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HomeMy WebLinkAboutAPPROVED RAS 150 Prescriptive BURloafing Application Standard (RAS) No. 150 Prescriptive Bur Requirements 1.1 This application standard shall be used where the authority having jurisdiction has adopted its use, and in accordance with the provisions of this code_ . Definitions .1 For definitions of terms used in this application standard, refer to ASTM D1079 and the Florida Building Code. Building, t Built-up and Prepared Roof Covering Application 3.0 General .1 OECD PRE PA T10 N : Before starting the roof covering; 1.1 All roof decks shall be broom -cleared and dry. 3.1.2 Where practicable, eaves; parapetwalls; vertical galls; penthouses and similar structures above the roof level shall have been completed. 3.1.3 Cant strips, inhere provided, shall extend at least three inches (3 in.) up vertical surfaces. .1.4 All eaves hall provide firm, nail able backing for the secure attachment of gravel stops and eave and gable drip. 3,1,5 All precast and prestressed concrete roof components shall be provided with insulation, or other leveling fill, where such component edges are more than one-half inch � 1/ in.) from being flush. 3.2 ATTACHMENT., Ali roof coverings shall be attached to the various types of decks by mopped -on adhesives or b mechanical fastening as set forth herein, or by ether approved materials or methods. . ADHESIVES; . .1 Bituminous compounds shall be asphaMit (AST(ASTM D312), coal tar pitch (AST(ASTM D450), modified bitumen, or cold -applied roofing cement (ASTIVI D4586 or ASTIR D 019, Type 111). 3.3.2 Hot asphalt shall be a ppi i ed in a quantity not less than 25 pounds plus or minus 15 percent per roofing square per ply and 60 pounds plus or minus 20 percent per square for flood coats and at a temperature recommended by the manufacturer for the system being installed. However, kettle or tanker temperature should not exceed the following, Type I Asphalt- 475T Type III & IV Asphalt- 5 S `F HOTS. Asphalt can be heated to within 'F below the actual flash point, but this temperature lim-tation should never be exceeded. 3.3.3 Coal tar pitch shell be applied in a quantity not less than 25 pounds plus or minus 15 percent per roofing square per ply and 70 pounds plus or minus 0 percent per square for flood coats. and at a temperature of not less then 275 nor rniore than 50° f (350 to 40 ' F in the kettle)- . .4 Where roof incline exoeeds two inches (2 in.) per feet, bituminous compounds shell be steep asphalt Type I I I or Type I, NOTE; Coal tar pitch not to exceed a slope of ono -half in to (112 in.) per foot with organic felts, if using glass fetts or tar coated felts, slope not to exceed one -quarter inch (1 /4 irk.) per foot. - 15 Adhesive compounds other than bitumen may be applied subject to manufacturer's specifications. 4. BUILT-UP ROOF COVERING: 4,1 Materials.- All materials used in the assembly of fire -retardant and ordinary built -rip coverings shall bear the label of an approved agency and be compatible with Class A, Class B, or Class C roofing. Material shall be delivered in original packaging bearing the manufacturer Is labels. 4.2 ANCHOR SHEET: The anchor sheet, as defined herein, shall be a minimum one # 0 felt lapped two inches (2 in.) and tumed up vertical surfaces a minimum of four inches (4 in.) and secured as set forth herein. 4.3 WOOD DECKS-. 4. .1 Fasteners securing the anchor sheet to nominal one inch (1 in,) lumber or to wood based structural -use panels three-quarters inch (/4 in.) or rnDre in thickness shall be noncorrosive smooth shank nails with a shank diameter of a minimum of 0.11 inches or 11 gage, heads not less than three -eighths Inches (318 in.) (0.375) diameter and not less than one inch (1 in.) In length ur non -corrosive 12 gage wire ring -sharked nails having not cress than 20 rings per inch3 not less than one inch (1 ire,) in length with heads not less than three -eighths inch (3/8 in.) ire diameter. 4.3.2 Fasteners securing the anchor sheet to wood based structural -use panels less than throe -quarters inch (3/, in.) to thickness shall be non corrosive smooth shank nails w[th a shank diameter of a minimum of 0. 118 inches or eleven (11) gager heads not less than three -eighths inch (3/5 in.) (0. 375 in.) diameter and not lass in length than will penetrate such wood based structural -use panels plus three -sixteenth inch (3116 Mfg.), or noncorrosive 12 gage wire ring-shanked nails having not less than 20 rings per inch, heeds not less than three -eighths ire h ( /.B in.) diameter and not less in length than will penetrate such wood based structural -use panels plus three- ixt nth inch (/, I& in.). 