Division 9 C E I L I N G S Y S T E M S & S P E C I A LT Y P R O D U C T S TD-C-17 Technical Data Thermal Expansion Joints in Suspended Ceilings Exposed Systems Large continuous areas of suspended ceilings sometimes require expansion joints. Here is an easy method for making them by using CMC wall angles. Fig. 1 shows the expansion joint in profile. It is composed of three 1434 wall angles, two of which, A and B, are pop riveted together into one unit which C helps support. The A-B unit and C fit into a 1앨 space left between runners or tees as shown in Fig. 2 and are pop riveted to the components as described in the following sections. Wall angle A provides a dust cover on top and B and C firmly space the components, preventing the ceiling material from shifting. The expansion joint will allow 1앨 of movement in either direction and should be installed at 72° F and maximum intervals of 48쎾 on center for 2쎾, 4쎾 or 6쎾 modules, or 50쎾 for 5쎾 modules. With minor alterations, the basic method can be used with all CMC ceiling systems – exposed, modular, concealed and drywall furring. Fig. 1 A Pop Rivet Suspension Components 1앨 1앨 1앨 B C 2 1/2앨 Fig. 2 Method 1 A B C Flange Fig. 3 Pop Rivet Method 2 An optional way of creating expansion joints utilizes the 839 coupling cover (Fig. 4). This method allows expansion joints to be created without interruption of the ceiling plane. Multiple spaces/expansion joints are created along the main runner span to fulfill the requirements of the installation. The end tabs of the main runners are snipped off to prevent coupling. To avoid buckling or compression of ceiling tiles the gap between main runners should not exceed 1/4앨 for each joint. Step 1: Components that cross the path of the expansion joint are straight cut (Fig. 2), and those that end on the path have their couplings or tabs, if any, snipped off. Step 2: Punch hanger holes as needed (Fig. 2) keeping those on one side at least 21/2앨 from the component ends to allow for movement. Suspend the components 1앨 apart. Step 3: If a painted recess is required (Fig. 1), paint the galvanized side of A. Step 4: Punch and pop rivet A and B together into one unit at points that will not interfere with the on center spacing of the components. Step 5: Temporarily space the components with the proper length spacer bars, cross tees, variable cross tees or other method. Step 6: Insert the A-B unit (Fig. 3) into the 1앨 space and pop rivet the short leg of B to the component flanges on one side; do the same with C on the other side. Step 7: Remove the spacer bars, etc., and install the acoustical lay-in panels. Fig. 4 Technical Data Concealed Systems Fig. 5 Direct Hung, Z and T & G Step 1: If the components end on the path of the expansion joint and have couplings or tabs at least 1/2앨 long, bend these connectors inward 90°. If the components have shorter couplings or tabs, or none at all, make 1/2앨 connectors by snipping back the component flanges and bulbs or legs; bend the webs or center sections inward 90°. Components that cross the path of the expansion joint are straight cut and connectors are made as described above. Repeat Steps 2 through 5 from the Exposed Systems directions. Step 6: Insert the A-B unit (Fig. 5) into the 1앨 space and pop rivet the long leg of B to the bent connectors, allowing B’s short leg to hang one half the tile thickness below the component flanges. Do the same with C, pop riveting from the back side of the expansion joint, as shown. Step 7: Remove the spacer bars, etc. and install the concealed acoustical tile and splines as usual. A Pop Rivets Acoustical Tile B C Suspended Drywall Furring Systems A B Repeat Steps 1 through 6 from the Exposed Systems directions. Step 7: Remove the spacer bars, etc. Install “J” moldings to the exposed edges of the drywall panels at the expansion joint (Fig. 6). Secure the panels to the component flanges with self-tapping screws, keeping the panels 1앨 apart to allow for movement. C Gypsum Panel “J” Molding Fig. 6 Fig. 7 Nail A 2 1/2앨 1앨 Wall Treatment Step 1: If an expansion joint is required along a wall (Fig. 7) attach A to it with appropriate screws or nails. Step 2: Prepare the component ends as shown in Step 1 of the preceding appropriate ceiling system directions. Step 3: Punch hanger holes as needed, keeping them at least 21/2앨 from the component ends. Suspend the components 1앨 from the wall (Fig. 7) and so that C will contact A when attached to the components as shown. Step 4: Repeat Step 5 from the Exposed Systems directions. Step 5: Pop rivet C to the components according to Step 6 of the preceding appropriate ceiling system directions. Step 6: Remove the spacer bars, etc. and (Fig. 6) install the appropriate ceiling material (exposed shown). C C E I L I N G S Y S T E M S & S P E C I A LT Y P R O D U C T S U.S. Toll Free: 800-323-7164 앫 Fax: 800-222-3744 앫 WWW.chicago-metallic.com CHICAGO 앫 BALTIMORE 앫 LOS ANGELES ANTWERP 앫 HONG KONG 앫 SINGAPORE 앫 PARIS 앫 LONDON 앫 MILAN 앫 FRANKFURT 앫 SEOUL © 1998 Chicago Metallic Corporation All Rights Reserved Chicago Metallic and its logo are Registered Trademarks of Chicago Metallic Corporation. TD-C-17-1299CC Printed in USA Literature Disclaimer: Presentations in this brochure or any other Chicago Metallic Corporation publication are correct to the best of our knowledge at time of preparation. We provide this information in an advisory capacity only. Any advisory recommendations given in our publications must be modified to conform with local codes, conditions and specifications. We reserve all rights to amend any information published in our literature without additional notice. 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