15/32" CDX PLY W/ RADIANT BARRIER (COMMON NAILS) 2X ROOF RAFTERS (SEE PAGE 2) R-30 BATT. INSUL / CLIMATE ZONES14 AND 16

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1 2017 COUNTY OF LOS ANGELES RESIDENTIAL CODE WOOD FRAME PROVISIONS DEAD LOAD SHALL NOT EXCEED 15 PSF FOR COMBINED ROOF / CEILING OR EXTERIOR WALLS AND PSF FOR FLOORS OR PARTITIONS. THIS SHEET IS FOR INFORMATION AND REFERENCE ONLY AND IS NOT A SUBSTITUTE FOR ACCURATE DRAWINGS PREPARED FOR EACH PROPOSED CONSTRUCTION PROJECT. 15/32" CDX PLY W/ RADIANT BARRIER (COMMON NAILS) SEE PAGE 3 FOR CONNECTION REQUIREMENTS 2X ROOF RAFTERS 2x CEILING JOISTS 3" MIN. CEILING JOIST BEARING WALL W/ NAILS PER RAFTER TIE CONNECTIONS R-30 BATT. INSUL / CLIMATE ZONES1 AND 16 EAVES EXTENDING CLOSER THAN 5'-0" TO PROPERTY LINE SHALL BE OF 1-HR CONSTRUCTION, SEE NOTE 16. 8" MIN NAT. GRADE EXTERIOR BEARING WALL 7'-0" MIN. CEILING HEIGHT SEE NOTE #1 DOUBLE TOP PLATE WHERE STUCCO IS APPLIED OVER WOOD STR. PANEL, PROVIDE 2-LAYERS GRADE PAPER UNDER LATH 2X P.T. SILL W/ 6'-0" O.C. W/ 0.229" X 3" X 3" PLATE WASHERS " CONC. SLAB W/ 16" O.C. EACH WAY W/ TWO LAYERS OF 2" ND FILL WITH 6 MIL MOISTURE BARRIER MEMBRANE BETWEEN THE TWO O,C, FOR JOIST SPANS OVER 8'-0" INTERIOR BEARING WALL 2X SOLID BLOCKING DOUBLE TOP PLATE 2X STUD oc (STUD GRADE) R-13 BATT INSUL. / ZONES 1 & 16 2X SOLID BLOCKING AT JOIST SPLICE LAP 3" MIN. W/ 3-16d BRACED WALL PANEL (SEE PAGE ) 5/8" T&G PLY W/ 6"/6"/12"oc 2X FLOOR JOISTS EXTERIOR BEARING WALL 2'-0" Min. 5' - 0" MIN. OR PER ZONE REQUIREMENTS SEE NOTES 12, 13, & 1 R-19 BATT INSUL. 2X RIM JOIST PROPERTY LINE 2X P.T. SILL W/ 6'-0" O.C. W/ 0.229" X 3" X 3" PLATE WASHERS SEE PAGE 5 FOR FOUNDATION REQUIREMENTS 2X P.T. SILL & ANCHOR BOLT NAT. GRADE X GIRDER X P.T. POST W/ POST CAP 6"MIN. FOUNDATIONS SHALL BE BASED ON EXPANSIVE SOILS, U.N.O. 6" 8" 12" MIN. POURED CONC. PIER W/ POST BASE NAT. GRADE 8" SEE PAGE 5 FOR FOUNDATION REQUIREMENTS WALL SECTION: SLAB-ON-GRADE CONSTRUCTION WALL SECTION: RAISED FLOOR CONSTRUCTION Notes: 1. Anchor bolts: 1/2" Ø x "; minimum 7" embedment, with minimum 2 anchor bolts per plate section, located not more than 12" or less than " from each end of the section. 2. All foundation plates or sills and sleepers on a concrete or masonry slab, which is in direct contact with earth, and sills that rest on concrete or masonry foundations, shall utilize preservative treated wood (AWPA U1) & field-cut ends, notches and drilled holes shall be field treated (AWPA M). Fasteners, including nuts and washers, for preservative treated wood or fire-retardant treated wood shall be of hot-dipped, zinc-coated galvanized steel or stainless steel. 3. Minimum concrete Strength: 2500psi. Bearing walls and braced wall panels require continuous footings (R03.1). 