4 _ 3 _ 3 Such fasteners shall be appi led th rough fin -caps not less tha n one and five -eighths inches (15/8 in.) nor more than two ro be (2 in.) in diameter and of not less than -gage sheet metal, 4. .4 Spacing of such fasteners along the laps of sheets and bath gays In the field between laps shall comply with Table 1, based upon height above grade. 4-3-5 Inhere the architectural appearance is to be preserved from below, anchor sheet shall be secured in accordance with Section 1 b1 .-. 4.3.6 Other sob -deck systems may use the spacing shown in Table 1 provided each fastener has the required withdrawal load In the particular substrate for which the fastener is designed. 4. .7 Sheathing paper shall be applied on such decks where anchor sheets are pitch -tarred felts only and shall not he required under asphalt felts. 4.4 OTHER NAILABLE DECKS-. Poured gypsum, precast g R��m p1arek , poured VarmicuRe and Perlite (light --weight, insulating concrete), as well as foamed cellular concrete a structural good -fiber used as roof decking are considered nailable and anchor ets shall be attached as follows: N. 4.4.9 Poured gypsum and past gypsum planks; Use mechanical fasteners providing equal withdrawal resistance when spaced as set forth de_ in Table%foam(Ads 4.4. Poured Vermiculite, Pedite, ular concrete, and other light -weight, insulating concrete. Use only mechanical fasteners providing resistance to u-PQ net less than these shown in Table 1. r 4.4.3 Structural wood fiber unit Lase mechanical fasteners specified by the deck manufacturer, or after all joints have been stripped with sic irvch (6 in.) wide felt applied with approved cold adhesive, the anchor sheet may be solid mopped to such decks. 4.5 NON-NAILABLE DECKS: Poured concrete and precast deck units are considered non-nailahle and anchor sheets shall be fastened as follo 4-5-1 Such decks shall be \back a roved asphalt primer applied at the rate of one and one third (11 / ) gallons per roofing squareon d decks but held back four inches �4 in.) from precast unit joints. 4_ _ Strip or solid mop, hr inches (4 in.) from precast unit joints, using dead level asphalt or coal tar pitchy as the adhesive unless otherwise spi6qified on the plans and permit and embed anchor sheet firmly in the hot bitumen rapping each sheet four inches (4 ire. 1\ 4.5.3 Where the incline of such decks exceeds thre ~aches (3 in.) per foot, anchor sheets shall, in addition to mopping, he mechanically fastened to wood strips sP ed not more than 24 inches apart, cast into such decks, 4L5.4 Such wood strips shall be not less than a nominal one by two inches (1 jn. x 2 In.), pressure treated with approved preservative, charnfered or otherwise secured flash with the deck surface. 4.5.5 Anchor sheets shall he attached to such wood strips with three-quarter inch (314 in.) long fasteners applied through tin caps and spaced as set forth herein. 4.5L6 Anchor sheet attachment shall satisfy the resistance to uplift requirements of Section 4.3.6 herein. 4.6 METAL KS: Metal decks shall be covered with mechanically fastened roof insulation. 4.7 OTHE D6Ec : Attachment of the anchor sheet to decks other than those specifically provided for herein shall be as approved t e building official. 4.8 ADDITIONAL SHEETS. 4. .1 Each additional sheet above the anchor sheet shall be lapped a minimum of two inches (2 ire,) over the preceding sheet and shall be thoroughly mopped between sheets with a bituminous compound, or other approved adhesive providing equivalent bond, so that in no place felt touches felt, 4.8-2 Sheets shall be embedded without wrinkles or buckles. 4.8.3 Each sheet, like the anchor sheet, shall be turned up vertical surfaces a minimum of four inches (4 in.). 4.8.4 (aa) Polymer modified bitumen membranes shall be permitted to be applied as a single ply over a mechanically fastened anchor sheet without additional plies when-e slopes exceed one eighth inch (1/8 in.) per foot. n additional ply is required for slopes less than 118 in. per foot. Slope requirement applies to new roofs, recover roofs and rercofs- 4.8.5 Poiymer modified bitumen memo -raves shall not be applied to slopes a ceed�ng three inches ( in.) per foot. At slopes exceeding one inch (I in.) per foot, they shall be backnailed four inches (4 in.) from the upper edge at maximum twenty-four inches (4 in.) on center- 4.8.6 Polymer modified bitumen shall be applied utilizing hot or cold adhesives as specified in Section 3.2. 