Mobile Home Foundations: Types, Rules and What Lenders Require

A mobile home foundation is the system of footings, piers and anchors, or the concrete slab, wall or basement, that carries the home’s weight to the ground and holds it down in high wind. Every new manufactured home needs one that meets federal installation rules. Only some foundations count as “permanent,” and that distinction decides whether you can get a mortgage.

A note on words. In law, a “mobile home” is a factory-built home made before the federal HUD Code took effect on June 15, 1976. Everything built since is a “manufactured home.” Most people still say mobile home for both, and search for a mobile home foundation when they mean either, so this guide uses the terms the way buyers search for them and flags it where the difference matters.

Here you will find the main foundation types and what each is good for, the federal rules installers must follow, what FHA, Fannie Mae, USDA and VA lenders require, and how wind and frost change the job from one county to the next. We also matched 2025 Census shipments of new homes against HUD’s wind zones: more than half of all new manufactured homes went to the 13 states that have hurricane-zone counties.

Mobile home foundations: the numbers in short

Mobile home foundation types: from piers to basements

Most manufactured homes sit on piers under the steel frame, set on footings and tied to ground anchors; the alternatives are a perimeter wall, a concrete slab or a basement. All of them can be built to the federal installation standards. The difference is cost, how the home looks from the street, how it handles your soil and climate, and whether a lender will treat it as a permanent foundation.

	What it is	Good for	Watch out for
Piers and ground anchors	Concrete block or steel piers under the frame and mating line, on concrete, ABS or treated-wood pads, with straps to anchors screwed into the ground	The lowest-cost setup; homes financed with a chattel loan or paid in cash	Usually not a permanent foundation for a mortgage unless an engineer certifies the system; footings must still clear the frost line
Engineered pier system	Manufactured steel or concrete pier and bracing systems designed and tested to resist wind and seismic loads	Getting a permanent-foundation certification without pouring a full wall or slab	Must be installed exactly as its listing and the engineer require; ask whether it is accepted for FHA or conventional loans
Perimeter wall (crawl space)	A continuous poured concrete or masonry wall on a footing around the home, often with interior piers	A site-built look; required by some zoning codes and by Fannie Mae’s MH Advantage	More concrete and labor; needs vents and drainage so the crawl space stays dry
Concrete slab	A reinforced slab, often with thickened edges, with anchor points cast in	Firm, level support on stable soil in mild climates	Above the frost line it must be engineered for the site; poor drainage under a slab is hard to fix later
Full or partial basement	Poured or block basement walls with the home set on top, usually by crane	The most site-built result and extra living or storage space	The highest cost; the home must be designed or approved for basement placement

Whatever the type, a mobile home foundation has to carry the loads printed on the home’s data plate, the label inside the home that lists the wind zone, roof load zone and thermal zone it was built for. That label, not the brochure, tells the installer and engineer what the foundation must resist.

What the federal installation rules require

New manufactured homes must be installed to HUD’s Model Manufactured Home Installation Standards, 24 CFR Part 3285, or to a state program that meets or exceeds them. The manufacturer’s installation manual adds the details for each model. These are the rules that shape the foundation most directly:

• Footings on firm ground. Footings sit on undisturbed soil or fill compacted to 90% of its maximum density, and each pier needs its own footing.
• Below the frost line. In freezing climates, conventional footings must go below the local frost depth. A slab or insulated foundation can stay above it only if a registered engineer or architect designs it for the site.
• Pier height limits. Under 36 inches, single concrete blocks with cells vertical are allowed. From 36 to 67 inches, piers must be double, interlocked blocks. Above 67 inches, an engineer or architect must design them.
• Anchoring against wind. After the home is leveled, it must be secured with anchor assemblies or tied into an approved foundation system that resists the wind loads on its data plate.
• Licensed installer and inspection. Each state runs its own installation program or falls under HUD’s. In HUD-run states the installer needs a HUD license and every installation is inspected before the home is occupied.

Local governments add their own layer: a placement or building permit, setbacks, and sometimes a required perimeter wall or skirting. Federal law governs how the home is built; where it can go and what it must look like on the lot are still local decisions, so the county permit office is the first call.

Which mobile home foundation your loan needs

Any mortgage on a manufactured home and its land expects a permanent foundation, while a chattel loan on the home alone usually does not. Each program words the rule differently, and the details below decide what you build or what you inspect before buying.

The foundation is only half of it. To qualify as real estate, the home usually also has to be titled with the land under your state’s procedure. Our guide to putting a manufactured home on rural land explains the title step and the loan options side by side.

