Round and Oval Type B GasVent Systems for use with natural as or liquid propane category I and draft hood equipped appliances and appliances listed to use Type B Gas Vent.
A MAJOR CAUSE OF VENT RELATED FIRES IS FAILURE TO MAINTAIN REQUIRED CLEARANCES (AIR SPACES) TO COMBUSTIBLE MATERIALS. IT IS OF THE UTMOST IMPORTANCE THAT TYPE B GAS VENT BE INSTALLED ONLY IN ACCORDANCE WITH THESE INSTRUCTIONS. Dear Customer, Installer, or End User: I welcome any comments regarding matters pertaining to our Simpson Dura-Vent products. I welcome any ideas, input or complaints and I’ll make sure that someone responds directly back to you. Send your emails to: president@duravent.
CONTENTS Type B Gas Vent Type B Gas Vent Round B Vent, General Information, Planning . . . . . . . . . . . . . . . . . . . . . . . . 4 Steps for Typical Installations . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .7 Bucket Support . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. . 11 Combination Cap . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
ROUND B VENT GENERAL INFORMATION Type B Gas Vents are for venting listed Natural Gas or Liquid Propane Category I appliances only. The appliances listed below typically (but not always) use Type B vent systems.
HIGH WIND CAP DURACAP TOP DOTTED L INES SHOW POSSIBLE OFFSET IN ATTIC SPACE STOR M COLLAR SEE TABLE 2 FLASHING CEILING SUPPORT / FIRESTOP TOTA L VENT HEIGHT 90° ADJUSTABLE ELBOW B-VENT TEE B-VENT PIPE WATER HEATER CONNECTOR RISE FIRESTOP SPACE R 1 INCH MINIMUM CLEARANCE (ALL S IDES) FURNACE CONNECTOR RISE INCREASER WATER HEATER WITH D RAFT H OOD B-VENT FAN ASSISTED FURNACE ENCLOSURE 1 INCH MINIMUM CLEARANCE (ALL S IDES) LATERAL Figure 2 CEILING SUPPORT / FIRESTOP VENT C ONNECTS TO APPLIAN
TABLE 1 B-VENT WYE B-VENT USED AS CONNECTOR 45º / 60º ADJUSTABLE ELBOW FURNACE CONNECTOR RISE FAN ASSISTED FURNACE 1 INCH MINIMUM CLEARANCE (ALL SIDES) TOTAL VENT HEIGHT WATER HEATER CONNECTOR RISE DURA-CONNECT FLEXIBLE SINGLE WALL CONNECTOR WATER HEATER WITH DRAFT HOOD PIPE SIzE STOCk FRAMED INSIDE NUMBER DIMENSIONS (x & Y) OF CEILING FIG.
appliance installation instructions and any other applicable reference material determine the optimum location for the appliance(s). 2. Penetration Point. Locate and mark the center of the penetration point through the ceiling or the wall. Refer to Step 3 or 4, as appropriate. 3. Ceiling Support. For a ceiling supported system, install the Square Firestop/Support as shown in Figures 6, 7, and 8. The Firestop Support must be framed in and the dimensions are shown in Table 1 and shown in Figure 4.
STEP 2 STEP 1 STEP 3 Figure 9 WALL STRAPS EXISTING STRUCTURE 1 INCH MINIMUM CLEARANCE TO COMBUSTIBLES AT ALL POINTS 45º / 60º ELBOW WALL STRAP ELBOW GORES CEILING SUPPORT Figure 10 8 exhaust flow. For ceiling supported installations, place a Pipe Section, or assembled Pipe Sections, through the hole in the Square Firestop Support, and tighten the Clamp. The Clamp will rest inside the Ceiling Support, and prevent the Pipe Sections from dropping down.
the system, as well as burns. Figure 1 shows a system which passes through an occupied second floor. Simpson Dura-Vent does not recommend installation of B-Vent Pipe on the outside wall of a building, particularly in cold climates. If it is necessary to do this, enclose the outside portion of the system in a chase, as shown in Figure 11. Consult the Local Authority prior to construction. Note that the enclosure requires an access door for inspection and maintenance purposes. 10. Terminations.
TABLE 2 gas vent systems using vent caps listed by underwriters labroratories may terminate in accordance with this vent termination table ROOF PITCH Figure 13 CONTINUATION OF B-VENT B-VENT BUCKET SUPPORT RAFTER 16 OR 24 INCHES O.C. NAIL HERE B-VENT MUST EXTEND A MINIMUM OF 1" BELOW THE FINISHED CEILING CEILING SINGLE-WALL CONNECTOR (DURA-CONNECT) Figure 14 that all joints are secure, the system is properly supported, and is mechanically sound.