4.9 FELT FLASHING& 4.9.1 Flashing used in the construction of built-up roof coverings shall be carried over cant strips, where provided, and turned up all walls and other vertical surfaces a minimum of eight inches (8 in.) and maximum of twenty four inches (4 ire.), 1,2 Each layer of flashing shall be uniformly mopped with hot asphalt applied in a quantity not lass than pounds Cequivalent ns or minus 1 percent per roofing square for each mopping, or attached with approved cold adhesive provid ing bond. 4.9.3 Flashing turned up vertical surfaces shall be not less than one # 0 felt starting four inches (4 in.) out frorn the cant strip and carried up such vertical surfaces not less than sic inches (6 ire.), and one mineral surfaced felt starting six inches (6 in.) out from the cant strip and -carried up a minimum of eight inches (8 in.) above the top of the cart. 4. .4 Such flashing shall be fastened to the wall one and one-half inches (111 in.) down from the upper edge every six inches (6 ire.) after which the top edge shall be finished with a three 'In h (3 ire.) strip of membrane sat in roofing cement (A TM D458 ). 4.10 VALLEYS: 4,10,1 VaIIeys shall be metal, as set forth in Section 15 17.6, Florida Building Code. Building. 4.11 PARAPET WALLS. Built-up roof covering felts shall not wrap over walls more than 24 in. in height above the deck and, where wrapped, shall be applied as V loves= 4.11.1 Fleshing turned up vertical surfaces shall be not less than one ##30 felt starting four inches (4 ire.) out frm the ant trip and carried op the face over the tap of the parapet, and one mineral Surfaced rolled roofing ( TM D 4 ) starting six inches (8 in.) out from the cant strip and carried up and over the parapet to within three inches (3 ire.) of the outside ectge and fastened six inches (6 in.) on center, 4.11.2 The resulting edge shall therti be finished with either a three itch (3 ire.) strip of membrane set in roofing camart (A TI I D4588) and painted with aluminum paint or coping installed in accordance with Section 1517-6 of the Florida BoYding Code. Building, 4.12 INSULATION., Roof insulation may be applied under Gr over an anchor sheet and, where provided shall be attached as set forth 0 Section 5 herein. 4.13 SURFACING: 4.1 11 Mineral surfaced roofing shall be applied on inclines greater than one-half inch (1 /2 in .) per foot and shall be applied only over anchor sheets and mopped in as provided in Section 4.8 herein. On inclines five inches (5 in.) or more per foot, such caps shall be backnailed 18 inches on center, .1 . Cap -surfacing with smooth or mineral surfaced felts of glass, or modified biturnen of SIBS shall not be li�-iRi IT e requirements and shall be permitted to consist of one Layer of mineral surfaced fiberglass felt. �.� - 4.13.3 COATINGS 4.13.3.1 Coatings shall be applied no later than 60 days after installation of membrane. Surface shall be clear and dry when coating is pplied. Roof to be coated shall not be glaze coated. Coatings shall be applied in a uniform coverage with no phut �i through. 4.1 3.3.2 Aluminum pigmente 'I oati ngs conforming to ASTM D2824, Type I or III shall he applied at a minimum rate of 1.5 gallons per 'MQ square feet. 4.13.3.3 Emulsion coatings conforming to ASTM D 1227, Type III or IV shall be applied at the minimum rate of gallons per 1GO square feet. 4.1 33.4 Acrylic coatings conforming to ASTM 06083 shall not be applied on slopes less than 1/4 in. per foot, and when used, shall be applied at the rate recommended by the coating manufacturer_ . ROOF INSULATION .1 Application: Roof insulation shall provide an accep abi ase for built-up or polymer -modified bitumen roof coverings, or shall become a part of such roof coverings as foil 5.1.1 Ov8r Wood Decks- Roof in ulation shall ba mech niically fa tensed d iractly to wood d8cks or shall be sd idly mopped over an anchor sheet as set forth in Section 4.%ereirn,- .1. ver Other ailable Decks. To reduce f�1�i tur abn from the deck and preserve the insulating effectiveness, roof insulation shall be applied over an anchor sleet. 5. I . 3 I nsulation may be ful ler mopped to a re a nchor sheet on a va idable deck without any fasteners in the insulation. 5.1.4 Over Non na ii able Decks-. 5.1.4.1 Roof insulation shall be solid -mopped as provided in Sections 4.5 and 4.6 herein for anchor sheet attachment to nonnallable roof decks. 