Codes & standards for manufactured homes, mobile homes, doublewides, multiwides, & trailers.
This article assists mobile home, trialer, or doublewide owners and inspectors of those homes who need to find the appicable codes and standards for manufactured homes, multiwides, trailers or mobile homes.
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In the U.S. the HUD code (cited below) is a national preemptive building code that pertains to manufactured homes. As we explain at DEFINITIONS of MOBILE HOME, DOUBLEWIDE, MODULAR, PANELIZED CONSTRUCTION
Manufactured homes are those built entirely in a factory. They are then transported to a building site and installed.
A manufactured home is a single-family dwelling built according to the U.S. Department of Housing and Urban Development (HUD) Manufactured Home Construction and Safety Standards Act, which is a national, preemptive building code. - Washington State Government, http://www.lni.wa.gov/TradesLicensing/FAS/Mobile/ (2014)
A mobile home is a factory-built dwelling built prior to June 15, 1976, to standards other than the HUD Code, that were acceptable under applicable state codes in effect at the time of construction or introduction of the home into the state.
Manufactured Homes other countries such as Australia are regulated by different laws that we also provide here.
However the term "manufactured home" is used by different authoritis to include a variety of construction types as we list next. Manufactured homes include:
Modules are transported to the site and installed. See MODULAR HOME CONSTRUCTION for a detailed look at modern modular home construction.
Panels—a whole wall with windows, doors, wiring and outside siding—are transported to the site and assembled. See Panelized Construction for a detailed look at a 1950's panelized construction home that was war surplus (Fishkill NY).
Building materials are factory-cut to design specifications, transported to the site, and then assembled. Pre-cut homes include kit, dome, and log homes.
LOG HOME GUIDE - provides an example of pre-cut homes, how to inspect, diagnose, and repair problems on log houses; how to identify and determine the age of different types of log homes: traditional log homes, manufactured log homes, slab-sided log homes, and alternative log homes using concrete logs and fiberglass logs.
SEARS KIT HOME IDENTIFICATION provides the most famous example of pre-cut home construction.
This is the term used for factory-built homes produced prior to when the HUD Code went into effect.
A mobile home is a factory-built dwelling built prior to June 15, 1976, to standards other than the HUD Code [cited above] that were acceptable under applicable U.S. State Codes (or equivalent in other countries) in effect at the time of construction or introduction of the home into the state. E.g. U.S. Washington State WAC 296-150-M. - Washington State Government, http://www.lni.wa.gov/TradesLicensing/FAS/Mobile/ (2014)
See MOBILE HOMES, DOUBLEWIDES, TRAILERS for a detailed look at the wide range of quality and condition of these homes.
See MOBILE HOME ELECTRICAL DEFECTS for examples of differences in building & electrical code requirements depending on the type of construction.
The following is the opinion of the author and has not had a technical review by other industry experts. Various trailer, mobile home, and modular housing manufacturers may disagree with some of these views. Corrections and content suggestions are welcome.
Excerpts from U.S. HUD CFR › Title 24 › Subtitle B › Chapter XX › Part 3280 › Subpart A › Section 3280.2
Definitions in this subpart are those common to all subparts of the standard and are in addition to the definitions provided in individual parts. The definitions are as follows:
Approved, when used in connection with any material, appliance or construction, means complying with the requirements of the Department of Housing and Urban Development.
Bay window - a window assembly whose maximum horizontal projection is not more than two feet from the plane of an exterior wall and is elevated above the floor level of the home.
Certification label means the approved form of certification by the manufacturer that, under § 3280.8, is permanently affixed to each transportable section of each manufactured home manufactured for sale in the United States.
Dwelling unit means one or more habitable rooms which are designed to be occupied by one family with facilities for living, sleeping, cooking and eating.
Equipment includes materials, appliances, devices, fixtures, fittings or accessories both in the construction of, and in the fire safety, plumbing, heat-producing and electrical systems of manufactured homes.
Federal manufactured home construction and safety standard means a reasonable standard for the construction, design, and performance of a manufactured home which meets the needs of the public including the need for quality, durability, and safety.
Installations means all arrangements and methods of construction, as well as fire safety, plumbing, heat-producing and electrical systems used in manufactured homes.
