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MECHANICAL BACK FASTENED SYSTEM
INSTALLATION DATA AND DETAILS

DESIGN CONCEPT

7/16” Petrarch panels may be installed using flat and/or angle brackets mounted to the back of the panel. This bracket assembly may be anchored to a variety of back-up framing systems, including steel studs/furring (18 ga. min.), or wood framing/furring. For normal wind loads vertical studding should be provided at maximum 24” centers. Horizontal studding is only necessary as back up to the caulking or gasket. For high wind load conditions (over 40 lbs. per sq. ft.) studding may be required at closer centers than 24”. Further details may be obtained from CEP Panels, Inc.

JOINT TREATMENT

Illustrated below is a typical detail using a caulking compound. A good grade sealant should be used in all cases when filling the joints between the panels. Recommendations can be obtained from CEP Panels, Inc.

Joint and panel edges should be free from dust and if recommended by the sealant manufacturer the edges should be primed first. Special care should be taken to avoid the primer from being applied on the face of the panel.

ATTACHMENT HARDWARE

Steel or 1/8" aluminum flat clip

Steel or 1/8" aluminum angle clip

Note: Screws used to attach the bracket to the framing must be stainless steel.

It is mandatory to provide a release at the back of each joint so that the caulking compound will only stick to either edge of the panel and allow for differential movement. To accomplish this, a release, polyethylene or similar bond breaker tape is used. The size of joints will depend on the type of caulking used, but generally caulking width should be twice the depth. The gap between panels should never be less than 3/8”-- 1/2” is strongly recommended. It may be necessary to increase the gap for full width panels used in areas of extreme temperature variation

BRACKET FASTENING

Each bracket is attached to the back of the panel by means of one or two threaded, expanding, brass board anchors inserted into blind holes drilled in the back of the panel. These are designed to accept bolts used to attach steel or 1/8” aluminum flat or angle clips. It is vitally important that the drilling for and insertion of the board anchors is carried out under controlled conditions to insure the correct diameter and depth of the hole. This operation should therefore not be carried out on the job site, but in a properly equipped fabrication shop; such as provided at the CEP Panels manufacturing facility or an approved alternative.

Once the brackets have been attached to the back of the panel the assembly is fastened to the back-up framing by means of the appropriate screws at the joint through the flat bracket extensions. These are subsequently covered by the sealant thus providing a completely hidden fastening system without the need for access to the back of the panel. Bracket fastening centers should not exceed 24”. Fastening points at intermediate stud locations can utilize angle brackets as shown; providing the panels are accessible from the back. When rear accessibility is not possible, alternate clip designs and the incorporation of structural silicone stiffener beads can be approved options. Contact CEP Panels, Inc. for further information.

BRACKET POSITIONING

The number of bracket locations required will depend on the panel size and the dead and wind loading. Typically, brackets are required at 24” centers providing adequate holding to carry the dead weight of the panel and wind loading (suction) up to 40 lbs. per sq. ft. In many cases, panels 3’0” wide or less require edge brackets only. Panels over 3’0” require intermediate angle brackets as well as edge brackets. In all cases where edge brackets are used they are staggered when two panels meet forming a joint.

ALTERNATIVES TO BRACKETS

All details offered by CEP Panels, Inc. are suggestions and have been used successfully on many projects. Locally sourced accessories, such as brackets and washers, in other sizes and materials, can be used. Details using one piece stiffeners, interlocking hanging brackets and other designs have been used and may be reviewed on a job to job basis by CEP Panels, Inc. These should ultimately be presented to and approved by the architectural or site engineer.