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HomeMy WebLinkAboutDETAIL MANUALGulf�st SUPPLY & MANUFACTURING Ridge caps (pg. 9) Eave drip (pg. 8) Valleys (pg. 12) Gable rakes (pg.) 11 Wall flashin s (pgs. 10 - 1� Transition & gambre flashings (pg. 10) t 4 Corner trims (pg. 13) Door & window trims (pg. 14) Base drip (pg. 14) _.` �'»' Pipe Boot (pg. I1) Electrical Boot Reflective bubble insulation Inside Closures - -' .. �. Outside Closures -® Flex-o-vent w Profile Vent Expanding Yoam Peel and Seal Touch-up Paint S/D TEK Lap TEK Butyl Tape Titebone Woodgrip Screws TEK screws WoodZac`s screws WoodMac screws Guide to Misc. Accessories pipe boot Fits over vent and heat pipes. Available also in heat -resistant boots. - -- -- -- — --------- electrical boot _-_ -- — - ----- - ---- — - - ---- ---- ii- ----- Fits around pipes with inaccessible tops (such as weatherheads)._ outside closures Required to seal under ridge caps and transition and endwall flashings. inside closures -_ Seals under panels, particularly on the eave__ `- `_-- Profile Vent, Flex -Vent® Vented closure material surpassing many other venting _systems._ -expanding foam_ __ _Compressed adhesive foam expands_to seal between valleys and panels._ Peel and Seal® Seals hips under hip caps. Also, a general purpose sealing tape (6" wide)._ _ touch-upp--------- Hides scratches and mars encountered in installation. Over 20 colors. butyl tape _General purpose low-cost sealant, used on panel laps and under trim. _ Titebond® A superior general purpose caulk for all joints._Matches panel colors.. _�- Low profile insulation Greatly reduces radiant heat when installed under panels. Woodgrip screws__ Used in all applications attaching metal to wood: 1"_1%2", 2r/=" sizes. TEK screws Self -drilling TEK screws for metal purlins. Lap TEK screws draw together joints and attach_ trim. ZAC® screws "Lifetime" screws: 1%". V/s". threaded for wood; self -drilling available. SUPPLY & MANUFACTURING; SCANNED BY S4luc ount i) GULF RIB`" DETAIL MANUAL Figure 1 The Horseshoe Beach Gulf Coast Supply office (left) and manufacturing facility. conditions. Both panels and trim are fabricated using state-of-the-art computerized equipment found at our facilities in three locations in Florida, to assure uniformity and consistency in product manufacture. Panels are roll -formed to the lengths specified by customers in either Galvalume or any of more than twenty colors of painted 29- gauge, 26-gauge, and 24-gauge high -tensile metal, ready for either customer pickup or on -site deliv- ery (customers should call about availability of 24-gauge metal). Your Gulf Coast representative is waiting to assist you in making the best choice for your particular roofing needs. Gulf Coast's Gulf Rib' panels are fabricated from AZ-50 (painted) or AZ-55 (bare Figure 2 The 4 locations of Gulf Coast Supply. Galvalume ) grade 80 coil stock (grade 50 for 24 bare Galvalume finish is not only durable and cost effective, but offers reflectivity so valuable here in the South. The paint system employed on painted products offers optimum exterior protection plus superior t resistance to corrosion and ultraviolet radiation. While bare Galvalume carries a 25-year limited coil manufacturer's finish warranty, Figure 3 The Gulf rib pan el<-9"—►� most painted metal carries a 40-year war- ranty. Both painted and unpainted are of the The Gulf Coast Gulf Who Roofing Panel durable, economic, and attractive answer to the growing demand for metal roofing needs in Florida and southern Georgia. Extremely versatile, they are suitable for homes and businesses as well as agricultural and utility buildings Gulf Rib' panels provide a 36- inch coverage with 3/4 inch ribs on nine -inch centers, and utilize an anti -siphoning channel to provide protection from severe weather highest known quality in the industry. Gulf Coast also stocks a complete line of fasteners, sealants, and other accessories to meet every need of both the do-it-yourself homeowner and the roofing contractor. A complete line of both in -stock and custom-made flashings and trims are available in all colors as well. Gulf Coast Supply produces 29-, 26-, and 24- gaugegutters in either 5- or 6-inch widths (depth is approximately equal to width). All gutters should be ordered specific to the pitch of the roof. Downspouts are available in Yx4" (for 5- inch gutters) and 4"x4" (for larger gutters). End caps should be ordered at the same time as the gutters to assure a custom fit. Special hangers fit into the panel rib and under the