Labeled means a label, symbol or other identifying mark of a nationally recognized testing laboratory, inspection agency, or other organization concerned with product evaluation that maintains periodic inspection of production of labeled equipment or materials, and by whose labeling is indicated compliance with nationally recognized standards or tests to determine suitable usage in a specified manner.
Length of a manufactured home means its largest overall length in the traveling mode, including cabinets and other projections which contain interior space. Length does not include bay windows, roof projections, overhangs, or eaves under which there is no interior space, nor does it include drawbars, couplings or hitches.
Listed or certified means included in a list published by a nationally recognized testing laboratory, inspection agency, or other organization concerned with product evaluation that maintains periodic inspection of production of listed equipment or materials, and whose listing states either that the equipment or material meets nationally recognized standards or has been tested and found suitable for use in a specified manner.
Manufacturer means any person engaged in manufacturing or assembling manufactured homes, including any person engaged in importing manufactured homes for resale.
Manufactured home means a structure, transportable in one or more sections, which in the traveling mode is 8 body feet or more in width or 40 body feet or more in length or which when erected on-site is 320 or more square feet, and which is built on a permanent chassis and designed to be used as a dwelling with or without a permanent foundation when connected to the required utilities, and includes the plumbing, heating, air-conditioning, and electrical systems contained in the structure. This term includes all structures that meet the above requirements except the size requirements and with respect to which the manufacturer voluntarily files a certification pursuant to § 3282.13 of this chapter and complies with the construction and safety standards set forth in this part 3280.
The term does not include any self-propelled recreational vehicle. Calculations used to determine the number of square feet in a structure will include the total of square feet for each transportable section comprising the completed structure and will be based on the structure's exterior dimensions measured at the largest horizontal projections when erected on site.
These dimensions will include all expandable rooms, cabinets, and other projections containing interior space, but do not include bay windows. Nothing in this definition should be interpreted to mean that a manufactured home necessarily meets the requirements of HUD's Minimum Property Standards (HUD Handbook 4900.1) or that it is automatically eligible for financing under 12 U.S.C. 1709(b).
Manufactured home construction means all activities relating to the assembly and manufacture of a manufactured home including, but not limited to, those relating to durability, quality and safety.
Manufactured home safety means the performance of a manufactured home in such a manner that the public is protected against any unreasonable risk of the occurrence of accidents due to the design or construction of such manufactured home, or any unreasonable risk of death or injury to the user or to the public if such accidents do occur.
Registered Engineer or Architect means a person licensed to practice engineering or architecture in a state and subject to all laws and limitations imposed by the state's Board of Engineering and Architecture Examiners and who is engaged in the professional practice of rendering service or creative work requiring education, training and experience in engineering sciences and the application of special knowledge of the mathematical, physical and engineering sciences in such professional or creative work as consultation, investigation, evaluation, planning or design and supervision of construction for the purpose of securing compliance with specifications and design for any such work.
Secretary means the Secretary of Housing and Urban Development, or an official of the Department delegated the authority of the Secretary with respect to title VI of Pub. L. 93-383.
State includes each of the several States, the District of Columbia, the Commonwealth of Puerto Rico, Guam, the Virgin Islands, the Canal Zone, and American Samoa.
Width of a manufactured home means its largest overall width in the traveling mode, including cabinets and other projections which contain interior space. Width does not include bay windows, roof projections, overhangs, or eaves under which there is no interior space.
What are the florida codes for a Manufactured Home steps. Can they be steal attached or wooded removable - Melissa 7/18/2012
Specific examples of unsafe steps and railings at mobile homes and manufactured homes can be found "
Because there are many trip and fall hazards that maybe present at stairs and railings, see our separate articles
STAIRS, RAILINGS, LANDINGS, RAMPS
CODES for STAIRS & RAILINGS. In addition to those specifications for safe steps and railings, most states require safe and securely-attached entry and exit stairs at both the primary entry to the home and also to a secondary safety or fire exit pathway from the home.
Some later model manufactured homes are provided with emergency egress windows (push out or pop out) but there should be at least two exit doors at opposite ends of the structure.
(July 29, 2016) Jimmy said:
When my 5th. wheel is parked and not leveled out by the jacks, the step height is 14.6" from the concrete pad to the top of the first step. I know there are codes for residential, but I was hoping there was something on 5th. wheels.
