and keys, door chain and attachments, storm door latch, chain and attachments, threshold extension, screw cover, drip cap. (2) Workmanship. All construction methods, materials and workmanship shall be in conformance with accepted engineering practices to insure durable, livable, and safe housing. (d) Materials and methods. Any material or method of construction, whether or not provided for in this standard, and any material or method of questioned suitability, proposed for use in manufacture, shall nevertheless conform in performance as outlined in paragraph (e) of this standard and proof of capability of structural integrity shall be presented. If applicable, units shall comply with the following: (1) Wood and wood based products(i) Wood. Wood door parts shall be manufactured of suitable lumber having a moisture content of 6 to 12 percent at time of fabrication. Wood parts except interior trim shall be manufactured utilizing wet-use adhesive requirements as defined in ASTM D-3110 and Preservative Treated in accordance with NWMA I.S.-4 standard. Doors shall conform to the Type 1 requirements of NWMA I.S. 1-74. (ii) Plywood. Plywood shall be exterior type and preservative treated in accordance with NWMA I.S.-4. (iii) Hardboard parts shall meet or exceed the requirements for % inch tempered hardboard in accordance with the latest edition of PS 58. (2) Hardware and fasteners. All hardware components and fasteners when considered as individual components, whether commercially available, or proprietary, must be capable of performing to the criteria stipulated in this section and in the Performance Requirements Section, Paragraph (e) of these specifications. (3) Glass. All glazing in doors shall be safety glazing material meeting ANSI Z97.1-72. Glass in jalousies shall also be at least 32 in. in thickness and not longer than 36 inches. Exposed edges shall be seamed, ground or polished to prevent injury. (4) Weatherstripping. A tight threshold and weatherstripping to reduce air infiltration and improve water resis tance shall be provided capable of conforming to the criteria stipulated in the Performance Requirements Section, Paragraph (e) of this standard. (e) Performance requirements—(1) Size of test specimen. All tests shall be performed on exterior passage door units with all operable portions closed and all criteria herein are applicable to exterior passage doors of the largest type that the producer desires to qualify under this specification. No inference of compliance to these requirements is to be made for products exceeding the size of the test specimen 'submitted. Largest unit size is determined by the maximum width and height dimensions of production units that are equal to or less than corresponding dimensions in that unit tested and passed. (2) Structural performance test—(i) Wind pressure resistivity. There shall be no glass breakage or permanent deflection or any other condition which would cause the specimen to be inoperable after being subjected to exterior pressures of 25 pounds per square foot. The test method applicable to this requirement shall be ASTM E330. (ii) Interior pressure. There shall be no glass breakage or permanent deflection or any other condition which would cause the specimen to be inoperable after being subjected to an interior pressure equal to 1⁄2 the requirements in paragraph (e)(2)(i). The test method applicable to this requirement shall be ASTM E-330 except that no artificial means of containing pressure shall be allowed. Should pressure not be obtainable due to lack of air, the testing agency will report the pressure achieved, the theoretical air flow supplied to the unit, and certify that no additional flow from the equipment in use was available. Laboratory equipment used for this test must be capable of developing 10 x air flow determined in paragraph (e)(2)(iii) of this specification. (iii) Air infiltration test. Air infiltration shall not exceed the limits set forth below when tested in accordance with ASTM E-283 at an exterior pressure differential of 1.56 pounds per square foot (0.300" water pressure). 1.35 CFM per sq. ft. of door. 1.2 CFM per sq. ft. of door. Jan. 1, 1975. Jan. 1, 1976. 1.0 CFM per sq. ft. of door.................... Jan. 1, 1977. (iv) Water resistance test. No water shall pass the interior face of the test specimen at a test pressure of 0 psf when tested in accordance with ASTM E-331. (v) The sequence of tests shall be performed as they are listed above. The Air Infiltration Test may be performed after the Water Resistance Test providing all sealed areas are thoroughly dried. Subpart F-Thermal Protection § 280.501 Scope. This subpart sets forth the requirements for condensation control, air infiltration, thermal insulation and certification for heating and comfort cooling. § 280.502 Definitions. (a) The following definitions are applicable to Subpart F only: (1) "Pressure Envelope" means that primary air barrier surrounding the living space which serves to limit air leakage. In construction using ventilated cavities, the pressure envelope is the interior skin. (2) "Thermal Envelope Area" means the sum of the surface areas of outside walls, ceiling and floor, including