gutter lip. Panels should extend no more than 1" to 1%" inches beyond the eave on which gutters are planned. lap screws Figure 21 Exposed view of gutter showing gutter hanger �-5 or 6"—+ placement, downspouts, and end caps. Hangers employ lap / - screws, and end caps are best attached with rivets. Gutter hangers fit inside panel rib and under lip ro — —'-- — —fr `7r ofguttei(applyatleast-l7Uter. <- Inner ,_: ? Outer 4- Inner -..0 one per panel) and are Inner and outer gutter sections (marked "I" and "O") attached with lap screws alternate along the eave to assure ease of application and or rivets. gutter appearance. Dos in excess of 10 feet in length must be made in 2 sections. Figure 22 Sliding door track covers fit over the door track and under the panels to hide the track, assure a neat appearance, and shed water overthe door. ® Track Covers '-1 sing door ck cover I imp cap I 1 1 I I L_ I 1 I ' j-channI GuIfC�®a"stP SUPPLY & MANUFACTURING ® Drip Cap and J-Channel ?/ Figure 19 The drip cap is commonly used to trim out the bottoms of panels over doorways and windows, and occasionally takes the place of base drip. J-channel is used to cap raw panel edges where run-off is not a problem, and is most commonly used to trim around the bottom, sides, and occasionally the top of windows and doors, and also to cap the top sides of skirting. Base Drip 00, C BD-1 1'/< Base drip DC-1 Drip cap capping the panel end ® JC-1 J-channel a m panel 7/a" z /4 ____� capping the panel edge Figure 20 Base drip seals off the bottoms of panels at the floor level, where it helps to prevent the entrance of rodents and insects, as well as a base for the setting of panels. GULFRIBn DETAIL MANUAL Installation of Panels Roof Pitch Gulf Coast roofing panels require a certain degree of pitch to ensure proper water drainage. Florida Building Code allows a minimum pitch of 2/12 for Gulf Rib® panels as long as lap screws and sealant are applied to the laps to prevent water from siphoning over the ribs (see Fig. 5 on p. 4). Lap screws and sealant are optional when the pitch is 4/12 or greater (4/12 pitch means that there is 4 inches of rise for every 12 inches running horizontally). As a general principle, the less steep the roof, and the more necessary also that sealant be used at all side -laps. Consult our representative for recommendations for your particular roof pitch, and about roofing options if you have less than a 2/12 pitch. Roof Preparation Oil -canning is a wave -like, rippled appearance extending up the length of the panel after it has been installed on the roof. Any irregularities in the roof, including uneven plywood joints, warped plywood, uneven trusses, poor application of underlayment, the use of button caps with felt paper, etc., can promote oil -canning. Care should be taken to provide a flat, uniform surface on which to attach the panels. See page 6 for more details. Roof Application Panel installation should begin at the gable end of the roof opposite the prevailing rain -bearing wind (this will provide added assurance against wind -driven rain being forced under the laps). Measure one panel width in from the roof edge. At this point chalk a line from ridge to eave. Place the leading edge of the first panel along this line. It is extremely important that this panel be laid square to the eave and ridge so that the remaining panels will line up square on the roof frame. It is wise to have a person at the eave and at the ridge to ensure that the proper panel coverage is being maintained across the roof. Also be sure that the panels are properly side -lapped (see fig. 7 on page 7). In applications where end -lapping is necessary, the upper panel on the slope should lap over the panel that is lower on the slope by about 12 inches. Lesser roof pitches require a greater amount of panel overlap. All end -lap applications should use two horizontal rows of butyl sealant tape across the panel and proper fastening to provide a maximum water seal. An overhang of 2 to 3 inches on the eave is recommended to provide a drip edge, while only 1 inch overhang is necessary where gutters are used. The open panel ribs at the eave can be sealed with inside closures. For maximum weather -tightness, a row of butyl tape can be applied above and beneath closure material. Trimming and Cutting Steel Panels The best device for cutting steel panels across the profile is either hand snips or a nibbler. Nibblers, and especially Carborundum blades on electric saws, however, do have a tendency to either leave hot metal