Glossary of Terms

ABS

Acrylonitrile butadiene styrene. Plastic material used in the fabrication of footers (pads) under manufactured homes and stabilizer plates for auguring ground anchors.

Appraisal

A report made by a qualified person setting forth an opinion or estimate of value of the property. The term also refers to the process by which this estimate is obtained often showing the basis for the appraiser's estimate.

Assessor's Parcel Number—APN

A number found in real property records. This number is assigned by a county to identify and track a particular piece of property. This website can provide individual information on counties in California.

Chassis

The steel trailer that carries the weight of the manufactured home. The entire transportation system includes the following subsystems: drawbar and coupling mechanism, frame, running gear assembly, and lights.

Chattel

Personal Property. Manufactured homes are unique in that they can either be classified as personal property (like a car) or real property like real estate depending on the foundation and the local/state installation requirements. In California, manufactured homes remain chattel until a foundation is installed in compliance with Section 18551 of the California Health and Safety Code and a 433A is recorded with the local county recorder's office.

CMHI

California Manufactured Housing Institute—A professional organization that advances information and the improvement of the manufactured housing and factory built housing industry.

Codes: Local and State

As opposed to the HUD code, which is preemptive of local codes and creates uniformity of manufactured home construction across state lines, foundation systems are typically subject to state or local building codes. So, while the homes themselves may enjoy consistency of design and construction, foundation plans are subject to review by the local code enforcement authorities. All of the retrofit foundation systems must be tailored to the site conditions. If local building department approval is required, the use of a local engineer to prepare plans for submission is prudent and may be required for HUD/FHA-insured financing. Proprietary systems almost always carry engineering approvals, but some building departments may not approve their design concepts.

Consumer Complaints

HUD has entered into cooperative agreements with 38 State governments to respond to consumer complaints about the performance of manufactured homes. These state governments each designate a State Administrative Agency (SAA). If you have any complaints about the performance of your manufactured home that have not been resolved by the retailer or by the manufacturer, you should first contact the SAA where you live.

Contractors State License Board (CSLB)

The licensing agency that oversees contractors. Contractors that specialize in manufactured homes should have a C-47 specialty classification indicating that they specialize in all phase of manufactured housing construction, including understructures.

Crawl space

A crawl space incorporates full perimeter wall support together with internal, independent support points; the space itself is not habitable.

DAPIA—Design Approval Primary Inspection Agency

These are third-party independent agencies that approve manufactured home engineering and designs for compliance with the Federal Manufactured Home Construction and Safety Standards.

Dead loads

The weight of all materials of construction incorporated into the building, including but not limited to walls, floors, roofs, ceilings, stairways, built-in partitions, finishes, cladding, and other similarly incorporated architectural and structural items, and fixed service equipment.

Engineer

A registered structural engineer. In the case of proprietary foundation systems with an SPA (Standard Plan Approval), each one has an engineer of record. In the case of FHA loans, an engineer is usually required to certify the foundation.

Engineer's Certification

A letter issued by a structural engineer certifying the acceptability of a foundation system, generally to meet the HUD Publication, Permanent Foundation Guide For Manufactured Homes dated 1996. Most lenders require that this is wet-stamped, indicating his license number and the date he places the stamp.

Earthquake Resistant Bracing Systems or ERBS.

Proprietary systems that have been rated to resist seismic events. See Seismic Load Resistance.

Expansive soils

Soils that change volume significantly as their moisture content changes.

Factory Built aka Modular Home

A dwelling unit fabricated in an off-site manufacturing facility for installation or assembly at the building site, bearing a label certifying that it is constructed in compliance with local building codes. Unlike manufactured homes that are built to one national preemptive code, factory-built homes are constructed to comply with the local building prescribed codes.

FEMA

Federal Emergency Management Agency.

FHA

Federal Housing Administration within the U.S. Department of Housing and Urban Development.

