Wind Zone Map & Shingle Wind Rating Guide (ASCE 7-22)

✂

Wind Zone Material Advisor

Select your city or enter a design wind speed to get shingle class, nailing, underlayment, and special requirements for your location.

Select City (or choose Custom)

Design Wind Speed (mph)

Roof Shape

🌃

Major City Design Wind Speeds (ASCE 7-22)

Ultimate design wind speeds (V_ult) for Risk Category II residential buildings. These are 3-second gust speeds at 33 feet above ground in Exposure C terrain.

City	State	V_ult (mph)	Zone	Min. Shingle Class
Los Angeles	CA	95	Low	Class D
Phoenix	AZ	95	Low	Class D
Seattle	WA	100	Low	Class D
Denver	CO	110	Moderate	Class F
Dallas	TX	110	Moderate	Class F
Atlanta	GA	110	Moderate	Class F
Chicago	IL	115	Moderate	Class G
New York City	NY	115	Moderate	Class G
Philadelphia	PA	115	Moderate	Class G
Washington	DC	115	Moderate	Class G
Nashville	TN	120	Moderate	Class G
Charlotte	NC	120	Moderate	Class G
Boston	MA	130	High	Class H
Jacksonville	FL	130	High	Class H
Wilmington	NC	130	High	Class H
Charleston	SC	130	High	Class H
Houston	TX	135	High	Class H
Galveston	TX	140	High	Class H
New Orleans	LA	140	High	Class H
Tampa	FL	150	Very High	Class H+
Fort Myers	FL	160	Very High	FL Approved
West Palm Beach	FL	170	Very High	FL Approved
Fort Lauderdale	FL	175	HVHZ	Miami-Dade NOA
Miami	FL	180	HVHZ	Miami-Dade NOA
Miami Beach	FL	185	HVHZ	Miami-Dade NOA
Key West	FL	195	HVHZ	Miami-Dade NOA

Zone Key: Low = ≤105 mph | Moderate = 106-120 mph | High = 121-150 mph | Very High = 151-170 mph | HVHZ = Miami-Dade/Broward 170+ mph. Wind speeds are ultimate (V_ult) per ASCE 7-22 for Risk Category II. Older codes used ASD speeds — multiply by ~0.78 to compare.

🏆

Shingle Wind Rating Classes (ASTM D7158)

ASTM D7158 is the standard test method for wind resistance of asphalt shingles. Shingles are tested using a mechanically applied uplift force and classified into wind speed ratings.

Class D

90 mph

Basic wind resistance for sheltered inland locations.

Standard 4-nail pattern
Felt or synthetic underlayment
Suitable for: Mountain West, Pacific NW interior

Class F

110 mph

Moderate wind resistance for most inland areas.

Standard 4-nail pattern (threshold for 6-nail)
Synthetic underlayment recommended
Suitable for: Most interior US cities

Class G

120 mph

Enhanced wind resistance for moderate wind zones.

6-nail pattern required (>110 mph zones)
Synthetic underlayment required by most codes
Suitable for: Mid-Atlantic, Midwest, upper plains

Class H

150 mph

High wind resistance for coastal and hurricane zones.

6-nail pattern mandatory
Self-adhering underlayment often required
Suitable for: Coastal SE, Gulf, New England coast

Above 150 mph: Standard ASTM D7158 classifications top out at Class H (150 mph). For design speeds above 150 mph (much of coastal Florida), you must use products with specific Florida Product Approvals that have been tested to higher speeds. In the HVHZ (Miami-Dade/Broward), products need a Miami-Dade NOA with large-missile impact testing. Always verify the product's approved wind speed matches or exceeds your site requirement.

🔨

Nailing Requirements by Wind Speed

Wind Speed	Nails/Shingle	Pattern	Additional
≤ 110 mph	4	1" from each end, 2 evenly spaced between	Standard installation
111-150 mph	6	1" from each end, 4 evenly spaced between	Starter strip and hip/ridge also use 6-nail
> 150 mph	6	6-nail per manufacturer's high-wind spec	Product-specific approval; enhanced adhesive may be required
HVHZ (175+ mph)	6+	Per Miami-Dade NOA specifications	Hand-nailing may be required; specific nail type mandated

Why 6 Nails Matters

Increasing from 4 to 6 nails per shingle increases wind resistance by 30-40%. This is because each additional nail creates another point of attachment that must fail simultaneously for the shingle to blow off. The 6-nail pattern also engages the shingle strip below more effectively, creating a stronger interlock between courses. Many manufacturers now require 6-nail installation for their enhanced wind warranties even in areas below 110 mph.

🏙

Wind Exposure Categories

The terrain surrounding your building affects actual wind pressures. ASCE 7-22 defines three exposure categories that modify the base wind speed into actual pressure on your roof.