particles that can burn paint surfaces or to leave rust marks on panels and trim. The same is true of any filings left on the roof caused by the application of screws. Care should be taken to brush all such particles from roof surfaces after application. To cut panels lengthwise: Note carefully where the panel is to be cut, and, using a straightedge, score deeply down the length of the panel with a sharp -pointed utility knife. Folding the panel along the score mark, and bending back again if necessary, should produce a clean break in the panel. CAUTION! clean all metal shavings and particles off of roof to avoid unsightly rust stains Residential Trim Seep. 12 for Siding Trims Valley - — — 40).:12)_ Roll Lite Door /TYanshig Flashing (p.10) Figure 4 Roofing trims and flashings are named by the location or function of that particular piece on the building. GUIX66a t SUPPLY & MANUFACTURING Ridge SEE 8) Panel lap detail Lap Screw\ Apply sealant y to lap overlap► ` ✓ p irlin-bearing leg deCkln Figure 5 Butyl tape or caulk is required when the roof pitch is 3/12 or less, with lap screws applied every 2 feet to maintain water -tightness of the lap. On pitches greater than 3/12, lap screws and butyl tape are optional. For more details on screws, see pgs. 6 and 7. GU'LF'RIB' DETAIL MANUAL GR-2 Outside Corner Ooo- The GR-2 Rake and Corner can be used as a gab a tnm or ca omer for metal -sided buildings.—'= As an alternative, the smaller EF-1 or the GR-1 (both on p.11) can also used as gable rakes, and the PC-5 (below)or the GR-1 as corners. Customizing rakes or corners is often necessary due to their landing on a panel rib. Both the GR-2 and the IS-2 can be ordered as custom trim items by specifying custom dimensions "a" or "b". Be sure to take into account the 1/4" "head space" when figuring custom dimensions. The PC-5 flat comer works best on smaller structures, and where the panels are running horizontally. It can be sealed with outside closures. r Figure17 When used as corner trim, the GR-2 straddles the ribs of the panels where they meet at the comer of the building. The Gulf Rib outside corner also serves as a gable rake (see below). The inside comer (IS-2) has similar dimensions but with a reverse middle bend. Figure 18 When used as a gable rake, the GR-2 runs parallel tothe ribs of the roof panel, and is attached with screws running through the ribs of upright siding. As with the EF-1 residential rake, the roof side can be sealed with butyl sealant. Z Gable Rake �i Gulf'st SUPPLY & MANUFACTURING Preformed ► Valley Install panels 2 to 4" from diverter PV-1 sty el —►� --------------- PV-2 style Two basic styles of valley are available. For custom valleys, specify dimension "a" Figure 15 Pre -formed valleys use a diverterto prevent water from rushing under panels on the opposite side, while meanwhile channeling water off the roof. Expanding foam closures are often used to assure a good seal. Gulf Coast Gulf Rib® Siding Drip Cap (p_T4) Sliding Door ie Drip (p.14) Figure 16 Common trims associated with Gulf Rib roofing panels GULF RIB"' D'ETAIL.MANUAL, Ordering Roof Panels and Screws Care should be taken to order panels of the correct length to avoid having to make corrective measures after purchase. Panel lengths should fall 2 to 3 inches short of the ridge when a vented ridge is desired, and should extend 2 to 3 inches past the cave to allow a sufficient drip edge (except as noted on pg. 3 concerning gutters). When a roof transition is involved, panels of the upper portion should be ordered short to allow placement of the transition flashing (see diagram on p.10)* The Gulf Coast sales personnel are ready to assist customers with information specific to their particular roof. Specially-washered screws applied through the flat of the metal is the most recommended method used to attach roofing panels. 1-inch screws can be used if penetration of only a/4 incb is either necessary or desired; otherwise, 1'/z inch screws are usually recommended. 