5. Soil report is required if the proposed construction is located in a liquefaction, landslide, Alquist-Priolo, Sierra Madre or other earthquake fault zone. 6. Where interior walls are shear wall panels, wall framing and sheathing shall extend to the roof sheathing. 7. Under floor spaces shall be ventilated by openings into the under-floor space walls. Such openings shall have a net area of not less than 1 sq. ft. for each 150 sq. feet of under-floor area. Openings shall be located within 3 ft. of each corner of the building and provide cross ventilation. The openings shall be approximately equally distributed along the length of at least two sides. Corrosion resistant mesh w/ 1/" openings. 8. The net free ventilating area of enclosed attics & enclosed rafter spaces shall not be less than 1/150 of the space ventilated and shall have cross ventilation for each separate space. 9. For projects in Very High Fire Hazard Severity Zone (VHFHSZ): see VHFHSZ Plan Review List.. Provide a minimum of 1" airspace between insulation and the roof sheathing. 11. Exterior walls of dwellings and accessory structures closer than 5 ft. (non-sprinklered) / 3 ft. (sprinklered) to the property line shall be 1-hour fire-resistance-rated construction. 12. No openings other than approved foundation vents shall be permitted in the exterior walls of dwellings and accessory buildings where the exterior walls are less than 3-ft. to the property line. 13. The area of exterior wall openings of non-sprinklered dwellings and accessory buildings located 3-ft. and < 5-ft. to the property line shall be limited to 25% of the wall area. The area of exterior wall openings is unlimited when exterior walls are located 5-ft. for non-sprinklered buildings and 3-ft. for sprinklered buildings. 1. Footings on or adjacent to slopes shall meet the requirements of Section R Exterior plaster (stucco) walls shall be provided with corrosion-resistant weep screeds. 16. Roof eave fire-resistance rating shall be permitted to be reduced to 0 hours on the underside of the eave if fireblocking is provided form the wall top plate to the underside of the roof sheathing. VER. 7.0 ( ) 1

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3 D/6 MAX. 2" MIN. D/6 MAX. 2" MIN. D/3 MAX. D/3 MAX. 1/3 NOTCHING & BORING OF FLOOR JOISTS, RAFTERS, AND CEILING JOISTS (NOTCHING NOT PERMITTED IN MIDDLE 1/3 JOIST SPAN) D/ MAX. D/ MAX. 25% MAX. 0% MAX. 0% MAX. EXTERIOR WALLS AND BEARING PARTITIONS 5/8" MIN. 5/8" MIN. 60% MAX. OR EACH BORED STUD DOUBLED. NOT PERMITED IN MORE THAN 2 DOUBLE STUDS NON-BEARING PARTITIONS 18 GA. O.C. 2:12 TO :12 SLOPE W/ 2-LAYERS TYPE 15 FELT :12 OR GREATER SLOPE W/ 1-LAYER TYPE 15 FELT 2-16d EACH SIDE D/ MAX. CANTILEVER NOT TO EXCEED 2 INCHES ROOF SHEATHING