If your home is being uses as a residence, depending on where you live, residential stair codes would still apply;
Even if "codes don't apply" to your situation, safety applies as does the cost of injury or lawsuit;
Make your stairs safe by providing secure steps with reasaonable riser height - say in the 17.3" each range to make up the steps from the stair landing pad to the step that is attached to your 5th wheel home.
See STAIR RISER SPECIFICATIONS for details.
You may need handrails and guardrailings too, depending on the situation and the users of the steps.
(Aug 1, 2016) Jimmy said:
So what I think you are saying is, here s no code for any 5th wheel manufacturer on step rise, right ?
(Aug 1 2016) Mod said:
Not quite, Jimmy
There are certainly manufacturing standards for campers and trailers. But those are not building codes.
See NAICS Code 336214 Travel Trailer and Camper Manufacturing
Excerpt of description from SICCODE
this u.s. industry comprises establishments primarily engaged in one or more of the following:
(1) manufacturing travel trailers and campers designed to attach to motor vehicles
(2) manufacturing pickup coaches (i.e., campers) and caps (i.e., covers) for mounting on pickup trucks; and
(3) manufacturing automobile, utility and light-truck trailers. travel trailers do not have their own motor but are designed to be towed by a motor unit, such as an automobile or a light truck.
I do not know this code and did not find a downloadable copy; I'd be surprised if it addresses stair and handrail safety to the extent that you will find in buildign codes.
Are you working on litigation? It sounds that way.
In order to sort out the question of what are common construction practices and what is usually included or not with a manufactured home, we first need to get a couple of confusing terms straightened out.
You originally posted question about double-wide mobile home construction in our article on modular construction
See MODULAR HOME CONSTRUCTION) .
In a separate article we define modulars, factory built homes, comparing them with caravans, trailers, mobile homes, doublewides:
see DEFINITIONS of Mobile Home, Doublewide, Modular, Panelized Construction, where we give details about the differences in these types of construction.
Double-wides and mobile homes are not built using the same structural materials, codes, standards as modular homes. Details about double-wide homes and mobile homes are discussed separately beginning in the article starting at the top of this page:
See MOBILE HOMES, DOUBLEWIDES, TRAILERS.
Yes and no: some codes contain provisions for manufactured or mobile homes, while in other cases and locations those structures are governed by specific building codes.
A modular home is built using conventional 2x4 or 2x6 wood framing much like a stick built house, but it is constructed in several sections that are then trailered to a building site, set upon a conventional building foundation or slab, and fastened together there. The floor of each section is built strong enough to be placed on a temporary trailer for transport to the building site where the trailer chassis is removed prior to assembly of each section.
Building codes and standards for modulars are essentially the same as for a stick-built residential home. Even when the modular home is built in a different state from which it is to be assembled, the home must comply with state building codes.
Also see MOBILE HOME ELECTRICAL DEFECTS
A double-wide or mobile home or trailer (also called house trailers or "static caravans") is typically built to different building standards than a conventional stick-built house or modular built house. These homes are completely assembled in a factory and trailered to a site where they are parked.
The structure includes a permanently-attached trailer chassis, axle, wheels, trailer hitch that are used to deliver the home and can (in concept) be used to move it later.
Unlike modular homes whose constructions are regulated by state and local building codes, mobile homes, double-wides and trailers, are regulated by the U.S. Department of Housing and Urban Development (HUD), via the Federal National Mfd. Housing Construction and Safety Standards Act of 1974.
This national regulation has allowed many manufacturers to distribute nationwide because they are immune to the jurisdiction of local building authorities. There are, however, windzones adopted by HUD that home builders must follow. Depending on where a mobile home is located, these wind zone regulations can require special anchoring or tie downs to reduce the chances of the home being overturned in a storm.
Based on the description in your posted comment/question and your email, you are describing a double-wide mobile home.
Where would the section 184 Red Tag be located on a 1983-West single wide? - Suzanne
(Apr 16, 2014) Sharon said: how do I find the mobile home manufacturer information?
How can I find the name of the manufacturer and model, and possibly a serial number of a 1971 manufactured home? The title says Make: MALB, Body: HS. The home now has vinyl siding so any label is concealed.