2%z inch screws are also available, and are often used by those who adhere to through -the -rib fastening, and for ridge -cap application. See pages 6 and 7 for more information on screw spacing and ordering. Ordering and Applying Trim The most common flashing for metal roofing is the ridge cap, which is used at the peak of a roof where two opposing roof slopes join. Other flashings include transition flashing, end wall and sidewall flashings, and valleys (see diagram on right for application). Eave trims include gable flashing and eave drip, either of which are often applied above fascia trim. When roof pitch exceeds 5/12 (a 5 inch rise in 12 inches), the slope of the roof should be mentioned when ordering ridge caps, endwalls, and eave drip. When a steeper roof slope meets a lesser slope, both slopes should be mentioned when ordering transition flashing. At the gable edge the use of gable trim adds to the appearance of the structure and protects the fly -rafter, and sidewall flashing is used where the side of a panel butts up against an adjacent wall. In either case, the installer should be careful to seal between the gable rake or sidewall and panel with butyl sealant tare, and to fasten the rake every 6" to 12" up the slope of the roof with the appropriate screws. If cave drip is used on the gable, the number of 90 degree cave drip should be specified separately from that used on the drip edge when ordering. To prevent penetration of water, insects, and debris at the ridge, outside closures should be inserted between the ridge cap and the top end of the panel. Screws are applied through the ridge cap, closure, and rib in at least every other rib of the panels. At least a 1'/2" (or preferably 2%z") screw should be used for attaching ridge caps. Self -drilling lap screws can also be used to attach ridge caps. Keep Materials Dry! Paint and finishes of Gulf Coast panels and trim are designed to withstand severe rain and wet weather conditions. Neither paint, galvanized, or Galvalume finishes, however, are designed to be in continuous contact with water for long periods of time. Damage will result if uninstalled panels or trim are allowed to remain wet in storage. Be sure to store material that will not be installed immediately in a dry location. Wet material should be air-dried and re -stacked if installation is not planned right away. \ri�a `k ) GULF RIB'" DETAIL MANUAL.IMEW, How to Figure and Apply Screws Y 12 inch 18 inch 24 incl 50 270 j 180 135 Gulf Coast Supply -carries -screws in 3 different-lengths:-Linch 1'/z �_ 10__0 540 } 360 270 inch, and 2 %z inch. 1-inch screws will barely penetrate a lx4, but the Y o 200 1080-,-720--540- 1'/z inch are the best all-purpose size. 11/s- or 2'/2-inch screws are g 300 1620 ' 1080 ; 810 necessary for attaching ridge caps. The table on the right can be .� 400 500 2160 2700 1440 +_ 1800 1080 1350 used to figure approximate quantities of screws for various purlin -6001 3240 1620 spacings and sizes of roofs. For 2-foot spacing between rows of a o 7001 3780 i-2160 i 2520 1890 screws, multiply the total linear feet of metal times 2.7 800 4320 2880 ; 2160 Example: your order is 1250 feet of Gulf Rib roofing. 900 _ 4860 3240 2430 1250 x 2.7 = 3375 screws 0° a 1000 5400 3600 ^2 700 11001 5940 1 3960, 29 00 Please confirm all estimates with your Gulf Coast representative when 1200 6480 1 4320, 3240 you placed your order. ! -Ffigure 6 Gulf Rih panel screw Codes allow re -roofing over shingles without the use of battens calculation chart provided the roof has been checked by a licensed roofing. contractor to insure levelness and pullout integrity. Gulf Rib metal roofing can be separated from the moisture barrier by minimum, nominal I "x3" yellow pine battens spaced on maximum 24"centers, or according to ASCE calculations where applicable. Since direct contact between pressure treated lumber and metal roofing must be avoided in order to prevent potential corrosion, Gulf Coast Supply sells only untreated battens. CAUTION: Battens must be fastened to the roof deck with minimum #6 screws at 12" on -center, or two minimum 8d common or pneumatic nails spaced 8" on -center, or one every 4" on -center (or by applicable calculations according to ASCE 7-98). Battens must be installed to support the entire width and length of ridge, eave, hip, valley, and gable -end trims. For solid decking, at least 15/32-inch structural plywood supported on rafters at a maximum of 24" on center is required. If care is taken, metal roofing application can be aided by pre -drilling panels, allowing screws to go quickly and accurately into the desired spacing. Pre -drilling will work provided that pilot holes are placed accurately in the proper locations on panels. Purlin spacing must be uniform and.carefully measured. For panel lap details, see Figure 5 on page 4. Gulf Coast Policies Delivery policy Delivery charges apply to all orders where delivery is requested. Please consult your Gulf Coast sales department for details. Sales tax All orders picked up at Gulf Coast Supply, and all orders delivered