Wind zones, roof loads and frost: why the county matters

The same home needs a different foundation and anchoring in coastal Louisiana than in central Missouri, because HUD sets wind and snow loads by location. Every home is built for one wind zone, one roof load zone and one thermal zone, and it may only be installed where those match.

• Wind Zone I. Most of the country. Homes are designed for standard wind loads, and anchoring follows the manufacturer’s manual.
• Wind Zone II, 100 mph. Listed coastal counties in Alabama, Georgia, Louisiana, Maine, Massachusetts, Mississippi, North Carolina, South Carolina, Texas and Virginia, plus most of Florida.
• Wind Zone III, 110 mph. All of Hawaii, coastal Alaska and listed counties in Florida, Louisiana and North Carolina. Anchoring and the connection to the foundation carry far higher loads here.

Snow works the same way through three roof load zones, 20, 30 and 40 pounds per square foot, and frost works through footing depth. In northern states, footings that stop short of the frost line can heave in winter, which shows up as doors that stick, cracked drywall and a floor that is no longer level. That is why the frost depth from your county building office belongs in the installer’s quote.

Where new homes go, and the wind they have to handle

To see where mobile home foundation and anchoring rules matter most, we compared two public sources: the Census Bureau’s count of new manufactured homes shipped to each state in 2025, and HUD’s list of counties in Wind Zones II and III. We also divided shipments by each state’s housing stock from the 2024 American Community Survey, which shows where factory-built homes are a bigger part of what is being added.

The result is lopsided. Texas alone received 17,458 new homes, about 17% of the national total. Mississippi added 29.4 new manufactured homes for every 10,000 existing housing units, more than four times the national rate of 7.0, followed by Alabama, Louisiana and South Carolina. All four have counties in HUD’s high-wind zones.

Read the table with two cautions. Shipments are counted by state, not county, so a home shipped to Texas may well have gone to a Wind Zone I county far from the coast. And a high shipment rate says nothing about price: it reflects how much of each state’s new housing is factory-built.

Rank	State	New homes shipped, 2025	Per 10,000 housing units	Share of homes that are mobile or manufactured	HUD wind zones in the state
1	Mississippi	3,994	29.4	14.0%	Zone II: 6 counties
2	Alabama	5,314	22.3	11.6%	Zone II: 2 counties (Baldwin, Mobile)
3	Louisiana	4,607	21.5	12.2%	34 parishes: 26 Zone II, 8 Zone III
4	South Carolina	5,232	20.7	12.8%	Zone II: 9 counties
5	Kentucky	3,800	18.5	10.3%	Zone I statewide
6	New Mexico	1,647	16.9	15.0%	Zone I statewide
7	Oklahoma	2,584	14.4	8.0%	Zone I statewide
8	Texas	17,458	13.8	6.2%	Zone II: 15 coastal counties
9	West Virginia	1,133	13.1	13.2%	Zone I statewide
10	Arkansas	1,831	12.9	10.5%	Zone I statewide
11	Maine	985	12.9	8.2%	Zone II: 2 counties (Hancock, Washington)
12	North Carolina	6,269	12.4	10.4%	19 counties: 16 Zone II, 3 Zone III
13	Tennessee	3,829	11.8	7.5%	Zone I statewide
14	Wyoming	310	11.0	11.3%	Zone I statewide
15	Georgia	4,807	10.3	7.4%	Zone II: 6 coastal counties
16	South Dakota	385	9.1	7.2%	Zone I statewide
17	North Dakota	294	7.7	5.7%	Zone I statewide
18	Michigan	3,555	7.6	5.0%	Zone I statewide
19	Montana	408	7.6	9.6%	Zone I statewide
20	Oregon	1,387	7.3	6.7%	Zone I statewide
21	Arizona	2,236	6.8	9.0%	Zone I statewide
22	Delaware	322	6.8	7.3%	Zone I statewide
23	Indiana	2,028	6.7	4.2%	Zone I statewide
24	Florida	6,804	6.4	7.8%	All 67 counties: 53 Zone II, 14 Zone III
25	Missouri	1,768	6.2	5.0%	Zone I statewide
26	Idaho	507	6.1	6.5%	Zone I statewide
27	Vermont	202	5.9	6.4%	Zone I statewide
28	New Hampshire	308	4.7	5.5%	Zone I statewide
29	Washington	1,605	4.7	5.3%	Zone I statewide
30	Virginia	1,548	4.1	4.4%	Zone II: 5 coastal cities
31	Ohio	2,127	4.0	3.3%	Zone I statewide
32	Nevada	502	3.7	5.2%	Zone I statewide
33	Kansas	467	3.6	4.0%	Zone I statewide
34	Iowa	507	3.5	3.2%	Zone I statewide
35	Pennsylvania	1,923	3.3	3.4%	Zone I statewide
36	Wisconsin	925	3.3	3.0%	Zone I statewide
37	Nebraska	279	3.2	2.6%	Zone I statewide
38	Colorado	826	3.1	3.3%	Zone I statewide
39	Minnesota	813	3.1	2.7%	Zone I statewide
40	California	3,065	2.1	3.4%	Zone I statewide
41	Utah	269	2.1	3.0%	Zone I statewide
42	Illinois	1,059	1.9	2.2%	Zone I statewide
43	New York	1,677	1.9	2.1%	Zone I statewide
44	Connecticut	163	1.0	0.7%	Zone I statewide
45	New Jersey	309	0.8	0.9%	Zone I statewide
46	Alaska	24	0.7	3.3%	Coastal regions, Zone III
47	Maryland	184	0.7	1.4%	Zone I statewide
48	Massachusetts	128	0.4	0.9%	Zone II: 5 counties
49	Rhode Island	14	0.3	0.8%	Zone I statewide
50	Hawaii	4	0.1	0.3%	Entire state, Zone III