Sharon, in this article at MOBILE / MANUFACTURED HOME LABELS we list some locations where you might find the data tag on your mobile home - that's where the manufacturer should be identified. On a home as old as yours there may be no tag. At that point I'd start asking my neighbors who have similar-aged homes.
Section 184 refers to manufactured home financing assistance available in the United States from HUD. A red tag indicating that the home qualifies for financing under Section 184 is installed on homes that are eligible. If the Section 184 red tag is missing, the house is not eligible for Section 184 financing. Only manufactured homes built after June 15, 1976 qualify. The tag is mounted outside on the rear of the unit.
This HUD financing pertains to manufactured homes sometimes referred to as "doublewides". So even though your 1983 single wide is newer than the 1976 cutoff year, it may not qualify as qualifying housing by the HUD rules, and it won't bear the RED TAG you are asking about.
Other HUD Section 184 Indian Home Loan Guarantee Program rules that determine if a home qualifies for 184 financing (and thus will bear a red tag) include: 
Examples of mobile home labels are found at MOBILE / MANUFACTURED HOME LABELS.
More about relevant mobile home codes, as we expand our local inspection policies:
Where not preempted by the federal code (i.e., things outside of the manufactured home or in mobile homes manufactured prior o 1976), you might want to consult the NFPA 501 Standard on Manufactured Housing, 2013 edition, and NFPA 501A, Standard for Fire Safety Criteria for Manufactured Home Installations, Sites, and Communities, 2013 edition, are both referenced in NFPA 1 (2015). Of course, not all jurisdictions use NFPA 1, preferring International Fire Code or their own home brew of codes.
Furthermore, for those enacting NFPA 1: "New manufactured housing shall comply with Section 20.11 and NFPA 501, Standard on Manufactured Housing." NFPA 1 (2015) National Fire Code, section 20.11.5: Occupancy Fire Safety; One- and Two-Family Dwellings and Manufactured Housing.
"Manufactured Home Sites. The fire safety requirements for the installation of manufactured homes and manufactured home sites, including accessory buildings, structures, and communities,
shall comply with NFPA 501A, Standard for Fire Safety Criteria for Manufactured Home Installations, Sites, and Communities." Ibid., 27.2.
Where the code says "shall comply" it means everyone has to do it, unless they get a proper waiver from the fire marshal, i.e., show that their alternative provides adequate or equivalent safety as would an installation in strict compliance with the code.
FWIW, NFPA 501 has its own labeling requirement showing certification of compliance with NFPA 501 on a permanent plate mounted on the taillight end of each transportable (mobile) unit, located one foot up from the bottom and one foot in from the "road" side. - NHFireBear is a fire inspector and a frequent contributor to InspectApedia.com - Ed.
This article references "Codes and Standards Act" for manufactured homes at 24 CFR Parts 0-199, 5/1/2001.
This manufactured-home standard contains 10 subparts (listed below) pertaining to General (data plate and certification contents and locations), Plans (dimensions, exits, etc), Fire Safety, Body and Frame, Testing, Thermal Protection, Heating/Cooling and venting systems, Electrical, and Transportation (axles, springs, drawbar).
It's about 90 pages of regulations. Part 3282 discusses pre-emption of state laws, among other things, and requires a new unit to be delivered with a "consumer manual" containing required information about the unit. NH FireBear
The actual Manufactured Home Construction and Safety Standards begin in Subtitle B - REGULATIONS Relating to Housing and Urban Development (Continued) [PDF] at Part 3280, in Vol.5, [That is on page 107 of the PDF given above - Ed.] - original source www.gpo.gov/fdsys/pkg/CFR-2001-title24-vol5/pdf/CFR-2001-title24-vol5-subtitleB.pdf.
There (on start on p. 107 or use your PDF reader to search for "3280") you will find
Thank you once again NHFireBear. For the convenience of readers I have excerpted the portions of the HUD document pertaining to manufactured housing and have included a live link to the document in the article above.
(Apr 9, 2015) NHFireBear said:
You guys are AWESOME! Thanks for cheerfully accepting my suggestions! I know many readers couldn't care less where the rules came from, but others may be curious about the source materials. I came across these materials while trying to help an owner dealing with an inspection triggered by a "housing assistance" application by a renter.
