HUD Wind Zones I, II & III Requirements for Manufactured Homes

Every manufactured home built in the United States is assigned to one of three HUD wind zones for manufactured homes, and that rating controls where the home can legally sit, how it must be anchored, and whether it will qualify for federal financing and standard insurance. Zone I is built for basic wind speeds up to 70 mph, Zone II up to 100 mph, and Zone III up to 110 mph. The zones are tiered: a higher-rated home can go into a lower-rated area, but a lower-rated home cannot be placed in a higher-rated one.¹

The Three Zones at a Glance

Federal regulations at 24 CFR 3280.305(c)(2) divide the country by the fastest basic wind speed each area is likely to see.

Zone I covers most of the inland United States. Any county not specifically listed under Zone II or Zone III defaults here.
Zone II covers coastal regions and certain inland areas with higher storm exposure, listed by state and county in the regulation.
Zone III covers the most exposed coastal strips along the Gulf and Atlantic, plus Hawaii and other areas with the highest hurricane potential.

A Zone I home placed in a Zone II or Zone III county is not legal, will fail inspection, and will not qualify for federally backed financing. A Zone III home can go anywhere.¹

How to Confirm Your County’s Zone

The regulation itself names every Zone II and Zone III county and parish. Read the current text of 24 CFR 3280.305(c)(2)(ii) and (iii); if your county appears on neither list, it is Zone I by default.¹ Third-party maps sometimes lag behind revisions, so confirm against the federal text before you buy a home or commit to a site.

What Each Zone Requires of the Home

The zones translate directly into pounds per square foot of pressure the structure must resist. Zone I uses a simple minimum: at least 15 psf of horizontal wind load and 9 psf of net roof uplift. Zone II requires ±39 psf of net horizontal drag on the anchorage and main shearwall systems and 27 psf of uplift. Zone III raises those figures to ±47 psf horizontal and 32 psf uplift, with much higher pressures on roof coverings, trusses near gable ends, and corner wall areas.¹

In practice, Zone I homes use standard framing with conventional fastening patterns. Zones II and III must be designed by a licensed professional engineer or architect and typically feature closer stud spacing, heavier sheathing, reinforced roof-to-wall connections, and windows and doors rated for higher impact and pressure loads. The biggest jump is from Zone I to Zone II, which moves from a prescriptive minimum to a full engineered design.

Anchoring Requirements at the Site

Factory construction only holds up if the home is properly anchored at the installation site. Federal installation standards at 24 CFR Part 3285 set out how anchoring must differ across the three zones.

All three zones require diagonal tie-down straps connecting the frame to ground anchors, but the maximum spacing between straps tightens as the zone number rises. The regulation provides separate spacing tables for each zone based on floor width, I-beam spacing, and the height from grade to the strap attachment point.

The clearest divide is vertical ties. Zone I does not require them. In Zones II and III, every diagonal tie location must also have a vertical tie to resist uplift, and longitudinal ground anchors are required at the ends of each transportable section.²

Soil under the home determines which anchors will actually hold. Federal rules define soil classes from rock and hardpan (Class 1) down to peat and uncompacted fill (Class 5). Class 5 requires evaluation by a licensed engineer, geologist, or architect before any foundation work. If soil testing hasn’t been done and records aren’t available, the installer must assume the weaker classification when selecting anchors.³

The 1,500-Foot Coastline Rule

Even inside Zones II and III, homes placed within 1,500 feet of the coastline face additional requirements. The data plate on every manufactured home carries a warning that the home has not been designed for the higher wind pressures of ocean and coastal areas unless it was specifically engineered for what wind codes call Exposure D conditions. If you plan to site a home that close to the water, both the home and its anchoring system must be designed for those increased loads by a licensed professional engineer.⁴

Proving the Rating: Data Plate and HUD Tag

Two documents attached during manufacturing prove the home’s wind zone rating, and both matter for sales, financing, insurance, and inspections.