FHA Mortgage

To qualify for FHA insured loans:

• Must have a floor area of not less than 400 square feet.
• Must be classified and subject to taxation as real estate
• Must be built on and remains on a permanent chassis.
• Must be above the 100 year return frequency flood elevation.
• Must be built after June 15, 1976
• The foundation system must meet the guidelines published in the Permanent Foundations Guide for Manufactured Housing, dated September 1996. A certification attesting to compliance must be obtained from a licensed professional engineer.
• The manufactured home must not have been installed or occupied previously at any other site or location.
• Additions or structural modifications must not put the home at risk.

FHA Number

The loan number assigned to a particular borrower and particular property.

Flashing

Sheet metal or other material used to seal around penetrations to resist moisture intrusion.

Flood plain or flood-prone area

Any land area susceptible to being inundated by water from any source. There are some retrofit foundation systems that are suitable for use in flood plain areas when FEMA's performance criteria are used.

Footers (see Pads)

The parts of a foundation system that actually transmit the weight of the building to the ground.

Form 433A

Notice of Manufactured Home (Mobilehome) or Commercial Modular Installation on a Foundation System. This is the Department of Housing and Community Development (HCD) Form that specifies that the home meets California Standards of an upgraded foundation system, effectively attaching the home and land, conjoining them as real property. This document is in accordance with California Health and Safety Code Section 18551 (a)

Form 433C

Notice of Manufactured Home (Mobilehome) Conversion To A Fixture Improvement To Real Property in accordance with California Health and Safety Code, Section 18555. Because of the wording on this form and the use of the term "affixture", many escrow and title companies have mistakenly believed that this form effectively turned the manufactured home into real property. Instead this designates the home for assessment on real property, but the home remains chattel or personal property. Most lenders will no longer accept the 433C since their security interest is

Foundation

The term "foundation" means all components of the support and anchoring system (that might include such features as piers, footings, slabs, walls, ties, anchoring equipment, ground anchors, or any other material or equipment) that supports a home and secures it to the ground.

Freddie Mac Manufactured Home Lending Requirments

• Built on a permanent chassis in compliance with HUD.
• Must have a HUD certification label or data plate.
• Must be affixed and attached to a permanent foundation system and the land must be owned by the borrower (unless located in a condominium project)
• Must be permanently connected to sewer or other utilities.
• Must be at least 12 feet wide and have a minimum of 600 square feet.
• Must be built after June 15, 1976.
• The dwelling unit must be legally classified as real property.
• The wheels and axles must be removed.
• Must have a licensed engineer or the local building jurisdictions approve any structural modifications.

Grade

The finished ground level adjoining the building at all exterior walls.

HCD

Department of Housing and Community Development—the regulating agency that oversees manufactured housing installations, codes, park regulations and park residency laws.

HUD

U.S. Department of Housing and Urban Development.

HUD-Code home

A home meeting the U.S. Department of Housing and Urban Development's standards for new manufactured homes, known as the Manufactured Home Construction and Safety Standards. HUD has regulated the design and construction of manufactured homes, formerly known as mobilehomes since June 15, 1976 to a specifric performance code. This is called a preemptive code because it preempts all local building codes for these single-family dwellings. The Federal program includes the monitoring of third parties involved in the design review and inspection process, but excludes the actual siting of the homes. Some states inspect every installation, while others transfer the responsibility to local jurisdictions or not at all. While there are some lenders that will finance a mobilehome built prior to June 15, 1976, homes financed with an FHA mortgage must be HUD Homes.

HUD Label/Tag

The tag is a 2x4" aluminum insignia plate that is attached to the lower rear corner of each transportable unit. The first three alpha characters letters identify the inspection agency (IPIA) that inspected the home while it was under construction. A series of numbers follow the IPIA. While the numbers or generally sequential on multiple units, this is not a requirement.

HUD Tags (Missing)

HUD does not reissue tags for manufactured homes. However, effective January 2007, you may requrest letters of label verification from the Institute for Building Tehncology and Safety (IBTS).

