plus 50 sq. ft. for each person in excess of two.

(c) Every room designed for sleeping purposes shall have accessible clothes hanging space with a minimum inside depth of 22 inches and shall be equipped with a rod and shelf.

§ 280.111 Minimum room dimension.

The gross floor area required by $ 280.110(a) and (b) shall have no clear horizontal dimension less than 5 feet except as permitted by § 280.102(a). § 280.112 Toilet compartments.

Each toilet compartment shall be a minimum of 30 inches in width, except, when the toilet is located adjacent to the short dimension of the tub. the distance from the tub to the center line of the toilet shall not be less than 12 inches. At least 21 inches of clear space shall be provided in front of each toilet § 280.113

Hallways.

Hallways shall have a minimum horizontal dimension of 28 inches measured from the interior finished surface to the interior finished surface of the opposite wall. When appliances are installed in a laundry area. the measurement shall be from the front of the appliance to the opposite finished interior surface. When appliances are not installed and a laundry area is provided, the area shall have a minimum clear depth of 27 inches in addition to the 28 inches required for passage. In addition, a notice of the available clearance for washer/dryer units shall be posted in the laundry area. Minor protrusions into the minimum hallway width by doorknobs, trim, smoke detectors or light fixtures are permitted. § 280.114 Glass and glazed openings.

(a) Windows and sliding glass doors. All windows and sliding glass doors shall meet the requirements of § 280.403 the "Standard for Windows and Sliding Glass Doors Used in Mobile Homes".

(b) Safety glazing. Glazing in all entrance or exit doors, sliding glass door units (fixed or moving sections), unframed glass doors, unbacked mirrored wardrobe doors (i.e. mirrors not secured to a backing capable of being the door itself), shower and bathtub enclosures and surrounds to a height of 6 feet above the bathroom floor level, storm doors or combination doors, and in panels located within 12 inches on either side of exit or entrance doors shall be of a safety

(a) The following definitions are applicable to Subpart C only:

(1) "Flame Spread" means the propagation of flame over a surface.

(2) "Interior finish" means the surface material of walls, fixed or movable partitions, ceilings and other exposed interior surfaces affixed to the mobile home structure including any material such as paint or wallpaper and the substrate to which they are applied. Interior finish does not include windows and doors or their frames, skylight, trim, moldings, decorations or furnishing which are not affixed to the mobile home structure. (3) "Single Station Alarm Device" an assembly incorporating the smoke detector sensor, the electrical control equipment requirement, and the alarm-sounding device in one unit.

means

(4) "Smoke Detector" means wall mounted detector of the ionization chamber or photoelectric type which detects visible or invisible particles of combustion and operates from the 120 V AC source of electrical power supply. § 280.203

Flame spread limitations and fire protective requirements.

(a) Flame spread limitations. The surface flame spread rating of interior finish materials shall not exceed the followIng when tested by Standard Method of Test for Surface Burning Characteristics of Building Materials, ASTM E84. The surface flame spread rating of interior finish materials required by § 280.203(a) (4) and (6) may be established using the Surface Flammability of Materials Using a Radiant Heat Energy Source, ASTM E162. Testing shall be by laboratories acceptable to the Secretary.

(1) The interior finish of all walls and partitions shall not have a flame spread rating exceeding 200 except as otherwise

specified herein. The flame spread limitation shall not apply to; molding, trim, windows, doors or series of doors not exceeding 4 feet in width, and permanently attached decorative items such as pictures or accent panels constituting not more than 10 percent of the aggregate wall surface in any room or space nor more than 32 square feet in surface area whichever is less.

(2) All ceiling interior finish shall not have a flame spread rating exceeding 200, excluding molding and trim 2 inches or less in width.

(3) Furnace and water heater spaces shail be enclosed by walls, ceiling and doors having an interior finish with a flame spread rating not exceeding 25.

(4) Combustible kitchen cabinet doors countertops, exposed bottoms and end panels shall not exceed a flame spread rating of 200. Cabinet rails, stiles, mullions and toe strips are exempted.