Shipments: U.S. Census Bureau, Manufactured Housing Survey, annual shipments to states, 2025 (national total 102,738, including 316 with destination pending). Housing units and mobile or manufactured share: American Community Survey 2024 1-year, table B25024. Wind zones: 24 CFR 3280.305(c)(2); “Zone I statewide” means no county is listed in Zone II or III. Ranked by new homes per 10,000 housing units.

Buying a home that is already set

With an existing manufactured home, the mobile home foundation is something you inspect, not something you choose, and it can make or break the loan. Many older homes sit on dry-stacked blocks that were never certified, anchors that have rusted or straps that were never tightened, and a lender who requires a permanent foundation will send an engineer to look.

Joe Wooldridge, VP of Operations at Champion Builder Group, who has spent nearly 30 years in factory-built housing, puts the source of many complaints plainly: “When the problem is improper setup or unfinished site work, that’s a dealer or installation issue, not necessarily a factory construction issue.” On a resale, that setup is now yours, so look underneath before you make an offer.

1. Ask for the foundation certification. If the home was financed with FHA before, a certification may exist, and FHA can reuse it if nothing has changed.
2. Look under the skirting. Leaning or cracked piers, missing pads, standing water and rusted or loose straps all need fixing.
3. Check the floors and doors. Soft spots, slopes and doors that stick can point to settling piers or frost heave.
4. Find the data plate and HUD labels. They confirm the build date, the wind zone and that the home is a HUD-code home at all.
5. Price the fix before closing. Ask an installer and an engineer to quote re-leveling, new anchors or a certified foundation, and negotiate from those numbers.

How much a mobile home foundation costs

There is no reliable national price for a mobile home foundation, because the cost depends on the type, the home’s size, the soil, the frost depth and the wind zone. A basic pier-and-anchor setup is usually the least expensive, a perimeter wall or slab costs more, and a basement costs the most. An engineer’s certification is a separate line on top of the work.

Online price guides quote wide ranges that rarely say what they include. A better way to compare is to get two or three written bids on the same scope: the site prep and grading, the footings, the piers or wall, the anchoring, skirting and vents, and the certification your lender needs. If a bid looks far below the others, check which of those it leaves out.

Questions to ask the installer and the engineer

1. Which foundation type you recommend for this site, and whether it will be certified to HUD’s permanent foundation guide.
2. What frost depth and soil bearing capacity you are designing the footings for, and where those numbers come from.
3. Which wind zone and roof load zone the county is in, and whether they match the home’s data plate.
4. Whether you are licensed or certified in this state, and who inspects the installation.
5. What the price includes: grading, footings, piers or wall, anchors, skirting, vents, drainage and the engineer’s letter.
6. Whether the setup follows the manufacturer’s installation manual for this model, and whether you will leave a copy with me.
7. What happens to the warranty if the setup is wrong, and who fixes it.

If the lender needs a certification, bring the engineer in before the mobile home foundation is built, not after. Designing to the guide from the start is usually cheaper than fixing a finished foundation so it can pass.

Common questions about mobile home foundations

Where to look next

A mobile home foundation is one piece of a manufactured home project. These guides cover the land, the title and the loan.

Our rural property guides go state by state, and the Rural Property Buyer’s Field Guide covers due diligence on any rural parcel, from wells and septic to surveys and easements.