Glossary of Manufactured Housing Industry Terms

[A] [B] [C] [D] [E] [FG] [H] [I] [JKL]
[M] [NO] [P] [QR] [S] [T] [U] [V] [WXYZ]

-A-
-B-

Backlog

The unfilled order book that each plant strives to maintain. A healthy backlog permits the plant to effectively schedule releases for production. An excessive backlog creates delays in the construction and delivery of an order. Plants often increase their production rates when they have backlogs that would cause delivery dates to exceed four to five weeks fro the date of the order. Production will be stepped up until the plant reaches capacity. 

-C-            back to top

Chassis (also, steel frame; undercarriage)

The steel transportation device, with detachable hitch, axles and wheels. After functioning as a delivery platform, the chassis becomes part of the foundation support system of the home.

Close-up (verb)

To button-up, stitch or dry-in multiple sections of a manufactured home at its final placement location. (As a noun, "close-up" also means the temporary covering, usually consisting of plastic and boards, of the open sides of multi-section homes which protect them during transportation and storage.)

 

-D-            back to top

 

DAPIA (Design Approval Primary Inspection Agency)

Under the HUD Code, the DAPIA is the organization that reviews the manufacturer's complete drawing and engineering package for each home plan. If the engineering calculations demonstrate that the home will meet the HUD Code's performance standards, the DAPIA issues a plan approval to the manufacturer, which is the factory's authority to build and sell the home. This is the manufactured housing industry's equivalent to the local building department's plan-checking function.

Dormer

A projecting structure built out from a sloping roof, usually including one or more windows.

Drywall

Gypsum wallboard, often referred to by the brand name "Sheetrock" and sometimes mistakenly called "plasterboard," so named because it allows the builder to finish the wall surface without water, as required in previous plaster-and-lath wall finishing.

 

-E-             back to top

 

Eaves

The portion of a roof projecting past the exterior walls.

 

-FG-         back to top

 

Factory-built home

Any dwelling partially or completely built under the ideal conditions of a controlled factory environment. They can be modular homes, manufactured (HUD Code) homes, panelized homes, or precut (kit) homes. Although site-built homes may use factory-built components, such as trusses, windows and cabinets, these elements do not contribute enough to the finished structure to characterize it as a factory produced home.

Fastener plates

Braces of heavy sheet metal used in some manufactured homes to bolt finished walls to the subfloor frame.

Fiberglass

Flexible fragments of glass which can be spun or woven, and combined with other materials to make such products as insulating materials.

Floor

The manufactured housing industry's basic unit of production measurement. A floor is one single-section home, half of a double-section home, or one-third of a triple-section home. When manufacturers speak of building "eight a day," or shipping "130 last month," they are referring to floors. An older term, still used in parts of the industry, is "hitch."

Flooring (also, floor planning)

An inventory-financing technique common to the manufactured housing industry (as well as the auto, marine and small aircraft industries) that permits simple financing of a retailer's for-sale inventory of personal property merchandise.

 

-H-            back to top

 

HUD (United States Department of Housing and Urban Development)

HUD has jurisdiction over the manufactured housing industry, but not modular homes, whose construction is governed by the individual states.

HUD Code

The informal name for the National Manufactured Home Construction and Safety Standards.

-I-            back to top

I-Beam

A structural member of either wood or steel with a cross-sectional shape of the letter "I" for added rigidity.

Insulation

The protection of a structure from heat loss by filling wall, roof and floor voids with materials that retard heat flow.

IPIA (In-plant Primary Inspection Agency)

The HUD Code equivalent of the building inspector. The IPIA inspects each home in the factory while it is in production, to verify that the home is being constructed to the manufacturer's DAPIA plan approvals, the manufacturer's structural approvals and the manufacturer's Q/A manual.

-JKL-        back to top

Jigs

Stationary guides or templates upon which major subassemblies (subfloor frame, walls, roof) of manufactured homes are constructed prior to being fastened together.

-M-            back to top

Manufactured home

A factory-produced home constructed to the National Housing Construction and Safety Standards (HUD Code).

Manufactured Housing Institute (MHI)

MHI is the HUD Code industry's national trade association, located in Arlington, Virginia.

Mobile home

The term coined by Elmer Frey to describe his first ten-wide models, but soon adopted by the industry to describe homes manufactured from the mid-1950s through the mid-1970s. Strictly speaking, mobile homes are no longer produced, although casual terminology still refers to some manufactured homes as "mobile homes." Mobile homes were no longer built after June 1980, the date the U.S. Congress officially changed the term to "manufactured home." The term still applies, however, to pre-HUD-Code homes.

Modular home

A factory-produced home which is constructed in compliance with state or local building codes. These are fairly specialized structures and account for a small percentage of the total volume of factory-produced homes today.

Multi-section home

A manufactured home designed and constructed in two or more sections that are joined together at the the site to form a single structure. The most common multi-section homes are manufactured in two sections, but there are also "triple" and "quad" models consisting of three and four sections.

-NO-        back to top

National Manufactured Housing Construction and Safety Standards (HUD Code)

The national codes and standards established by Congress in 1974, which became effective for each manufactured home produced in the United States after June of 1976. (The HUD Code does not apply to modular homes, whose production is governed by individual states). The standards include the features of preemption and reciprocity. This is a set of performance standards, as opposed to local, state or modular codes, which are prescriptive standards.