all openings. The wall area is measured by multiplying outside wall lengths by the inside wall height from floor to ceiling. The floor and ceiling areas are considered as horizontal surfaces using exterior width and length. (b) Exterior walls. (1) Exterior walls shall have a vapor barrier not greater than 1 perm (dry cup method) installed on the living space side of the wall, or (2) Unventilated wall cavities shall have an external covering and/or sheathing which forms the pressure envelope. The covering and/or sheathing shall have a combined permeance of not less than 5.0 perms. In the absence of test data, combined permeance may be computed using the formula: Protal=(1/[(1/P1)+(1/P2)]) where P, and P, are the permeance values of the exterior covering and sheathing in perms. Formed exterior siding applied in sections with joints not caulked or sealed shall not be considered to restrict water vapor transmission, or (3) Wall cavities shall be constructed so that ventilation is provided to dissipate any condensation occurring in these cav ities. § 280.505 Air infiltration. (a) Envelope air infiltration. The opaque envelope shall be designed and constructed to limit air infiltration to the living area of the home. Any design, material, method or combination thereof which accomplishes this goal may be used. The goal of the infiltration control criteria is to reduce heat loss/heat gain due to infiltration as much as possible without impinging on health and comfort and within the limits of reasonable economics. (1) Envelope penetrations. Plumbing, mechanical and electrical penetrations of the pressure envelope not exempted by this part, and installations of window and door frames shall be constructed or treated to limit air infiltration. Penetrations of the pressure envelope made by electrical equipment, other than distribution panel boards and cable and conduit penetrations, are exempt from this requirement. Cable penetrations through outlet boxes are considered exempt. (2) Joints between major envelope elements. Joints not designed to limit air infiltration between wall-to-wall, wall-to-ceiling and wall-to-floor connections shall be caulked or otherwise sealed. When walls are constructed to form a pressure envelope on the outside of the wall cavity, they are deemed to meet this requirement. § 280.506 Heat loss. The mobile home heat loss/heat gain shall be determined by methods outlined in §§ 280.508 and 280.509. The outdoor winter design temperature zone for which the mobile home is acceptable and the lowest outdoor temperature to which the installed heating equipment will maintain a temperature of 70 F shall be certified as specified in § 280.510 of this subpart. (a) Transmission Heat Loss Coefficient. The overall coefficient of heat transmission of the mobile home for the respective zones and an indoor design temperature of 70 F, including internal and external ducts, and excluding infiltration ventilation and condensation control, shall not exceed the B.T.U./(hr.) (sq. ft.) (F) of the mobile home envelope area as tabulated below rior walls, floors, and ceilings shall be provided with thermal insulation. (c) Mobile homes designed for Zones II and III shall be factory equipped with storm windows or insulating glass. § 280.507 Comfort heat gain. Information necessary to calculate the home cooling load shall be provided as specified in this Part. (a) Transmission heat gains. Homes complying with this section shall meet the minimum heat loss transmission coefficients specified in § 280.506(a). § 280.508 Heat loss, heat gain and cooling load calculations. Information, values and data necessary for heat loss and heat gain determinations shall be taken from the 1972 ASHRAE Handbook of Fundamentals. Infiltration and Ventilation-Chapter 19. Determining "R" & "U" Value-Charter 20. Heating Load-Chapter 21. Cooling Load Calculations-Chapter 22. Outdoor Winter Design Temperatures (Use 972 percent values)-Chapter 33. Outdoor Summer Design Temperatures (Use 21⁄2 percent values)-Chapter 33. § 280.509 Criteria in absence of specific data. In the absence of specific data, for purposes of heat-loss/gain calculation, the following criteria shall be used: (a) Infiltration Heat Loss. In the absence of measured infiltration heat loss data, the following formula shall be used to calculate heat loss due to infiltration and intermittently operated fans exhausting to the outdoors. The perimeter calculation shall be based on the dimensions of the pressure envelope. Infiltration Heat-Loss-0.7 (T) (ft. of perimeter), BTU/hr. where: T-70 minus the heating system capacity certification temperature stipulated in the Heating Certificate, in F. (b) Framing areas. 15 percent of wall area less windows and doors. Floor and Ceiling....... 