IBTS (Institute for Building Technology and Safety)

IBTS reviews a portion of the designs that have been approved by third party design agencies, as well as assisting HUD in evaluating the performance of Design Approval Primary Inspection Agencies (DAPIAs). The DAPIAs approve manufactured home designs for compliance with the Federal Manufactured Home Construction and Safety Standards. IBTS visits the headquarters of these agencies to perform periodic audits and to make recommendations to HUD on his findings. They also maintain an imaging system to input and retrieve hundreds of thousands of design documents received annually. In addition, the IBTS maintains a system to input and retrieve technical correspondence on the standards and their enforcement. When HUD tags are missing, IBTS can often provide verification of the provenance of the manufactured home so it can qualify for FHA financing.

I-Beam or C-Beam

A steel joist or girder with short flanges and a cross section formed like the letter I or C. The beams are an integral part of the manufactured home chassis and it is the location of where the support stanchions are placed.

IPIA (In-house Primary Inspection Agency)

The third party agency that inspects each manufactured home within the factory setting to make sure the construction standards comply with the national code. Click here to obtain a list of inspection agencies.

Insiginia/Label

HCD issued insignias until June 14, 1976. HUD began issuing labels on June 15, 1976. Both confirm that the manufactured home was constructed to standards in effect at the time it was built.

Laser Level

On existing homes, a laser level is usually counter-indicated because they only work where there is a continuous line of sight. Generally existing piers, plumbing lines, ducting debris and tools are in the way. All leveling should be done on the chassis, not on the floor above.

Live loads

Those loads produced by the use and occupancy of the building or other structure and not including construction loads or environmental loads such as wind load, snow load, rain load, earthquake load, flood load, or dead load.

Loan Processor

The individual that oversees all aspects of the loan qualification process, often acting as a liaison between the borrower and the underwriter. The loan processor will gather and analyze such information as the Preliminary Title Report, the appraisal, the credit worthiness of the borrower, the type of foundation on the manufactured home and other pertinent facts.

Manufactured Home (Formerly Mobilehome)

A dwelling unit fabricated in an off-site manufacturing facility for installation or assembly at the building site, bearing a label certifying it is constructed in compliance with the federal Manufactured home Construction and Safety Standards making it a HUD home.

Marriage or mating wall

The joint between two sections of a double-section or triple-section home.

Mobile Home

A transportable, factory-constructed home, designed to be used as a year round residential dwelling and built prior to the enactment of the federal Manufactured Housing Construction and Safety Standards Act of 1974, which became effective June 15, 1976.

Modular (See Factory Built aka Modular Home)

Moisture Barrier

A technique for minimizing moisture accumulation under the home is to place a continuous polyethylene sheet of at least 6-mil thickness on the ground below the home. The barrier blocks moisture in the ground from entering the crawl space.

Outrigger

An integral part of the chassis, the outrigger projects laterally from the longitudinal frame members. On many manufactured homes, the outriggers are generally placed about 8' on center and give strength to the exterior walls.

Pads

The footer on the ground is designed to spread the load from a pier over a larger area, thereby providing a more stable base. The square pad footers may be concrete, either poured in place or precast, preservative-treated wood, acrylonitrile butadiene styrene (ABS), or other materials approved by the local building authority. The spacing of the piers and the allowable bearing capacity of the soil determine the size of the footer or pad. The piers are typically spaced from 5 to 10 ft apart depending on home design, local soil characteristics, and roof snow load. However, in certain conditions closer spacings allow for better adjustability in order to tweak doors or reduce floor vibration.