B-Vent Cap and Flashing, as one lightweight unit. The two basic components and the assembled unit are shown in Figure 15. The Combination Cap is designed to accommodate roof pitches from flat to 6/12, and is available for 3” through 6” diameter B-Vent pipe. 2. Location. Locate the point in the underside of the roof where the system is to penetrate, using a plumb bob or level. 3. Hole.
SHEET METAL SCREW 1/4 INCH LONG DRILL 1/8 INCH DIAMETER HOLE. DO NOT PENETRATE INNER LINER Figure 19 Figure 20 secured by using sheet metal screws at the joint where the male and female parts overlap, provided that the screws DO NOT penetrate the inner liner as shown in Figure 19. One screw per joint is normally sufficient. Use #8 Pan Head sheet metal screws which are no longer than 1/4 inch. Wall Straps must be used to support each elbow (Figure 10).
Adaptor as shown in Figure 22, insuring that the inner liner of the adaptor is outside the inner liner of the existing pipe. Push the adaptor as far up as it will go, and tighten the locking bolt until the connection is snug. 3. Extending an Existing Competitors System.
B C 15 INCHES A Figure 25 DRAFT HOOD CONNECTOR Figure 26 14 be rigid B-Vent Pipe Sections. For each pipe joint, subtract 1-1/2 inches. (c). Connector. Read the appliance manufacturer’s instructions for connecting the Flex Pipe to the appliance. In most cases, a Draft Hood Connector will be required as shown in Figure 26. If you are not sure, contact the appliance manufacturer for clarification.
Pipe Section even with the top of the masonry surface. If the top of the pipe is near a steep roof (more than 7/12 pitch) ,use the height as stated in Table 2. (g). Flashing. Bend and trim the base of the Tall Cone Flashing so it fits onto the top of the masonry chimney. Use masonry anchors and non-hardening sealant to secure the flashing to the masonry (Figure 28). (h). Storm Collar. Slide the Storm Collar over the pipe down to top of the Flashing.
STORM COLLAR WITH SCREWS TEE OPTIONAL HIGH WIND CAP FLASHING TRIM COLLAR DRAFT HOOD CONNECTOR (IF REQUIRED) GAS APPLIANCE Figure 30 CERAMIC FIBER INSULATION Figure 31 16 through and hold the Tee, while connecting the horizontal Pipe Section. An alternate procedure is to make the hole only large enough for the Pipe Section to pass through, and construct an access gate on the other side of the masonry chimney. Do not mortar directly to the pipe, but use a Mortar Sleeve instead. (c). Tee.
(h). Horizontal Pipe Section(s). Run the horizontal Pipe Section(s) through the hole in the masonry, and connect it firmly to the Tee, either by reaching through the hole, and holding the Tee while twisting the Pipe Section, or by holding the Tee through the access door while someone twist-locks the Pipe Section to it. Use an Adjustable Pipe Length as needed to obtain a specific location for the appliance.
inside of the appliance. This situation can be extremely dangerous, and corrective action must be taken immediately. Common causes of corrosion are listed below: If in doubt call a professional to inspect the vent. (a) If the vent system is located in an area where spray cans or solvents are used extensively, (laundry areas, or paint shops, for example), the halogenated compounds get into the combustion air. When they are burned, they form compounds that cause corrosion.
OVAL B VENT, TYPE BW INSTALLATION NOTES Simpson Dura-Vent Type B Gas Vent shall be used to vent only approved gas appliances with draft hoods and other Category I gas appliances listed for use with Type B Gas Vents: • Water Heaters • Space Heaters • Warm Air Furnaces • Duct Furnaces • Room Heaters • Unit Heaters • Hot Water Boilers • Steam Boilers • Floor Furnaces • Gas Fireplaces • Attic Furnaces Type B gas vents shall not be used for venting incinerators, conversion burners, combination gas/oil appliances
HIGH WIND CAP TABLE 1 DURACAP Roof Pitch STORM COLLAR FLASHING SEE TABLE 1 1 INCH MINIMUM CLEARANCE FIRESTOP SPACER PIPE ENCLOSURE WALL 1 INCH MINIMUM CLEARANCE GAS VENT SUPPORT ROUND PIPE 20 Minimum Height* FLAT TO 7/12 1.0 OVER 7/12 TO 8/12 1.5 OVER 8/12 TO 9/12 2.0 OVER 9/12 TO 10/12 2.5 OVER 10/12 TO 11/12 3.25 OVER 11/12 TO 12/12 4.0 OVER 12/12 TO 14/12 5.0 OVER 14/12 TO 16/12 6.0 OVER 16/12 TO 18/12 7.0 OVER 18/12 TO 20/12 7.5 OVER 20/12 TO 21/12 8.