Exposure B

Urban / Suburban

Areas with buildings, forest, or similar obstructions at least 20 feet tall within 2,630 feet in most directions. Most suburban neighborhoods qualify. This gives the lowest wind pressures for a given speed.

Exposure C

Open Terrain

Flat, open country with scattered obstructions less than 30 feet tall. Farmland, open plains, airport areas. This is the default exposure assumed in wind speed maps and the basis for most code calculations.

Exposure D

Coastal / Flat

Flat, unobstructed areas facing large bodies of water (oceans, Great Lakes). Applies within 600 feet of the shoreline, or further if terrain is flat. This gives the highest wind pressures — 15-30% more than Exposure B.

Practical impact: A home with a 130 mph design speed in Exposure B (suburban) experiences about 15-20% lower wind pressure than the same home in Exposure D (coastal). This is why coastal properties face more damage even at the same rated wind speed — the lack of obstructions allows wind to hit the building at full force.

🏠

Hip vs. Gable Roofs in High Winds

Hip Roof Advantages

40-70% less damage in hurricane-force winds compared to gable roofs
No large flat gable-end wall to catch wind
All four sides slope, deflecting wind over the roof
Lower uplift forces on the leeward slope
Insurance discounts of 5-15% in coastal states
Better structural bracing from additional rafters meeting at the hip

Gable Roof Vulnerabilities

Gable end wall acts as a sail, catching wind and creating enormous pressure
Failure mode: wind pushes gable wall inward, collapsing the entire end
Higher uplift on windward slope, suction on leeward
Ridge line perpendicular to wind creates maximum uplift
Overhangs at gable ends are vulnerable to peeling
Can be braced/reinforced but never as aerodynamic as hip

If You Have a Gable Roof in a Wind Zone

Brace the gable end: Install horizontal and diagonal bracing per FEMA P-804 guidelines
Limit overhang: Keep gable overhangs under 12 inches or add metal bracing
Use ring-shank nails: Provide 40% more withdrawal resistance than smooth-shank
Add hurricane straps: Connect rafters/trusses to wall top plates with metal connectors
Seal the deck: Use self-adhering underlayment as secondary water barrier in case shingles fail

☀

Florida Roofing Requirements

Florida has the most stringent wind-related roofing codes in the US, with two tiers: the general Florida Building Code (FBC) and the High Velocity Hurricane Zone (HVHZ) requirements.

Florida Building Code (FBC) — Statewide

Product approval: All roofing products must carry a Florida Product Approval (FL#) number
Underlayment: Self-adhering modified bitumen required in many coastal areas; minimum ASTM D226 Type II or equivalent statewide
Enhanced nailing: 6-nail pattern required for shingles in most of the state (>110 mph)
Roof deck attachment: 8d ring-shank nails at 6" o.c. along edges, 6" o.c. in field (enhanced schedule for higher wind zones)
Secondary water resistance: Required for new roofs in areas with V_ult > 130 mph — sealed deck or self-adhering underlayment
Permits & inspections: Required for all roof replacements; contractor must be licensed

HVHZ — Miami-Dade & Broward Counties

Product approval: Must carry a Miami-Dade Notice of Acceptance (NOA) — Florida Product Approval alone is NOT sufficient
Impact testing: Products must pass large-missile impact testing (TAS 201, TAS 202, TAS 203)
Wind speeds: 175-195 mph ultimate design speeds
Nail type: Specific nail specifications per product NOA; hand-nailing may be required
Self-adhering underlayment: Full deck coverage required
Inspection: Requires inspection at multiple stages (deck, underlayment, final)
Re-roofing: No layovers — complete tear-off required

★

Texas Coastal (TWIA) Requirements

WPI-8 Certificate

The Texas Windstorm Insurance Association (TWIA) covers the 14 first-tier coastal counties and parts of Harris County. To obtain or maintain windstorm insurance, you need a WPI-8 certificate proving your roof meets the Texas Department of Insurance windstorm building code.

14 TWIA First-Tier Counties:

Aransas, Brazoria, Calhoun, Cameron, Chambers, Galveston, Jefferson, Kenedy, Kleberg, Matagorda, Nueces, Refugio, San Patricio, Willacy

Key TWIA Roofing Requirements

Wind rating: Shingles must be rated for the local design wind speed (typically 130-140 mph coastal)
Nailing: 6-nail pattern with specific nail specifications
Deck attachment: Enhanced nailing schedule — 8d ring-shank at 4" o.c. along edges
Underlayment: ASTM D226 Type II minimum; self-adhering recommended for higher wind areas
Inspection: Licensed WPI-8 inspector must verify before roofing begins and after completion
Documentation: Keep copies of all product data sheets, inspection certificates, and photos