Park Model

A park model 14' or narrower and 40' or shorter and less than 400 square feet. It is not built to either HUD building corde or to any site building code. Park models are not modular homes and they are not manufactured homes---and they are not trailers. They are a breed of their own. Although they are designed for being towed from the factory to the site, they are typically never moved again. While they can be permanently installed on land belonging to the same owner, their big draw back is that they cannot be easily financed because they are not eligible for Frannie Mae, Freddie Mac or FHA type of loans. Either this type of loan will have to receive private financing or it will never be able to be sold to the secondary market. Although they can be financed and taxed as real property, it is their lack of a residential building cede that makes them ineligible for typical financing.

Penetrometer

An instrument for measuring firmness or consistency (as of soil). The allowable bearing capacity of the soil is a measure of its strength and ability to carry the weight of the pier without settling or compressing. On new sets, pads for piers should be set on compacted or undisturbed (not loosened by digging or plowing) soil. Organic or loose matter, such as weeds, trash, and other objects, must be cleared away, and then the area for the pad scraped until solid, undisturbed soil is exposed. If this is not done, uneven settlement can occur.

Permanent foundation

The U.S. Department of Housing and Urban Development (HUD) defines permanent foundation systems in its Manufactured Home Procedural and Enforcement Regulations as follows:

"(ii) A site-built permanent foundation is a system of supports, including piers, either partially or entirely below grade which is

• (A) Capable of transferring all design loads imposed by or upon the structure into soil or bedrock without failure,
• (B) Placed at an adequate depth below grade to prevent frost damage, and
• (C) Constructed of concrete, metal, treated lumber or wood, or grouted masonry."

Pier Systems

The pier and pad system has long been the common and accepted manufactured home support system. It adapts easily to local site conditions, does not require a great deal of dimensional precision, and goes into place quickly. In the most frequently used configuration, piers are installed under the main beams of the home sections, under the mating line of multi-section homes and at other points designated by the home manufacturer. Perimeter piers or blocks may also be a part of the home's support system. The most common pier types are steel jack stands or hollow core concrete masonry blocks with open cells placed vertically and stacked one on top of the other to the required height. These can be single stacks of blocks or double stacks, laid in an interlocking configuration. Concrete block piers more than 36 in. high should be configured as double block piers. Piers more than 80 inches high should be designed by a registered engineer. Another pier type is the pyramid-shaped open frame, steel type with a support plate on top of an adjustable rod at the apex. The steel pyramids come in several heights and support prescribed/rated load capacities based on manufacturer's testing. The pier height and building weight dictate the allowable spacing between the piers.

Piers

Short columns of masonry or steel that provide support between the footing and the main beam.

Pit Set, Subterranean Set, Crawl Space Foundation

The pit set/crawl space foundation system described here has two main distinguishing characteristics it incorporates full perimeter wall support together with internal, independent support points; and the space itself is not habitable. Within that very broad definition, there are many styles, designs, and ways to build crawl space foundation systems. This is popular because the low profile appearance resembles a "site" built home on slab foundation. In the best case scenario, the perimeter wall rests on an excavated footer. The wall itself maybe constructed of one or more conventional building materials (such as poured concrete, concrete block, or treated wood) and the entire perimeter of the manufactured home floor bears directly upon this wall. The chassis also is fully supported, but with relatively economical piers. The manufacturer-designated ridge beam support points are carried by economical piers or posts. The home's resistance to horizontal or uplift forces is achieved through attachment of the floor joists to the exterior foundation wall. Ideally, the structural walls form a barrier to the entry of water underneath the home and act as a short retaining wall. However, in developments where there is terracing or hydrostatic pressure, it is common for water to percolate under the home and these types of foundations because they are historically poorly ventilated actually trap water underneath. In some of the older developments, the low profile appearance was achieved by digging a whole for all the pier and pad components but there is no supporting perimeter wall. In those cases, only the interior piers support the home. If water is a factor, ongoing review of these understructures is necessary to maintain proper support. The perimeter load-bearing enclosure wall support system provides excellent gravity load resistance. The perimeter wall carries much of the roof load directly to the earth. The chassis main beams and piers carry only the interior floor loads. The perimeter enclosure wall supports the full perimeter of the home. Further, homes set in "low profile" offer less wall exposure to high winds, thus reducing the loads required to be resisted by the connections. The perimeter load-bearing enclosure wall support system combined with a deep stemwall provides adequate seismic load resistance. The structural connection of the home to the perimeter foundation wall can be designed to effectively transfer the forces to the earth around the foundation.