A gas vent support or firestop spacer must be provided where the vent passes through the ceiling. The ceiling opening is framed, using the same sized lumber as the existing joists, to fit around the raised edge of the gas vent support, which is pushed up into the ceiling from below. The hanger straps are nailed to the framing using 1 1/2-inch box nails to hold the gas vent support firmly, and the clamp is then tightened around the vent pipe.
4-INCH OVAL GAS VENT FOR INSTALLATION IN 2” x 4” STUD WALLS MH6375 CATEGORY I APPLIANCES ONLY 1 INCH MINIMUM CLEARANCE TO COMBUSTIBLES Gas vent shall extend at least 2 feet above the highest point where it passes through the roof, and at least 2 feet higher than any portion of the building within 8 feet. Install oval flashing, storm collar, and oval vent cap. Where pipe passes through the roof, maintain 1-inch minimum clearance to all combustibles. Attach base plate to wall furnace.
DURA-VENT CAP DURA-VENT CAP STORM COLLAR STORM COLLAR ROOF FLASHING ROOF FLASHING OVAL-TO-ROUND ADAPTER NOTE: OFFSET MUST BE SUPPORTED CEILING PLATE BW VENT PIPE OVAL-TO-ROUND ADAPTER CEILING PLATE BW VENT PIPE OVAL TEE BASE PLATE TEE SUPPORT 2” X 4” STUDS 16” OC 2” X 4” STUDS 16” OC 2” X 4” SUPPORT Type BW 2” x 4” Oval Installation 1 2 Type BW 2” x 4” Installation 3 To assemble, align the two pieces, and push them together until they click.
5-INCH OVAL GAS VENT FOR INSTALLATION IN 2” x 4” STUD WALLS MH6375 CATEGORY I APPLIANCES ONLY Where pipe passes through the roof, maintain 1-inch minimum clearance to all combustible materials. Install oval flashing, storm collar, and oval vent cap. Gas vent shall extend at least 2 feet above the highest point where it passes through the roof, and at least 2-feet higher than any portion of the building within 8 feet. Attach base plate to 2” x 4” support.
HIGH WIND CAP DURA-VENT CAP MALE END STORM COLLAR ROOF FLASHING SEE TABLE 1 FEMALE END SUPPORT 1 INCH MINIMUM CLEARANCE TO COMBUSTIBLES OVAL-TO-ROUND ADAPTER To assemble, align the two pieces, and push together until they click. FIRESTOP SPACER Use only vents labeled “For Exterior Use Only”, above roofline. (Canada Only) OVAL PIPE OVAL TEE BASE PLATE AND TEE SUPPORT 2” X 4” SUPPORT Diagram showing transition from 5” oval to round vent pipe, and optional offset.
6-INCH OVAL GAS VENT FOR INSTALLATION IN 2” x 6” STUD WALLS MH6375 CATEGORY I APPLIANCES ONLY Ensure at least 1 inch clearance to all combustibles, including the area the pipe passes through the roof. Install oval flashing, storm collar, and oval vent cap. Gas vent shall extend at least 2 feet above the roof, and at least 2 feet higher than any portion of the building within 2 feet. Attach base plate to 2” x 6” support. Firestop spacers shall be installed as shown on all floors. 1.
HIGH WIND CAP DURA-VENT CAP MALE END STORM COLLAR ROOF FLASHING SEE TABLE 1 FEMALE END SUPPORT 1 INCH MINIMUM CLEARANCE TO COMBUSTIBLES OVAL-TO-ROUND ADAPTER To assemble, align the two pieces, and push together until they click. FIRESTOP SPACER Use only vents labeled “For Exterior Use Only”, above roofline. (Canada Only) OVAL PIPE OVAL TEE BASE PLATE AND TEE SUPPORT 2” X 6” SUPPORT Diagram showing transition from 6” oval to round vent pipe, and optional offset.
SIMPSON DURA-VENT WARRANTY Simpson Dura-Vent Company, Inc. (“Simpson”) provides this limited lifetime warranty for all of its products to the original purchaser, with the exception of Ventinox (lifetime), DuraBlack (five years) and all Termination Caps (five years). Subject to the limitations set forth below, Simpson warrants that its products will be free from substantial defects in material or manufacturing, if properly installed, maintained and used.