5-1.4.2 Insulation used over structural or precast wncrete deck shall be a maximum of 4' x 4' and fully mopped to the deck. 5.1.4.3 Over metal deers, roof insulation shall be nnec-hanically attached per Table 2. 5.1.5 Over Anchor Sheet; Roof insulation applied over anchor sheets, attacked as set forth in Section 4 herein shall be solid -mopped in as provided in Section 8 herein. 5.1.6 Under Anchor Sheet. 5.1a .1 where more than one layer of roof i sulation provided, each successive iayer shall be solid -mopped in and all joints shall be staggered. 5.1 .6.2 Anchor sheets applied over such instla ors shall be solid -mopped thereto, or mechanically fastened through the insulation to nailable decks with approved fasteners spaced as set forth in Table 1 and the mechanical fastening of the insulation may be omitted. 5.1.6.3 Additional built-up roofing adore the anchor sheet shall be mopped in place as provided in Section 4.8 herein. 5.1.6.4 Attachment of other roof coverings over roof insulation shall comply with the specific provisions set forth in this F, . Roof Incline: 1 Roof insulation applied to roof with inclines of 3 or more inches per foot (I inch per foot on steel decks) shali be nailed, screwed or bolted through tin -caps spaced net more than 12 inches on centers both ways- 6.2 Only ASTM D312 Type III or N asphalt shall be used on such applications, 7. Taper Retarders: here vapor retarders are specified, they shall be as follows: 7.1 Over wood and other nailable decks, vapor retarders shall be not less than two #15 felts lapped 19 inches, or one # 0 foft lapped 4 inches, solidly mopped to anchor shoot. 7.2 Over nonnailable decks, gaper retarders shall be net lass than two #15 pound felts, lapped 19 inches, shingled in and solidly mopped with hot bitumen. Mop p 1 ng : Solid mopping shall be hot bitumen applied in a quantity of not lass than 25 pounds per roofing square at temperatures as set torch in Section 3.3 and roof insulation shall be laid with staggered Joints and pressed firmly into position while such mopping is [lot. TABLE 1 (3) FOR MINIMUM BASE SHEET (:5� 1 LAYER, TYPE 0, A TM 0226 - TYPE II � Mean R f Fa:stenGng Pattern Height (Ftj Perimeter Edge (2) Field (4) D-30 i n _ , 2 roars 6 i n _ midsheet 0 in _ @ I a ps, rc�rs @ 1 i n. rn idsh eet 40 6 gin_ kaPs, rDws 6 in. rnidsheet 6 Pn_ laps. 2 re s @ 9 in. midsheet FOR MINIMUM BASE SHEET 1 LAYER, TYPE # 3, A TM 02626 - TYPE 1 �--� Mean Roof Fastening Pattern He ig h1t (Ft.) �2) F rek� (4 ) ID- 0 12 in. laps, 2 rows 15 in. rrirdsheet 12 1 n @ taps, rows @ 18 in_ mid sheet 40 12 in. laps. 2 roars @ 12 irt. midsheet 12 in_ @ laps. 2 roars @ 18 in_ midsheet FOOTNOTES: (1) See section 4 for fasteners. Perimeter edige is m ea u r-ed from all roof edges and each side of ridge as follows - The smasher of 0,10 x minimurn bulking width or 0.40 x mean roof height, gut not less than 0_04 x minimum building width or feet. () This table applies to roof slopes up to three inches (3 in.) per twelve inches (12 in.) (Maximum) (4) Flows of fasteners, midsheet, shall be a ve rrly spaced across width of sheet and staggered along length of sheet. (5) Patterns shown requife a minimuran withdra aI capacity of 341b per fastsryer (unfactored). (6) Pa tte rn s s hown requ i.re a mil n i1mum withd ra a I ca pa-c4 of 6 71 b pe r faste rye r (u nfactored ). TABLE 2 MECFLAN I ALLY FA TE ED INSU LATION FOR BUILDINGS 40 FEET OR LESS 14 HEIGMT FASTENERS PER BOARO' 5' 6) BOARD SIZE FIELO PERIMETER(2) CORNEFB I") WOOD FIBERBOARD x 4 1 fn 'nimum 2 40) c x4 7 Inch fT iini rn * I 4 $ 1 inch rn1r31mum\ 6 r 12 104; FIBERGLASS I'll 4 x 4314 inch rnini murn 4 x 4 1.5 ini:�h minimum f 4 c PERUTE 2 x 4 1 inch minirnum 4 I OCYAN U RATE . 4 x 4 1.3 inGh mirrimum 5 i 4 x 4 1-5 inch minimurn 4 8 FOOTNOTES (1) Minimum 3-inrh prates rust be used. () Perimeter- Defined as the first board or a minimum of 4 feet from the roof edge. () Corners: Defined as 8 feet in firom each side. (4) i f th e bui id ing h-as pa rapet gall s 36 inches o r hig her a roe, n d the a nti re roof pe rim eter. u se t a eau m b e r of fasten ers for th a pe ri mete r. (5) Wood end Steel decks use a mintmr,m 91 screw and penetrate through the der,k a M1nimurn of 1i2 inch, (6) The -installation of Polymer Modified Bitumen as a single -ply directly applied over mechanically fastened insulation reguifie:5 I)UBLE the amount of fasteners in the field. perimeter and corners.