JOIST DEPTH AT TAPER CUT D/ MAX. 2X ROOF RAFTER NOT LESS THAN 3-1/2 INCHES ROOF SLOPE-COMP SHINGLES (R905.2) RIDGE (R802.3) NAILS (TABLE R602.3(1)) RAFTER TIE CONNECTION B.N. 8d@6" OC 2 X RIDGE BOARD- DEEPER THAN CUT END OF ROOF RAFTER 15/32" CDX PLY W/ 6"/6"/12" (COMMON NAILS) NOTCHING & BORING: FLOOR JOISTS (R502.8), RAFTERS/CEILING (R ), WALL STUDS (R602.6) B.N. 6" O.C. ROOF RAFTER B.N. 6" O.C. ROOF RAFTER W/ FRAMING EACH BLOCK 2X SLOPED ROOF RAFTER " O.C. 3-d NAILS 5 o BRACED WALL PANEL (SEE PAGE ) W/ FRAMING EACH BLOCKING CEILING JOIST INTERIOR SHEAR WALL AT ATTIC 2X CEILING JOIST GABLE SUPPORT RAFTER SPAN PURLIN CONTINUOUS BETWEEN SUPPORT BRACES AND ME SIZE AS RAFTER 2X SOLID BLOCKING 2X DOUBLE TOP PLATE 2X STUDS 5 DEG. MIN. BRACED RAFTER CONSTRUCTION (R ) RAFTER SPAN HEADER (SEE PAGE 2 FOR SPAN) 2X PURLIN SUPPORT '-0" O.C. 2X RIDGE BOARD 2X ROOF RAFTERS NAIL TO JOIST 12 3 MIN. SLOPE CEILING JOISTS AT CEILING JOIST SPLICE PROVIDE NAILS PER RAFTER TIE CONNECTIONS BEARING PARTITIONS NOTCH GREATER THAN 50PERCENT OF THE PLATE WIDTH TOP PLATES DRILLING & NOTCHING OF TOP PLATE (R ) CONT. DOUBLE TOP PLATE 16 GAGE AND 1.5" WIDE METAL TIE EACH SIDE OF NOTCH W/ 8-d NAILS EACH SIDE SOLID ALL UNSUPPORTED PLYWOOD EDGES ' MAX. HEADER (SEE PAGE 2 FOR SPAN) ANCHOR BOLTS MIN. 1/2" DIA. x ", 7" EMBEDMENT 2X SILL PLATE 2 # TOP & BOTTOM. TIE DOWN EACH SIDE OF PANEL (1800# MIN. CAPACITY) PER PAGE THICKEN FOOTING AS REQUIRED FOR BOLT EMBEDMENT DEPTH MIN. 2 ANCHOR BOLTS PER BRACED WALL PANEL, MAX 12" & MIN. " FROM EACH END OF THE PLATE SECTION VER. 7.1 ( ) 3

4 H (HEIGHT OF PANEL) ' MAX. 8" MIN. FOR METHOD WSP AND 96" MIN. FOR GB & PCP NO PENETRATIONS PERMITTED IN BRACED WALL PANELS SEE NOTE 1. MIN. 2 BRACED WALL PANELS ARE REQUIRED IN EACH BRACED WALL LINE NOTES: 1. BRACED WALL LINES AT EXTERIOR WALLS SHALL HAVE A BRACED WALL PANEL LOCATED AT EACH END OF THE BRACED WALL LINE. EXCEPTION: FOR METHOD WSP, THE BRACED WALL PANEL SHALL BE PERMITTED TO BEGIN NO MORE THAN FEET FROM EACH END OF THE BRACED WALL LINE PROVIDED: A UP TO ' METHOD WSP BRACING ONLY BRACED WALL LINE LENGTH 25'-0" MAX. (TYP) BWL BWL BWL 25'-0" MAX. (TYP) 25'-0" MAX. (TYP) ' MAX OFFSET ' MAX OFFSET DESIGNATED BRACED WALL LINE (BWL) BWL B OR 2" 2" A MIN. 2" PANEL IS APPLIED TO EACH SIDE. THIS 2" WIDE PANEL DOES NOT COUNT AS BRACING UP TO ' METHOD WSP BRACING ONLY BRACED WALL LINE LENGTH 1800 LBF TIE-DOWN DEVICES REQUIRED AT THE ENDS OF EACH BRACED WALL PANEL CLOSEST TO THE CORNER 2. MIXING BRACING METHODS WITHIN A BRACED WALL LINE IS NOT PERMITTED. INTERMITTENT BRACING METHODS BASED ON SEISMIC DESIGN CATEGORY (AS A FUNCTION OF BRACED WALL LINE LENGTH) a ROOF/CEILING DEAD LOAD = 15 PSF WALL HEIGHT = FT FLOOR DEAD LOAD = PSF BRACED WALL LINE SPACING < 25 FT SOIL CLASS = D VER. 7.0 ( ) MINIMUM TOTAL LENGTH (feet) OF BRACED WALL PANELS REQUIRED ALONG EACH BRACED WALL LINE f SEIMIC DESIGN BRACED WALL METHODS GB b,e STORY LOCATION CATEGORY (SDC) LINE LENGTH AND PCP c,e METHOD WSP d SDC D 0 OR D SDC D FOR SI: 1 foot = 30.8 mm, 1 pound per square foot = 7.89 Pa. a. Based on Table R602..3(3) of the 2017 County of Los Angeles Residential Code. b. Method GB (Gypsum Board) = 1/2" minimum thickness gypsum board with 1-1/2" galvanized roofing nail or 1-1/" screws, Type W or S for exterior sheathing, or 5d cooler nails, 0.086" diameter, 1-5/8" long, 15/6" head for interior sheathing. Maximum spacing of fasteners shall be at 7" o.c. at panel edges, including top and bottom plates. When Method GB panels are applied to only one face of a braced wall panel, the minimum total length of braced wall panel in the Table shall be doubled. c. Method PCP (Portland Cement Plaster) = 7/8" minimum thickness Portland cement plaster with 1-1/2", 11 gage, 7/16" head nails at 6" spacing (for maximum 16" stud spacing only). Gypsum wall board (1/2" minimum thickness shall be installed on the side of the wall opposite the bracing material, except if the minimum total length of braced wall panel in the Table is multiplied by a factor of 1.5. d. Method WSP (Wood Structural Panel) = 15/32" minimum thickness wood structural panel with 8d common (2-1/2" x 0.131") nails at 6" spacing (panel edge) at 12" spacing (intermediate supports), 3/8" edge distance to panel edge. Gypsum wall board (1/2" minimum thickness) shall be installed on the side of the wall opposite the bracing material, except if the minimum total length of braced wall panel in the Table is multiplied by a factor of 1.5. e. Method GC and PCP braced wall panel h/w ratio shall not exceed 1:1. f. Linear interpolation shall be permitted.

5 FOUNDATION SYSTEM ON EXPANSIVE SOIL FOR 1 OR 2 STORY R-3/ ACCESSORY U OCCUPANCIES DOUBLE FLOOR JOIST UNDER PARALLEL PARTITION INTERIOR BEARING WALL EXTERIOR WALL GIRDER GIRDER CONTINUOUS 2 # BARS, TOP AND BOTTOM 12" MIN. 8" MIN. 18" 2" MIN. 3" MIN. 16" SQUARE (SINGLE STORY) TWO LAYERS OF 2-INCH ND FILL WITH 6 MIL. MOISTURE BARRIER MEMBRANE BETWEEN THE TWO LAYERS " SLAB ON GRADE, REINFORCED WITH 16" O.C. EACH WAY. TURATE SOIL 18" DEEP PRIOR TO POURING SLAB # 16" O.C. FOR TWO POUR TYP. NOTES: 1. SOLID BLOCKED CRIPPLE WALLS (IF USED), SHALL NOT EXCEED 1" IN HEIGHT WITHOUT ENGINEERING ANALYSIS. 2. PERIMETER WALLS, INTERIOR BEARING WALLS AND POSTS SUPPORTED ON CONTINUOUS FOUNDATIONS MIN. FOOTING FOR SUPPORTING ONE AND TWO FLOORS RESPECTIVELY.. SHEAR TRANSFER DETAILS AND OTHER REQUIREMENTS NOT SHOWN FOR CLARITY. VER 7.0 ( ) 5 20" MIN. 3" MIN. CONTINUOUS 2 # BARS, WITHIN " OF TOP & BETWEEN 3" AND " OF BOTTOM 20" MIN. 8" MIN. 2" MIN.