(5) Exposed interior finishes adjacent to the cooking range shall not have a flame spread rating exceeding 50. Adjacent surfaces are the exposed vertical surfaces between the range top height and the overhead cabinets and/or ceiling and within 6 horizontal inches of the cooking range.

(6) Finish surfaces of plastic bath tubs, shower units and tub or shower doors shall not exceed a flame spread rating of 200.

(b) Fire protective requirements. The interior surfaces of walls and ceilings encasing furnace and water heater enclosures (including combustible doors for either interior or exterior access to the enclosures) and the exposed wall adjacent to the cooking range as referenced in § 280.203(a) (5) shall be protected by 5/16'' gypsum board or material having equivalent fire protective properties. At furnace and water heater spaces, all openings for pipes and vents shall be tight-fitted or fire-stopped.

[40 FR 58752, Dec. 18, 1975, as amended at 42 FR 961, Jan. 4, 1977]

§ 280.204 Kitchen cabinet protection.

(a) The bottom and sides of combustible kitchen cabinets over cooking ranges including a space of 6 inches from the side of the cooking range shall be protected with at least 4 inch thick asbestos millboard covered with not less than 26 gage sheet metal (.017 stainless steel, .024 aluminum, or .020 copper) or equivalent protection. The protective metal over the range shall form a hood

(a) Carpeting shall not be used under a fuel-fired furnace or water heater. § 280.206 Firestopping.

(a) Firestopping of 1 inch minimum nominal lumber or the equivalent, shall be provided to cut off all concealed draft openings in all stud walls and partitions, including furred spaces, so placed that the maximum vertical dimension of any concealed space is not over eight feet. & 280.207 Requirements for foam plastic thermal insulating materials.

(a) General. Foam plastic thermal insulating materials shall not be used within the cavity of walls or ceiling or exposed to the interior of the mobile home, unless otherwise specifically approved by HUD, based on accepted tests including full scale room fire testing.

(b) Specific requirements. Foam plastic having a flame spread rating of 75 or less may be used as siding backer board or sheathing with a maximum of %inch thickness when separated from the interior of the mobile home by a minimum of 2-inches of mineral insulation or equivalent fire protective material. § 280.208 Mobile home fire detection equipment.

(a) General. At least one smoke detector (which may be a single-station alarm device) shall be installed in each mobile home to protect each separate bedroom area.

(b) Smoke detector location. A smoke detector shall be installed in the hallway or space communicating with the bed

room area.

(1) The specific location shall be in the hallway between the living room area and the first bedroom, except that when a door(s) separates the living area from the bedroom area, the detector shall be installed on the living area side as close to the door(s) as practicable.

(2) Mobile homes having bedrooms separated by any one or combination of common use areas such as kitchen, dining room, living room, or family room (but not a bathroom or utility room), shall have at least two smoke detectors, one detector protecting each bedroom

area.

(3) Where practicable, the detector shall be located between the return air intake and the living area.

(4) The architectural planning of the mobile home shall not isclate a smoke detector so as to impair its effectiveness.

(c) Smoke detectors. Smoke detectors shall be either the ionization chamber or the photoelectric wall mounted type and shall comply with all the requirements of Underwriters' Laboratories Standard No. 167 for ionization and 168 for photoelectric type detectors. Detectors shall bear the label of a testing and approval laboratory that indicates the smoke detectors have been tested and approved under the requirements of UL 167 or 168. The testing and approved laboratory shall be one which maintains a periodic follow-up service of the labeled devices to ensure compliance with the original approval.

(d) Installation. Smoke detectors shall be installed on an interior wall of the mobile home. The top of the detector shall be 5- to 7-inches from the ceiling. The detector mounting shall be attached to an electrical outlet box and the detector connected by a permanent wiring method into a general electrical circuit. There shall be no switches in the circuit to the detector other than the overcurrent protective device protecting the branch circuit.

Subpart D-Body and Frame
Construction Requirements

resist overturning and lateral movement of the mobile home from wind forces.

(3) "Tie" means strap, cable, or securing device used to connect the mobile home to ground anchors.

(4) "Diagonal Tie" means a tie intended to primarily resist horizontal forces, but which may also be used to resist vertical forces.

(5) "Vertical Tie" means a tie intended to resist the uplifting or overturning forces.