🌴

Carolina Coast Requirements

North Carolina

Coastal counties: Design speeds 130-150 mph (Outer Banks highest)
NC Building Code: Based on IRC/IBC with ASCE 7-22 wind maps
6-nail pattern: Required for areas >110 mph (most of coastal NC)
Fortified Home: IBHS Fortified designation increasingly popular; some insurers require it for new policies
Sealed roof deck: Required in areas >130 mph — self-adhering underlayment or taped deck seams
Ring-shank nails: Required for roof deck attachment in high-wind areas

South Carolina

Coastal counties: Design speeds 130-145 mph (Charleston to Myrtle Beach)
SC IRC amendments: Enhanced wind provisions for coastal counties
Fortified construction: SC Safe Home program provides up to $1,000 matching grants for Fortified Roof upgrades
Underlayment: Enhanced underlayment required within 10 miles of coast
Insurance incentive: SC law requires insurers to offer wind mitigation discounts for certified improvements

Related Resources

Snow Load Map & Calculator Roofing Nail Patterns Building Code Requirements Roofing Material Weights Storm Damage Guide Insurance Claims Guide

❓

Frequently Asked Questions

What wind speed is my area rated for?

Wind speeds are defined by ASCE 7-22 ultimate design wind speed maps. Interior US locations typically range from 95-115 mph, moderate inland areas 110-120 mph, Atlantic coast 110-130 mph, Gulf Coast 130-170 mph, and South Florida 170-195 mph. Your local building department has the exact value for your address. These are 3-second gust speeds with a 700-year return period for Risk Category II buildings.

What shingle wind rating do I need?

Match your shingle wind class to your local design wind speed: Class D (ASTM D7158) is rated to 90 mph, Class F to 110 mph, Class G to 120 mph, and Class H to 150 mph. For areas above 150 mph, you need products with specific Miami-Dade NOA or Florida Product Approval. Always choose a class that meets or exceeds your local requirement — going one class higher provides a valuable safety margin.

What is the difference between 4-nail and 6-nail patterns for wind?

The standard 4-nail pattern is approved for wind zones up to 110 mph. Above 110 mph, building codes require a 6-nail pattern (sometimes called high-wind nailing), which increases wind resistance by 30-40%. Six nails are placed evenly across the shingle's nailing zone — 1 inch from each end with 4 nails evenly spaced between. Many manufacturers require 6-nail patterns for their enhanced wind warranties regardless of location.

Are hip roofs better than gable roofs in high winds?

Yes, significantly. Studies from hurricanes show that hip roofs sustain 40-70% less damage than gable roofs in the same wind event. Hip roofs have slopes on all four sides, which deflects wind more effectively and eliminates the large flat gable-end wall that acts as a sail. Insurance companies in coastal areas often offer premium discounts of 5-15% for hip roofs. If you're building new in a high-wind area, a hip roof is strongly recommended.

What is the Florida HVHZ and why does it matter?

The High Velocity Hurricane Zone (HVHZ) covers Miami-Dade and Broward counties in South Florida, where design wind speeds reach 175-195 mph. Products installed in the HVHZ must carry a Miami-Dade Notice of Acceptance (NOA), which requires passing the most rigorous wind testing in the US — including large-missile impact testing. HVHZ requirements are stricter than even the Florida Building Code's general high-wind provisions and often serve as a benchmark nationwide.

Do I need special underlayment in high-wind areas?

Yes. In areas with design wind speeds above 120 mph, codes typically require self-adhering modified bitumen underlayment (peel-and-stick) rather than standard felt or synthetic. In HVHZ and many coastal areas, the entire roof deck must be covered with self-adhering underlayment as a secondary water barrier. This protects the home if shingles are torn off during a storm. Some jurisdictions also require enhanced underlayment in the first 4-6 feet from eaves and rakes.

What is a Texas TWIA WPI-8 certificate?

The Texas Windstorm Insurance Association (TWIA) requires a WPI-8 certificate for properties in the 14 coastal counties and certain other designated areas. This certificate confirms that the roof meets the Texas Department of Insurance windstorm building code requirements. Without a valid WPI-8, you cannot obtain windstorm insurance through TWIA. A licensed inspector must verify the installation and issue the certificate. Requirements include specific fastening patterns, product approvals, and installation methods.

How do exposure categories affect wind load?

Exposure categories (B, C, D) describe the terrain roughness around a building and significantly affect actual wind pressures. Exposure B (urban/suburban with many obstructions) reduces wind pressure compared to the base value. Exposure C (open terrain with scattered obstructions) is the baseline for most wind speed maps. Exposure D (flat coastal areas facing open water) increases wind pressure by 15-30% compared to Exposure B. Your actual wind pressures depend on both the design wind speed and exposure category.

US Wind Zone Map & Shingle Wind Rating Guide