10 percent of the area. (c) Insulation compression. Insulation compressed to less than nominal thickness shall have its nominal Rvalues reduced for that area which is compressed in accordance with the following graph: When insulation is installed over the framing members the thermal performance of the insulation is reduced due to compression at the framing members. The Resistance value of the insulation between the framing members is reduced by 12.5 percent for framing members 16" O.C., 8.5 percent for framing members 24" O.C., and 4 percent for framing members 48" O.C. (d) Air supply ducts within floor cavity. Air supply ducts located within a floor cavity shall be assumed to be heating or cooling the floor cavity to living space temperatures unless the duct is structurally isolated by the framing system or thermally insulated from the rest of the floor cavity with a thermal insulation at least equal to R4. (e) Air supply ducts within ceiling cavity. Where supply ducts are located in ceiling cavities, the influence of the duct on cavity temperatures shall be considered in calculating envelope heat loss or heat gain. (f) The supply duct loss (and/or heat gain where applicable-See § 280.511) shall be calculated using the actual duct surface area and the actual thickness of insulation between the duct and outside of the mobile home. If there is an air space of at least 1⁄2 inch between the duct and the insulation, heat loss/gain need not be calculated if the cavity in which the duct is located is assumed to be at living space temperature. The average temperature inside the supply duct, including ducts installed outside the mobile home, shall be assumed to be 130 F for purposes of calculation of heat loss and 60 F for heat gain. (g) Return air cavities. Cavities used as return air plenums shall be considered to be at living space temperature. § 280.510 Heat loss certificate. The mobile home manufacturer shall permanently affix the following "Certificate" to an interior surface of the home that is readily visible to the homeowner. The "Certificate" shall specify the following: (a) Heating zone certification. The design zone at which the mobile home heat loss complies with § 280.506(a). (b) Outdoor certification temperature. The lowest outdoor temperature at which the installed heating equipment will maintain a 70 F temperature inside the home without storm sash or insulating glass for Zone I and with storm sash or insulating glass or Zones II and III and complying with §§ 280.508 and 280.509. HEATING CERTIFICATE Home Manufacturer Plant Location Home Model (Include Winter Climate Zone Map) This mobile home has been thermally insulated to conform with the requirements of the Federal Mobile Home Construction and Safety Standards for all locations within climatic Zone——. Heating Equipment Manufacturer The above heating equipment has the capacity to maintain an average 70 F temperature in this home at outdoor temperatures of --F. To maximize furnace operating economy and to conserve energy it is recommended that this home be installed where the outdoor winter design temperature (97%) is not higher than -- degrees Fahrenheit.' The above information has been calculated assuming a maximum wind velocity of 15 MPH at standard atmospheric pressure. 'The temperature to be specified shall be 20 F or 30% of the design temperature difference, whichever is greater, added to the temperature specified as the heating system capacity certification temperature without storm windows or insulating glass for Zone I and with storm windows or insulating glass for Zones II and III. Design temperature difference is 70 minus the heating system capacity certification temperature in degrees Fahrenheit. § 280.511 Comfort cooling certificate and information. (a) The mobile home manufacturer shall permanently affix a "Comfort Cooling Certificate" to an interior surface of the home that is readily visible to the home owner. This certificate may be combined with the heating certificate required in § 280.510. The manufacturer shall comply with one of the following three alternatives in providing the certificate and additional information concerning the cooling of the mobile home: (1) Alternative 1. If a central air conditioning system is provided by the home manufacturer, the heat gain calculation necessary to properly size the air conditioning equipment shall be in accordance with procedures outlined in Chapter 22 of the ASHRAE Handbook of Fundamentals, with an assumed location and orientation. The following information shall be supplied on the Comfort Cooling Certificate: "Air Conditioner ManufacturerAir Conditioner Model Certified Capacity-B.T.U./Hr. in accordance with the appropriate Air Conditioning and Refrigeration Institute Standards. The central air conditioning system provided with this home has been sized, assuming an orientation of the front (hitch) end of the home facing---- and is designed on the basis of a 75 F indoor temperature and an outdoor temperature of F dry bulb and - F wet bulb." Example Alternate 1 COMFORT COOLING CERTIFICATE Mobile Home Mfg Air Conditioner Manufacturer Certified Capacity-B.T.U./Hr. in accordance with the appropriate Air Conditioning and Refrigeration Institute Standards. The central air conditioning system provided with this home has been sized assuming an orientation of the front (hitch end) of the home facing On this basis the system is designed to maintain an indoor temperature of 75 F when outdoor temperatures are F dry bulb and - - F wet bulb. The temperature to which this home can be cooled will change depending upon the 30-053 0 - 78 - 57 |