6 SEISMIC STRAPS: TWO MIN. APPROVED SEISMIC STRAPS APPLIED PER MANUF. SPECS T&P VALVE PIPED TO EXTERIOR 3/" MIN. PIPE. NO THREADS ALLOWED IN BOTTOM PIPING EXTERIOR WALL TOP 1/3 PER MANUF. RECOMENDATION LISTED CAP LISTED GAS VENT VENT INSTALLATION PER. MANUF. SPECIFICATION 12" MIN. FOR ROOF SLOPE: FLAT TO <6:12 " 6" MIN. 2" MAX BOTTOM 1/3 ROOF SLOPE: FLAT TO <6:12 RAISE 18" IN GARAGE GARAGE FLOOR NOTE: NO GAS-FIRED WATER HEATER ALLOWED IN BEDROOMS, BATHROOMS, CLOTHES CLOSETS, OR ANY SPACE OPENING INTO A BEDROOM OR BATHROOM. WATER HEATER (MC305.1, PC507.2, PC507.13) VENT (PC ) 20" CLEAR 30" CLEAR 36" CLEAR OPENABLE AREA 2" CLEAR OPENABLE AREA " MAX SINGLE CASEMENT: 2- X -0, 2-6 X 3-6 DOUBLE CASEMENT: -8 X -0 CASEMENT/ FIXED COMBO: 7-0 X -0 OTHER WINDOW TYPES: AWNING & BAY W/ FIXED CENTER: NONE W/O MANUF. DATA SINGLE/ DOUBLE HUNG: 3-0 X 5-0, 3-0 X 5-6,3- X 5-0, 3-8 X 5-0, -0 X 5-0 SINGLE/ FIXED COMBO: NONE W/O MANUF. DATA SLIDER: -0 X X X 3-0 SLIDER/ FIXED COMBO: 8-0 X -0-0 X X 3-0 MIN. SIZE WINDOW FOR 20" CLEAR WIDTH AND 5.0 S.F. OPENABLE AREA MIN. SIZE WINDOW FOR 2" CLEAR HEIGHT AND 5.0 S.F. OPENABLE AREA 1. 20" MIN. CLEAR WIDTH 2. 2" MIN. CLEAR HEIGHT SF MIN. OPENABLE AREA AT GRADE-FLOOR ONLY, 5.7 SF MIN. ELSEWHERE. " MAX FLOOR LEVEL NOTE: SIZES ARE TAKEN FROM DATA SUPPLIED BY WINDOW MANUFACTURERS. HOWEVER, THESE ARE GENERAL DIMENSIONS AND MUST BE VERIFIED WITH ACTUAL WINDOWS INSTALLED TO MEET MINIMUM EGRESS REQUIREMENTS. EMERGENCY ESCAPE/ RESCUE OPENING (R3) 1/2" MIN. CLEAR ON TOPS, SIDES AND ENDS 5 PIPE Ø +1" 8" 6" NO PIPES CONC. FOUND. WALL FLOOR GIRDER 2'-0" MIN. NO SURCHARGE ALLOWED ON SEWER PIPE PIPE DEPTHS TO 3'-0" MAX. BELOW FOOTING P.T. SILL SLEEVES REQUIRED AT PENETRATION OF FOOTING FOR ANY PIPES 3" MIN. BEARING TRENCHES AT FOOTINGS VER 7.0 ( ) 6 GIRDER (R317.1 / R502.6)

7 LIVING DRYER VENT " Ø MIN.; 1' MAX. W/ TWO 90 BENDS FOR METAL DUCT; 6' MAX. FOR FLEX DUCT CONNECTOR; 0 SQ.IN. MIN. FREE OPENING. (MC50..2) ALL WINDOWS WITHIN 2" OF DOORS SHALL BE TEMPERED (R308.) BATHROOMS SHALL BE PROVIDED WITH 50 CFM INTERMITTENT VENTILATION (R303.3) DINING 18"X2" UNDERFLOOR ACCESS (R08.) EMERGENCY ESCAPE / RESCUE WINDOW (SEE PAGE 6) SEE NOTE 2 CMA HALL BEDROOM SEE NOTE 2 12"X12" TUB ACCESS CMA F 30" MIN. (PC 02.5) 2" MIN. CLEAR IN FRONT OF TOILET (PC 02.5) BEDROOM RESIDENTIAL REQUIREMENTS: NOTES: 1. AN AUTOMATIC RESIDENTIAL FIRE SPRINKLER SHALL BE DESIGNED AND INSTALLED IN ACCORDANCE WITH SECTION R313.3 OR NFPA 13D FOR A NEW ONE- AND TWO-FAMILY DWELLING. (R313) 2. CARBON MONOXIDE (CMA) AND SMOKE ALARMS () ARE REQUIRED FOR ALTERATIONS, REPAIRS OR ADDITIONS WHERE A PERMIT VALUATION EXCEEDS $1,000 (R31 & R315): A. CARBON MONOXIDE ALARMS SHALL BE PROVIDED IN EXISTING DWELLINGS OR SLEEPING UNITS THAT HAVE ATTACHED GARAGES OR FUEL-BURNING APPLIANCES. LOCATE SUCH ALARMS OUTSIDE OF EACH SEPARATE DWELLING UNIT SLEEPING AREA IN THE IMMEDIATE VICINITY OF THE BEDROOM(S). B. SMOKE ALARMS SHALL BE INSTALLED IN EACH SLEEPING ROOM AND OUTSIDE OF EACH SEPARATE SLEEPING AREA IN THE IMMEDIATE VICINITY OF THE BEDROOM(S). NEW CONSTRUCTION - 120V WITH BATTERY BACKUP AND INTERCONNECTED. EXISTING CONSTRUCTION - BATTERY OPERATED. 3. GARAGE FLOOR SURFACE SHALL BE OF APPROVED NON-COMBUSTIBLE MATERIAL. (R309). DUCTS PENETRATING WALLS OR CEILINGS SEPARATING THE DWELLING FROM THE GARAGE SHALL BE CONSTRUCTED OF A MIN. 26 GAGE SHEET STEEL OR APPROVED MATERIAL. (R302.5) 5. EVERY INTERIOR DOOR IN A DOORWAY THROUGH WHICH OCCUPANTS PASS SHALL HAVE A MINIMUM WIDTH OF 32". MINIMUM ROOM DIMENSIONS: (R30 & R305) 1. HABITABLE ROOMS SHALL HAVE A FLOOR AREA OF NOT LESS THAN 70 SF. 2. HABITABLE ROOMS SHALL NOT BE LESS THAN 7 FT. IN ANY HORIZONTAL DIMENSION. 3. HABITABLE SPACE AND HALLWAYS SHALL HAVE A CEILING HEIGHT OF NOT LESS THAN 7 FT. BATHROOMS, TOILET ROOMS, AND LAUNDRY ROOMS SHALL HAVE A CEILING HEIGHT OF NOT LESS THAN 6'-8". LIGHTING: (R303) ALL ROOMS REQUIRE NATURAL LIGHT BY MEANS OF EXTERIOR WINDOWS OR SKYLIGHTS MIN. 8% OF THE FLOOR AREA OF THE ROOM. VENTILATION: (R303) ALL ROOMS REQUIRE NATURAL VENTILATION BY MEANS OF OPENABLE WINDOWS MIN. % OF THE FLOOR AREA OF THE ROOM. IF LESS THAN 60" ABOVE STANDING SURFACE (R308.), WINDOWS AT SHOWERS & TUBS SHALL BE TEMPERED. SHOWER DOORS SHALL SWING OUT. NET AREA OF SHOWER RECEPTOR SHALL BE MIN. 2 SQ. IN. OF FLOOR AREA, AND ENCOMPASS 30 IN. Ø CIRCLE (PC 08.6) 6' HIGH NONABSORBENT SURFACE AT SHOWER WALLS (R307.2) SEE NOTE KITCHEN 22" X 30" ATTIC ACCESS OR LARGER. MIN 30"X30" PLATFORM. (R807.1, MC 30.) 