(August 1 2016) NH FireBear said:
... the article [above] does mention "local building codes" (pertaining to MODULAR home, for some reason not relevant to this article), but leaves questions about what other codes may apply, under a section on questions, such as "what Florida codes apply to manufactured home steps" and "What building codes regulate mobile homes & doublewide homes?"
However, it has recently come to my attention the the ICC's International Residential Code (IRC), which is adopted as part of the building code in many states, includes a specific appendix (E) for "Manufactured Homes Used as Dwellings".
The IRC lays out LOCAL CODE applicability to permits and inspections for "Construction, alteration and repair of any foundation system... building services equipment which is necessary for connecting manufactured homes to water, fuel or power supplies and sewage systems, as well as alterations, additions or repairs to existing manufactured homes..." It also mentions that any "auxiliary structures" associated with a mobile/mfd home installation are covered by "applicable local codes", and not preempted by the federal code on the construction of the dwelling itself.
In other words, the state/county/municipality may have their own codes (e.g., the IRC or local equivalents), which do apply to everything OUTSIDE of the manufactured home (which is pre-empted by federal code), as well as installation and any later modifications.
Similarly, it is quite possible that state/local FIRE CODES (including life-safety codes) will apply to inherently unsafe installations, such as pre-1976 mobile homes that lack adequate escape windows or smoke detectors, among other things, especially under any specific programs requiring fire inspections/compliance.
- by private email from NHFirebear 2016/08/01
The ICC has free, limited, live, online access to some of the latest codes, but I couldn't find the free link for IRC immediately.
Thanks NH Firebear,
It's a serious problem that shows up at InspectApedia as some reader questions about code compliance, particularly because there is a high correlation between people who place mobile homes on sites AND people who put up modulars and real ignorance of good construction practices, codes, and standards.
Factory built housing is particularly appealing to that class of builders who are not really builders but rather desk-men (and women) who order homes and get them put-up. Often, perhaps usually, because the builder is relying on the assured-code-compliance of the principal structure, and because they are not themselves educated builders but more they are financial people and order-takers or promoters, there is nobody on-site making sure that other site work and features are correct and safe.
I have seen in modular construction foundation catastrophes, incoming electrical fiascos, incoming water and outgoing sewage snafus, house-to-foundation shape mis-match, and even a house roll-over and another foundation collapse.
Even when the factory insists on sending their own trained site crew to install a home the surrounding work may be incompetent.
Similarly in mobile home set-up, complete failure to install proper support, piers, tie-downs. Mobile homes are in some situations more egregious as the buyers tend to be lower-income with less resources to make things right or even to check that the siting and site infrastructure are safe.
SEPTIC & CESSPOOL SAFETY has an example with my friend Steve Vermilye showing a collapsing DIY concrete block access to an open septic tank at a large mobile home facility for farm workers at a famous and expensive NY Pate production facility that we inspected for the farm workers union and for lawyers.
This was just one of many dangerous situations. Electrical was similar.
While 2 or even 3 layers of asphalt shingles may be permitted on conventional site-built or "stick built" (and probably modular) homes, manufactured homes - assuming we're using the euphamism for mobile home, doublewide, trailer - may be permitted only one layer of shingles at a time on the roof.
Where does this one-layer of shingles on mobile home roofs originate?
Where this one-layer rule is true and appropriate is probably on older mobile / manufactured homes or even new ones if the home was not framed using framing members of the same dimension and strength as a conventional stick built or modular home (typically 2x6, 2x8 or larger rafter or truss roofs of sufficient strength to carry the weight that can, spread over the roof surface, be a ton or more).
For conventional-framed homes regulated by model codes like the IRC figure that two layers is commonly permitted and in some jurisdictions up to 3 layers of asphalt shingle roofing on those structures.
Most experts we consulted and several insurance companies all insist that only one layer of asphalt roof shingles is permitted on manufactured homes, mobile homes, doublewides, trailers, presuming that those structures were built with original framing not intended for the added weight of additional layers of asphalt shingle roofing that can weigh about 100 lbs / square or an additional ton or more of dead load on the structure.
It's interesting that some HUD and FHA documents imply that up to 3 layers of roofing may be permitted, while not always making clear just which building types are being discussed:
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