within the state of Florida, are subject to state sales tax. Tax exemptions should be verified prior to delivery or customer pickup. Warrantied products A 40 year warranty applies to most material* manufactured from painted coil stock, and a 25-year warranty to Galvalume material. Ask for details. Indemnity All prices and designs are subject to change without notice Disclaimer While we have made every attempt at accuracy in this manual, we are not responsible for typographic, printing, or technical errors. Oil Canning —a repeating, wave -like appearance in the length of the panel —is a common and often unavoidable phenomenon in metal panels like Gulf Rib roofing that have large, flat areas within the panel. It is therefore not a defect, nor a cause for rejection. See p. 3 for details on how to avoid oil -canning. Return policy All panel orders and special order (non -stock) trims are considered the property of the customer and non- refundable once they are manufactured. Standard trim and accessories are refundable providing they are returned in a clean, resalable condition. For details, go to www.gulfcoastsupply.com and click on "No Hassle Return Policy" at bottom of page, or call Gulf Coast Supply to ask specific questions about returns. GULF RIBS' DETAIL MANUAL Gable Flashing Oo- 311 L_ -- - - - - 3/4" 5" 311 EF-1 style 7/16" Custom trim —specify a custom R length fororb. Standard dimensions — a = 3" b=3" GR-1 style Custom trim —specify a custom -"f length for a or b. b Standard dimensions — a = 2 N b =23/8" Figure 13 Gable flashing is used to trim the edge of the roofing panel at the gable end of the roof. It should match the eave drip that extends along the drip edge of the roof. If the panel is allowed to hang over the gable end, eave drip can be used instead. Butyl tape between the trim and panel eliminates leaks. ® Side -wall Flashing 3" , caulk (Solar SeaP recommended) caulk edge (order SW-1C) (used if sidewall not covered by siding) ' 511 Butyl tape Figure 14 Sidewall flashing is applied when the side of the SW-1 roof butts up against an adjacent wall. The wall -side ofthe flashing can either be covered over with siding or sealed Custom trim —specify a custom with caulk (order SW -IC). Butyl tape should be applied length for a or b. 1 �� where the "foot" ofthe flashing attaches tothe roof. Standard dimensions — a = 3" b=3" ;) GULF RIB'" DETAIL MANUAL �. Figure 11 As with the ridge cap, the ENDWALL FLASHING above is sealed using outside closures. Use EW-2 hemmed endwall when comering endwalls with sidewall flashing, such as with dormers or chimneys. For custom end -walls, specify roofpitch and dimensions "a" and "b", Transition Flashing The TRANSITION FLASHING prevents leakage at the point where two different roof pitches meet. It must be sealed on the lower side with outside closures, and can be sealed underneath the upper panels with inside closures. The similar GAMBREL FLASHING is used where the lower pitch is steeper than the upper. TF-I Transition Flashing t End -wall Flashing End -wall flashing is applied where the upward slope of a roof meets a wall. The wall side of the flashing can be covered with siding or counter -flashing, and outside closures are — c-aulk(Solar Seal recommended) caulk edge (order EW-1C) 3„ (used if endwall not covered by siding) 1 EW-1 Stepped b Endwall �l I� Figure 12 The transition flashing (above) and the GF-1 gambrel flashing (right) provide a For custom transition flashing specify the pitches continuous drainage where two of the two roof slopes and, if necessary, dimensions slopes meet. Both seal with "a" and "b". outside closures on the lower side. necessary to seal between the flashing and the panel. Roof slope should be mentioned if roof exceeds 5/12 pitch. IEW-2 Hemmed b � Endwall 1 I \a a = 4'/2" b=3" \ � GULF'RIB'" D:ET.AILMANUAL Gulf Coast Gulf Rib® flooring Panels Fastening Schedule for Various Wind Speeds — minimum 2:12 roof pitch Wind Speed Zone 130 MPH 140 MPH 160 MPH 160 MPH Roof Fastener Fastener Size Attaching to: On Center On Center On Center On Center Zone Type Spacing Spacing Spacing- - Spacing Zone 1 'Woodgrip® or #9-15 x 1% min.15132 24" 24" 24" 24" WoodZace plywood Type.1 Type 1 Type 1 Type 1 Zone 2 Woodgrip® #9-15 x 1'/, min.15/32 24" 24" 24" 24" woodzac® plywood Type 1 Type 1 Type 1 Type 2 Zone 3 Woodgrip® #9-15 x 1'h min.15132 24" 24" 24" 24" Wo dzac® plywood I Type 2 Type 2 Type 2 Type 2 Fastener pattern Type 1 }/t Type 2 I Zone 2 a ...................... I .......................................... ... I _T_ .......... :...... .................................................:... ------------- ----Ridge -=------------ — lt..................................................................:... Zone 1 Fastener pattern Fastener patterns Type 1 and Type 2 are shown at left, row spacings are shown in the table above, and roof zones are displayed on left below. Figure 7 shows a simple illustration of the patterns. Note that fastener pattern Type 2 is required at top, bottom, and end laps of each panel, as well as in additional areas according to which roof zone the fasteners fall in. Each "zone" of the roof has its own screw requirements. Dimension a is defined as 10% of the minimum width of the building, or 40% of the mean height of the roof, whichever is smaller; however, a cannot be less than either 4% of the minimum width of the building, or 3 feet. Figure 7 Screws should be placed on both sides of the ribs at both eave and ridge, and on the overlap side of any panel laps. \' /, ' ).GULF RIB" DETAIL MANUAL � and inside closure Figure 8 Eave drip and fascia give a finished look along the drip eave of the house, as well as providing protection for the materials they cover. The eave drip should completely cover the top edge of the fascia. Inside closures, which seal off the open ribs of the panels, are optional. ® Eave Drip &_ _Fascia �--3 o_0 1 T FHA Style ED-3 Style 2 N" Eave drip Eave drip y � 7/16 I For custom eave drip, specify the Eave tlrip amount of the eave that will be covered (dimension "a"), and, for steeper roofs, specify pitch . If Fascia a fascia is desired, be sure that the 1 dimension you order will be ,I b � I hidden by the eave drip. Summary of Stock I)rims and Flashings item special order information Ridge caps (RC-2) specify pitch if less than 3/12 or greater than 6112. Also available in larger widths. Closures recommended. Eave drip (FHA, ED-3)' 2 common styles. FHA style is pre -pitched for 3/12 to 6/12 roofs. For appearance or ease of application, order by either specific pitch or as gable trim (901). Gable flashings Residential (EF-1), large (GR-2), and small (GR-1) rakes available. Use butyl sealant between rake and panel. Valleys (PV-1) specify pitch if greater than 7/12. Seal with universal foam closure material. Open -hemmed valleys (PV-2) aid water -tightness. Sidewall (SW-1) Use butyl sealant between sidewall flashing and panel. Endwall (EW-1) Specify pitch if greater than 5/12. Seal with outside closures. Transition flashing Specify pitches of both roofs. Seal lower slope using outside closures and, If desired, inside closures on upper slope. GULF RIB' DETAIL MANUAL Ridge Cap , The Rid e Cap is used to seal the point at which two upward slopes meet. This can be both along the ridge of the roof as well as a covering for a hip. Either woodgrip or self -drilling lap TEK screws are applied through the ribs of the metal. Since debris, insects, and blowing rain can find easy access under the ridge cap, closures .are required to either completely or partially seal the opening. Closures under ridge caps come in 3 types: solid, vented, and hip tape. Figure 9 Ridge cap showing outside closure (left) and profile vent Solid closures ("Outside Closures") are (right). the same width as the panels. They lock together in a row placed directly under the screws that attach the ridge cap, and form a solid, water -right, air -right barrier. Profile Vent® comes in 50 foot rolls, is 3 inches wide, and forms a water - retardant, insect resistant barrier that allows hot air to escape from the attic, and is superior to many more elaborate and expensive vent systems. Any length may be ordered. Hip closure tape (Peel and Seal is a sticky, adhesive -backed metallic tape that seals the hip roof. It is 6 inches wide and comes in 33'/2 foot rolls. Because it must be conformed to the rise and fall of the panel ridges, approximately 10%extra may be needed beyond the length of the hip being covered. Outside closure \✓ Lap or 2V' Woodgrip *---► screw required Profile Venta or Versa -Vent% RC-2 Standard 12-inch Ridge Caps are strong, economical and adequate for most of your roofing needs C RC-1 style 12-inch Ridge Caps are also available in custom widths Figure 10 Pipe Boots provide a water -tight seal around roof vents and come in a variety of sizes. They seal with caulk and conform to the shape of the panel ribs. a� R 2C style over -sized ridge caps are available with 18-inch coverage, or as a custom trim item in total widths (2 times "a") of 14-, 16-, 18-, 20-, 22-, and 24-inch