-P-            back to top

Performance standards

Building codes that set out the way a structure must perform under natural conditions. Such standards mandate that the building must be able to withstand a certain wind velocity, a certain degree of shaking and vibration from earthquakes, a certain amount of weight on the roof, as well as resist the movement of a stated amount of heat energy through its exterior. Through engineering, these performance criteria are satisfied under the HUD Code program, and allow the manufacturer to avoid over-constructing the home. Further, the HUD Code requires performance engineering to assure the home's ability to travel at high speeds on the highways. Performance standards are in contrast to prescriptive standards.

Pitch

The degree of slope in a roofline, expressed in inches of vertical rise per foot (12 inches) of horizontal run. For example, a pitch of 4/12 means that for each horizontal foot the roof rises four inches.

Plan approval

A floor plan drawing carrying the manufacturer's DAPIA insignia, certifying that the model has been approved for production and meets the requirements of the National Manufactured Home Construction and Safety Standards. The plan approval of a manufactured home is similar to the site builder's plan-checked construction drawing.

Plywood

Wood sheeting consisting of three or more layers of veneer joined with glue. The alternate layers, or "plies," usually are arranged with grain running at right angles for added strength.

Preemption

A feature of the HUD Code which states that it may not be modified in any way by local or state building codes. The HUD Code preempts all other building codes with regard to manufactured housing.

Property, personal and real

Manufactured homes sold independently of the land on which they will be placed are classified as personal property. Homes that are permanently affixed to the land on which they are located through a foundation system are classified as real property.

-QR-        back to top

Quality Assurance (Q/A) Program and Q/A Manual

The HUD Code manufacturer's written document stating its procedures for designing, engineering, obtaining DAPIA plan approvals, and constructing, inspecting, testing, and certifying each home to be in compliance with the HUD Code. The Q/A Program and Manual must be approved and stamped by the DAPIA, which means the requirements of the HUD Code program.

Reciprocity

A feature of the HUD Code, meaning that it is applicable in each state. A HUD Code manufactured home built in Tennessee, for example, may be freely shipped to and installed at a homesite in Ohio. And similarly, a home built in Ohio can be placed on land in any other state.

Retailer

The traditional distribution point for the manufactured housing industry. Also known as "dealers," retailers are usually, but not always, independent of manufacturers. Retailers normally sell the home only, to be installed at the homebuyer's selected site. Use of the term "dealer" is discouraged by the industry.

Running gear

The removable hitches, axles and wheels under a HUD Code home. While the running gear is removed and recycled to the factory, the rest of the steel underframe (chassis) remains with the home and becomes an integral part of the foundation system.

-S-            back to top

Shingle

Materials of various sizes and types (often wood or fiberglass-asphalt composition) used to cover roofs and exterior sidewalls.

Single-wide home

A manufactured home consisting of one section. (The preferred industry term today is "single-section home"). Over half of all new manufactured home purchases are single-section models, the most popular of which are 16-feet wide.

Site-built home

A home which, except for some components like trusses, is mostly built on location.

Soffit

The underside of the eaves of a roof.

Span chart

A piering diagram provided by the manufacturer illustrating the required location and size of each point of support under the home.

Stud

Upright wall-framing member of wood or steel to which wall covering and exterior sheathing is applied.

Strapping

Lengths of sheet metal running up the exterior wall, over the roof and down the opposite wall to attach wall assemblies to the subfloor frame. In addition to reinforcing the structure, the strapping helps anchor the unit to its permanent homesite.

Structural approvals (also, "structurals")

A set of general construction techniques that are approved and stamped by the HUD Code home builder's DAPIA. The structural approvals cover all aspects of permitted materials and their assembly.

Subfloor

Plywood, OSB (oriented strand board), or particle board sheathing attached directly to the subfloor frame (joists or trusses) prior to installation of underlayment and finished floor.

Subfloor frame

A frame constructed of dimension lumber containing heating ducts and other utility lines, as well as insulating material. In  many manufactured homes, this is the first factory-built assembly of the unit.

Systems Tests

All the functional and mechanical systems in a HUD Code home must be tested in the plant prior to completion. Directed by the Q/A Manual, electric, water, drain, and gas systems must successfully endure rigid testing by applying electrical current and water and air pressure to simulate strenuous on-site service conditions. This testing is repeated after the home has been installed on its foundation at the homesite.

-T-            back to top

Tie-downs

Steel straps used to secure many manufactured homes to the homesite. Often, they are attached to the home where the strapping meets the chassis.

Tip-outs and pull-outs

Sections of a home (sometimes referred to as "expandos") that unfold or pull away from the main section, thus providing for an enlarged space.

Trusses

Pre-assembled, bow-shaped or triangular frames used in roof construction.

-U-            back to top

Underlayment

Plywood or other material, usually applied over a rough subfloor, to serve as a smooth surface for carpeting or flooring.

-V-            back to top

Vapor barrier

Plastic film, building paper, paint, or other material used to retard flow of moisture. Often applied after installation of insulating material to prevent moisture from entering the insulation and thus diminishing its effectiveness. Some insulation incorporates its own vapor barrier.

Vaulted ceiling

Arched, pitched or concave (barrel-shaped) ceiling design often incorporated to enhance the spaciousness of a room.

 

-WXYZ-    back to top

Home / Who We Are / Our Models / Plan A Home / FAQ / Glossary / Contact Us