(6) "Footing" means that portion of the support system that transmits loads directly to the soil.

(7) "Ground Anchor" means any device at the mobile home stand designed to transfer mobile tome anchoring loads to the ground.

(8) "Hurricane Resistive Mobile Home" means a mobile home which meets the wind design load requirements for Zone II in § 280.305(c) (2).

(9) "Loads" (1) "Dead Loads" means the weight of all permanent construction including walls, floors, roof, partition, and fixed service equipment. (i) "Live Load" means the weight superimposed by the use and occupancy of the mobile home, including wind load and snow load, but not including dead load. (iii) "Wind Load" means the lateral or vertical pressure or uplift on the mobile home due to wind blowing in any direction.

(10) "Main Frame" means the structural component on which is mounted the body of the mobile home.

(11) "Pier" means that portion of the support system between the footing and the mobile home exclusive of caps and shims.

(12)

"Sheathing" means material which is applied on the exterior side of a building frame under the exterior weather resistant covering.

(13) "Stabilizing Devices" means all components of the anchoring and support systems such as piers, footings, ties, anchoring equipment, ground anchors, and any other equipment which supports the mobile home and secures it to the ground.

(14) "Support System" means a combination of footings, piers, caps, and shims that will, when properly installed, support the mobile home.

§ 280.303 General requirements.

(a) Minimum requirements. The design and construction of a mobile home shall conform with the provisions of this standard. Requirements for any size,

weight, or quality of material modified by the terms of "minimum." "not less than," "at least,” and similar expressions are minimum standards. The manufacturer or installer may exceed these standards provided such deviation does not result in any inferior installation or defeat the purpose and intent of this standard

(b) Construction. All construction methods shall be in conforn.ance with accepted engineering practices to insure durable, livable, and safe housing and shall demonstrate acceptable workmanship reflecting journeyman quality of work of the various trades.

(c) Structural analysis. The strength and rigidity of the component parts and/ or the integrated structure shall be determined by engineering analysis or by suitable load tests to simulate the actual loads and conditions of application that occur. (See Subparts E and J.)

(d) Hurricane resistive design. Only mobile homes which meet the applicable requirements of § 280.305 (c) (2) may be designated "Designed for Hurricane Zone." No similar designation which would imply hurricane resistance shall be used when the mobile home does not meet these requirements.

(e) New materials and methods. (1) Any new material or method of construction not provided for in this standard and any material or method of questioned suitability proposed for use in the manufacture of the structure shall nevertheless conform in performance to the requirements of this standard.

(2) Unless based on accepted engineering design for the use indicated, all new mobile home materials, equipment, systems or methods of construction not provided for in this standard shall be subjected to the tests specified in paragraph (g) of this section.

(f) Allowable design stress. The design stresses of all materials shall conform to

acceptering practice. The use of materi.otified as to strength or stress grade st... be limited to the minimum allowable stresses under accepted engineering practice.

(g) Alternate test procedures. In the absence of listed and prescribed standards, the manufacturer shall develop or cause to be developed necessary tests to demonstrate the structural properties and the significant characteristics of the method employed. Such tests shall be witnessed by an independent licensed professional engineer or architect or by a recognized testing organization. Copies of the test results shall be kept on file by the mobile home manufacturer. § 280.304

Materials.

(a) Dimension and board lumber shall not exceed 19 percent moisture content at time of installation.

(b) (1) Standards for some of the generally used materials and methods of construction are listed in the following table. (2) Materials and methods of construction utilized in the design and construction of mobile homes which are covered by the standards in the following table, or any applicable portion thereof shall comply with these requirements. (3) Engineering analysis and testing methods contained in these references shall be utilized to judge conformance with accepted engineering practices required in § 280.303 (c). (4) Materials and methods of installation conforming to these standards shall be considered acceptable when installed in conformance with the requirements of this Part. (5) Materials meeting the standards (or the applicable portion thereof) are considered acceptable unless otherwise specified herein or unless substantial doubt exists as to conformance.

Steel:

AA-1971

AISC-1973

AISI-1968

AISI-1972

AISC and SJI

AISI-1973