Appendix A
The Federal Standards That Are Dependent On Proper On-Site Completion of a Manufactured Home
One unavoidable consequence that the manufacturers and HUD/FHA could not escape was that the language in the Act was so strong that the creation of standards that carried through to the completion of a mobile home on-site was unavoidable. They could cloud how these applied, and this is the reason we have 36 different standards for installation and 14 States with no standards. So, what are the standards that can only be accomplished by assembling or completing the home on-site? Keep in mind that what is listed are Federal Construction Standards and the manufacturer must comply with these to issue a certification of compliance with ALL applicable Federal Standards.
Planning Considerations
3280.103 (b)(4) The whole house ventilation system shall not draw or expel air into the roof / ceiling system. The proper attachment of the air intake duct to the furnace for the whole house ventilation system in some instances is accomplished on-site.
3280.105 (b)(4) all exterior doors, including storm doors and screen doors, opening outward shall be provided with a safety door check. Final assembly of this safety door check is usually accomplished on site.
Fire Safety
3280.206 (c) all penetrations for pipes and vents in ceilings of furnace and water heater spaces shall be tight fitted or fire stopped. On many occasions, the final assembly of the furnace or water heater flue pipe is completed after the home is sited.
Body and Frame Construction Requirements
3280.301 minimum requirements for materials, products, equipment and workmanship needed to assure that the manufacture home will provide: (a) Structural strength and rigidity, (b) protection against corrosion, decay, insects, and other similar destructive forces, (c) protection against hazards of wind storm, (d) resistance to the elements, and (e) durability and economy of maintenance.
3280.303(a) the design and construction of a manufactured home shall conform to the provisions of the standard. The manufacturer or installer may exceed these standards provided such deviation does not result in any inferior installation or defect the purpose of the standard.
3280.303(b) all construction methods shall be in conformance 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.
3280.305(a) each manufactured home shall be designed and constructed as a completely integrated structure capable of sustaining the design load requirements of the standard and shall be capable of transmitting these loads to stabilizing devises without exceeding the allowable stresses or deflections. Improper support, stabilization and assembly of the home will prevent transmittal of these design loads.
3280.305(g)(4)(ii) holes bored in joists shall not be within 2 inches of the top or bottom of the joist, and the diameter of any such hole shall not exceed one-third depth of the joist. Holes are drilled in most instances through the joists to make the crossover electrical connections for multi-section homes.
3280.305(g)(4)(iii) Notches in the top or bottom of the joists shall not exceed one sixth the depth and shall not be located in the middle third of the span.
3280.305(g)(5) bottom board material shall be suitable for patches and the patch life shall be equivalent to the material life.
3280.305 (h)(1) roofs shall be of sufficient strength to withstand the load requirements without exceeding the deflection.
3280.306 Each manufactured home shall have provisions for support / anchoring or foundation system that when properly designed and installed will resist overturning and lateral movement (sliding) of the manufactured home as imposed by the design loads.
3280.307(a) Exterior coverings shall be of moisture and weather resistive materials and attached with corrosion resistant fasteners to resist rain, snow and wind. On multi-section homes the board covering the joint and the installation of the roof cap shingles or ridge vent.
3280.307(d) Exterior surfaces shall be sealed to resist the entrance of rodents.
Testing
3280.403(c) All primary windows and sliding glass doors shall be installed in a manner which allows proper operation and provides protection against the elements. Improper support of the home can impact window and door operation.
3280.404(c) the installation of egress windows and devices shall be installed in a manner, which allows proper operation and provides protection against the elements. Once again, improper support of the home can impact window and door operation.
3280.405(d) All swinging exterior doors shall be installed in a manner which allows proper operation and provides protection against the elements. And once again, improper support of the home can impact window and door operation.
Thermal Protection
3280.503 materials used for insulation shall be of proven effectiveness and adequate durability to assure that required design conditions concerning thermal transmission are attained. Materials used at the joint between multi-section home components.
3280.504 (c)(1) attic and roof cavities shall be vented (I) a minimum free ventilation area of not less than 1/300 of the attic or roof cavity floor area. At least 50% shall be provided by ventilators located in the upper portion of the space to be ventilated. Ridge vents improperly installed can restrict this ventilation, installation of a ridge vent can only take place on site.
3280.505 (a)(2) Joints not designed to limit air infiltration between wall to wall, wall to ceiling and wall to floor connection shall be caulked or otherwise sealed. Improper treatment at the joint between multi-section home components can fail to limit air infiltration.
Plumbing system
3280.603(a)(1) the plumbing system shall be of a durable material, free from defective workmanship and so designed and constructed as to give satisfactory service for a reasonable life expectancy.
