). In those districts, FR-treated cedar (CCA or CDP pressure-treated) is often the negotiated compromise: original appearance with modern fire performance. Your local historic commission publishes a material guide; always pull it before finalizing scope.
Does Class A earn an insurance premium discount?
Yes, typically 5-12 percent on the wind-and-hail portion of an HO-3 policy, and 3-7 percent on the total premium. Massachusetts insurers (MAPFRE, Safety, Vermont Mutual, Arbella, Plymouth Rock, Amica, Travelers) all offer a Class A credit when documented at policy underwriting or renewal. Submit the manufacturer product sheet showing UL 790 Class A, the CRRC cool-roof certificate if applicable, and the installer invoice. On a $2,400 annual HO-3 policy, a Class A upgrade from Class C typically saves $120-$290/year in recurring premium, which over a 25-year roof life amounts to $3,000-$7,250 in present-value savings — often more than the upcharge from standard cedar to a Class A synthetic.
What are the best synthetic shake products on the market in 2026?
Top 2026 options by category: (1) Polymer composite — DaVinci Roofscapes Multi-Width Shake (the category standard; 50-yr warranty, Class A, 110 mph); Inspire Roofing Classic Shake (50-yr, Class A, 110 mph); Brava Shake & Slate (50-yr, Class A, 110 mph, available in shake or slate profile). (2) Heavy-profile asphalt — CertainTeed Presidential Shake TL (40-yr, Class A, 110 mph, most widely stocked in MA); GAF Camelot II (40-yr, Class A, 110 mph, architectural shingle with shake silhouette); Malarkey Windsor (30-yr, Class A, 110 mph). (3) FR-treated real cedar — FireFree by Chemco (CCA/CDP pressure-treated Alaskan yellow cedar; Class A assembly with compliant underlayment; 25-yr life in MA climate). Always verify the current product SKU class rating because manufacturers offer both standard and Class A versions of the same-looking product.
How does the fire-rating requirement interact with Cape Cod historic districts?
Cape Cod towns are not subject to the Boston or Newton Class A citywide mandates. State 780 CMR minimum (Class C) applies on the Cape, and most Cape municipalities do not impose a Class B or Class A overlay. However, Old King's Highway Regional Historic District (Sandwich, Barnstable, Yarmouth, Dennis, Brewster, Orleans north of Route 6) may require cedar shake for visible roof planes regardless of fire rating. The result: Cape Cod homeowners usually install untreated Western red cedar or Alaskan yellow cedar to satisfy historic review, knowing it's only Class C. Class A upgrade paths on the Cape are (a) pair with a Class A underlayment system, or (b) substitute FR-treated cedar or polymer composite shake that satisfies both historic visual review and Class A. See our Cape Cod roof replacement cost guide for town-by-town detail.