Psf

Pounds per square foot.

Psi

Pounds per square inch.

Real Property Foundation

The manufactured home is the only type of residential dwelling intended to be used as either personal or "real property." Manufacturers often establish a special set of conditions for foundation systems intended for use with homes financed as real property with a mortgage or deed of trust. The techniques for supporting homes financed as either real or personal property are intended to result in properly engineered and reliable foundation systems. In all cases, real or personal property status is determined by state or local laws that may or may not reference foundation type. Similarly, eligibility for conventional long-term financing is determined by underwriting standards that may or may not reference the foundation type or real versus personal property status.

Retrofit

To upgrade an existing home's understructure by installing a state or federally certified tie-down, earthquake resistant bracing or foundation system to either satisfy jurisdictional codes or insurance and lending requirements.

Reverse Mortgage Loan

In a reverse mortgage loan, the borrower does not need to provide verification of income to procure a loan. The only determining factor for loan qualification is the assessed value of the home and the age of the borrower. In a reverse mortgage transaction, every foundation of the manufactured home must be inspected and certified by an engineer to specify that it meets the guidelines of the Permanent Foundation Guide For Manufactured Homes dated 1996.

Rim joist

The outermost joist around the perimeter of the floor framing.

Shear wall

A general term for walls that are designed and constructed to resist racking from seismic and wind forces by use of masonry, concrete, cold-formed steel or wood framing.

Seismic Load Resistance

Since the HUD standards have no provisions for seismic resistance design, almost all manufactured housing, (and, therefore, most pier and pad installations) is not designed specifically to withstand seismic loads. Calculations show, however, that a manufactured home capable of resisting the HUD code wind forces will slightly exceed the requirements meeting for the highest seismic forces in the model building codes. Some manufacturers of proprietary systems have Standard Plan Approvals for Earthquake Resistant Bracing Systems or ERBS.

Skirting

Weather-resistant framing and sheeting used to enclose the crawl space of a manufactured home.

Slope

The fall (pitch) of a line of pipe in reference to a horizontal plane. In drainage, the slope is expressed as the fall in units vertical per units horizontal (percent) for a length of pipe.

SPA

Standard Plan Approval—Qualifying proprietary retrofit foundation systems have an SPA number that can be presented to the governing licensing authority, reducing the difficulty of pulling a permit.

UBC

Uniform Building Code

Underwriter

In banking the term is used for the process of analyzing the credit worthiness of the property or borrower or both, based on credit history, appraisal of home, or other. The underwriter is often a different entity than the mortgage banker.

VA

Veteran's Administration

Vapor Barrier

The underbelly material that covers, holds up and protects the insulation under the subfloor. An intact vapor barrier prevents nesting of rodents in the insulation as well as minimizes the impact of moisture build-up in the sublfoor and wall systems.

Vent

Openings in the skirting to provide underfloor ventilation.

Ventilation

The primary purpose of crawl space ventilation is to minimize the accumulation of moisture under the home. Excessive moisture accumulation under any home can create an ideal environment for moisture seepage into the home itself. The general standard is one foot of ventilation for every 150 square feet of underfloor area.

Wet Stamp

A wet stamp indicates an original signature. On plot plans, building jurisdictions often request wet stamp signatures of homeowner or homeowner's agent certifying authorization or lot lines. On engineering certification letters. underwriters generally want an original copy of the engineer's actual "stamp."

WMA

Western Manufactured Housing Association, a professional organization that works for the advancement and dissemination of information about the manufactured housing and factory-built housing industry.