16"X2" UNDERFLOOR ACCESS THROUGH A PERIMETER WALL (R08.) GLAZING SHALL MEET THE FOLLOWING: U-FACTOR = 0.32 MAX, SHGC MAX. GLAZING AREA LIMITS: 20% MAX OF TOTAL FLOOR AREA. 5% MAX OF THAT CAN BE WEST FACING. (CLIMATE ZONE 8, 9, 1 ONLY) OTHERWISE PROVIDE TITLE 2 ENERGY CALCULATIONS. 1/2" GYPSUM BOARD TO ROOF LINE (TABLE R302.6) UNDER-FLOOR AND ROOF VENTILATION (R08 & R806) PER LOCAL ZONING ORDINANCE 18' Min. PIPE BOLLARD OR OTHER PROTECTIVE MEASURE WHEN APPLIANCES ARE SUBJECT TO DAMAGE 3" MIN. DIA. (PC507.13) DOOR SHALL BE A SELF-CLOSING & SELF-LATCHING 1-3/8" THICK SOLID WOOD OR HONEYCOMB CORE STEEL DOOR OR 20-MIN. FIRE RATED DOOR. (R ) NOTE: THE GARAGE SHALL NOT OPEN INTO A SLEEPING ROOM. GARAGE (SEE NOTE 3) 1. UNDER-FLOOR SPACES SHALL BE VENTILATED BY OPENINGS INTO THE UNDER-FLOOR SPACE EXTERIOR WALLS. SUCH OPENINGS SHALL HAVE A NET AREA OF NOT LESS THAN 1 SQUARE FOOT FOR EACH 150 SQUARE FEET OF UNDER-FLOOR AREA. ONE VENTILATION OPENING SHALL BE LOCATED WITHIN 3-FT OF EACH CORNER OF THE BUILDING AND PROVIDE CROSS VENTILATION. VENTILATION OPENINGS SHALL BE COVERED WITH CORROSION RESISTANT MESH W/ LEAST DIMENSION NOT EXCEEDING 1/". 2. THE NET FREE VENTILATING AREA OF ENCLOSED ATTICS AND ENCLOSED RAFTER SPACES SHALL NOT BE LESS THAN 1/150 OF THE AREA OF THE SPACE VENTILATED. EXCEPT THAT REDUCTION OF TOTAL THE AREA TO 1/300 IS PERMITTED PROVIDED THAT AT LEAST 50% AND NOT MORE THAN 80% OF THE REQUIRED VENTILATING AREA IS PROVIDED BY VENTILATORS LOCATED IN THE UPPER PORTION OF THE SPACE TO BE VENTILATED AT LEAST 3- FEET ABOVE THE AVE OR CORNICE VENTS WITH THE BALANCE OF THE REQUIRED VENTILATION PROVIDED BY EAVE OR CORNICE VENTS. AS AN ALTERNATIVE, THE NEW FREE CROSS-VENTILATION AREA MAY BE REDUCED TO 1/300 WHEN A CLASS I OR CLASS II VAPOR BARRIER IS INSTALLED ON THE WARM-IN-WINTER SIDE OF THE CEILING. A MINIMUM OF 1-INCH CLEARANCE SHALL BE PROVIDED BETWEEN THE INSULATION AND ROOF SHEATHING. VER. 7.0 ( ) 7