3280.603(b)(4) all piping and fixtures subject to freezing temperatures shall be insulated or protected to prevent freezing under normal occupancy.
3280.603 (b)(6) all exterior openings around piping and equipment shall be sealed to resist the entrance of rodents.
3280.605 (a) joints and connections in the plumbing system shall be gas tight and water tight for the pressures required under the testing procedure. An incomplete gas or water system cannot be tested until the on-site assembly or completion of these systems has been accomplished.
3280.605 (a)(1) all joints and connections shall be correctly assembled for tightness. The plumbing system can only by completed on-site and this cannot be known until this has occurred.
3280.605 (a)(4) & 3280.609 (e)(5) Plastic pipe and fittings shall be joined by installation methods recommended by the manufacturer or in accordance with a listed standard.
3280.608 (a) piping in a plumbing system shall be installed without undue stress and strains, and provisions make for expansion.
3280.608 (b) piping shall be secured at sufficiently close intervals to the pipe in alignment and carry the weight of the pipe and contents. Plastic drainage pipe shall be supported at intervals not to exceed 4 feet and plastic water pipe shall be supported at intervals not to exceed 3 feet.
3280.608 (c) Hangers and anchors shall be of sufficient strength to support their proportional share of the pipe alignments and prevent rattling.
3280.608 (c)(2) piping shall be securely attached to the structure by hangers, clamps or brackets.
3280.608 (c)(3) hangers and straps supporting plastic pipe shall not compress, distort, cut, or abrade the piping and shall allow for free movement of the pipe.
3280.610 (c)(1) each manufactured home shall have only one drain outlet.
3280.610 (h) horizontal drainage piping shall have a uniform grade of not less than 1/4 inch per foot toward the manufactured home drain outlet.
Heating, Cooling and Fuel Burning Systems
3280.704 (c) Oil Tanks, (1) Installation. Oil tanks and listed automatic pumps (oil lifters) installed for gravity flow of oil to heating equipment shall be installed so that the top of the tank is no higher than 8 feet above the appliance oil control and the bottom of the tank is not less than 18 inches above the appliance oil control.
3280.704 (c)(2) a readily accessible approved manual shut off valve shall be installed at the outlet of an oils supply tank. The tank shall be installed to close against the supply.
3280.704 (c)(3) all oil tanks shall be equipped with an approved oil filter or strainer located downstream from the tank shutoff valve. The fuel oil filter or strainer shall contain a sump with a drain for the entrapment of water.
3280.705 (a) all exterior openings around piping, ducts, plenums or vents shall be sealed to resist the entrance of rodents.
3280.705 (c)(5) the (gas line) connection between units....A shutoff valve of the non displacement rotor type suitable for outdoor use shall be installed at each crossover point upstream of the connection when listed connectors are used. In many instances the shutoff valve is not factory installed.
3280.706 (b) (Oil piping systems) all materials used for the installation, extension, alteration, or repair, of any oil piping system shall be new and free from defects. Most oil piping is not factory installed.
3280.707 (b) (Heat producing appliances) fuel burning heat-producing appliances shall be vented to the outside.
3280.708 (a) (Clothes dryers) all gas and electric clothes dryers shall be exhausted to the outside by a moisture-lint exhaust duct and termination fitting.
3280.709 (e)(5) (AC installation) a cooling coil is installed with a forced air furnace, the coil shall be installed in accordance with its listing. The AC compressor and cooling coil are always installed on site.
3280.709 (g)(1)(vii) (Fireplaces) the chimney shall extend at least three feet above the part of the roof through which it passes and at least two feet above the highest elevation of any part of the manufactured home within 10 feet of the chimney. Most fireplace chimneys are not factory installed.
3280.710 (a)(2) (Venting, ventilation and combustion air) draft hood connectors shall be firmly attached to the draft hood outlets or flue collars.
3280.710 (a)(3) every joint of a vent, vent connector, exhaust duct and combustion air intake shall be secured and in alignment.
3280.714 (b) (Appliances, cooling) the installation of each appliance shall conform to the terms of its listing as specified on the appliance and in the manufacturer's instructions in the home. The installer shall include the manufacturer's instructions in the home.
3280.715 (a)(5)(ii) the (crossover) duct shall not be in contact with the ground.
Electrical Systems
3280.801 (d) all electrical materials, devices, appliances, fittings and other equipment shall be listed or labeled by a nationally recognized testing agency and shall be connected in an approved manner when in service. Many fixtures and appliances such as ceiling fans, outdoor lights, and hanging lights are not factory installed.
3280.809 (d) all exposed non-current carrying metal parts that may become energized shall be effectively bonded. The bonding together of chassis in multi-section homes is accomplished at the home site.