The Data Plate

The data plate is a paper label about the size of a standard sheet of paper, permanently affixed inside the home. Common locations are a kitchen cabinet, an electrical panel, or a bedroom closet. It lists the manufacturer’s name, serial number, model, and the specific wind zone, roof load zone, and thermal zone the home was designed for. It also carries a copy of the wind zone map and, for homes not engineered for coastal exposure, the printed 1,500-foot warning.⁴⁵

Lenders, insurers, and local inspectors rely on the data plate. If it’s missing, the home can be very difficult to sell or refinance without a replacement.

The HUD Certification Label

Each transportable section also carries an exterior certification label, commonly called a HUD tag: an etched aluminum plate about two by four inches, attached with blind rivets or drive screws so it can’t be removed without visible damage. It sits at the taillight end of each section, roughly one foot up from the floor and one foot in from the road side. Each label carries a three-letter prefix identifying the inspection agency and a six-digit sequential number that ties the home to its original inspection records. Labels start out red and fade over time.⁶

A missing tag is a warning sign for a buyer. It can indicate the home was altered, a section was replaced, or the label was removed to hide a compliance problem.⁵

If the Documentation Is Missing

For homes built after June 15, 1976, the Institute for Building Technology and Safety (IBTS) maintains records and issues a Performance Certificate showing the serial number, manufacture date, manufacturer, plant location, and original wind zone, roof load zone, and thermal zone. Fees run from $125 for a standard seven-business-day PDF up to $250 for same-day turnaround, with a printed copy available for an additional $10. IBTS does not cover modular homes or homes built before June 15, 1976.⁷ If you’re buying a used home and the seller can’t produce a data plate or tag, ordering the IBTS verification before closing is worth the cost.

Moving a Home to a Different Zone

Relocation brings the wind zone question back. The rule is simple: the home’s rating must meet or exceed the destination’s zone. A Zone I home cannot be moved into a Zone II or Zone III area. A Zone III home can go anywhere. Local code officials at the destination will verify both the home’s construction and the planned installation against federal, state, and local standards, which means checking the data plate and matching the anchoring system to the destination zone.

Don’t assume that a home currently sitting in a Zone I area was built to Zone I standards. It may carry a higher rating. Check the data plate itself rather than inferring from the current location.¹

Insurance and Financing Consequences

Wind zone ratings drive what you pay for insurance and whether federal loan programs will touch the home. In high-wind coastal areas, standard manufactured home policies often exclude windstorm coverage entirely, pushing you to a separate windstorm policy or a state residual market program. Hurricane and named-storm deductibles in those areas are commonly set as a percentage of insured value, typically 2 to 5 percent rather than a flat dollar figure. On a $120,000 home that translates to $2,400 to $6,000 out of pocket before coverage responds.

Documented wind mitigation features can earn discounts the other way. HUD-compliant tie-downs, hurricane straps, and impact-rated windows and doors all count, and having the data plate and certification label on hand speeds underwriting because it proves the home was built to the zone’s specifications.

FHA and other federally backed loan programs require the home to be installed to federal standards, including the correct wind zone rating for its location. A Zone I home sitting in a Zone II county will not qualify for federal mortgage insurance, and lenders who catch the mismatch during appraisal will decline the loan. The problem shows up most often with used homes that a prior owner moved without regard to zone compliance, so verify the rating against the county before you make an offer.

1
eCFR. 24 CFR 3280.305 – Structural Design Requirements
2
eCFR. 24 CFR Part 3285 Subpart E – Anchorage Against Wind
3
eCFR. 24 CFR 3285.202 – Soil Classifications and Bearing Capacity
4
eCFR. 24 CFR 3280.5 – Data Plate
5
U.S. Department of Housing and Urban Development. Manufactured Housing HUD Labels (Tags)
6
eCFR. 24 CFR 3280.11 – Certification Label
7
Institute for Building Technology and Safety (IBTS). Label Verification Reports