Used in openings that contain multiple type and/or size of fenestration product, which when joined must form a structural system that can withstand a required design pressure.
To provide an easily read, reliable source of information for the engineer, architects, builder, etc. Lawson provides third party certification of its mullion’s when used with a variety of product, keyed to mull type, length, fastener type, and design pressure.
Refer to Lawson mullion N.O.A. for details on our aluminum mullions that come with or without steel reinforcing, can be used in spans up to 150″ and can be used in all impact or non-impact installations.
1” x 3”, 1” x 4”, 2” x 4”, 2” x 6” rectangular tubes
Multiple Section Sizes. Multiple mullion depths from 3″ to 6″ deep, available with or without steel reinforcing, allow the mullion to be truly sized for each unique opening.
Flange Frame Mullions Available. Aluminum mull sizes range from 1” x 2”, 1” x 3”, 1” x 4”, 2” x 4” and 2” x 6” tubes. (A non tubular 4” mull is available for non wind load exposed openings, but N.O.A. data is not available, nor can it be provided.)
Fin Frame Mullions Available. Aluminum mull size is 1” x 2” and 1” x 3” tubes. (A non-tubular 4” mull is available for non wind load exposed openings however, no N.O.A. data is available, nor can it be provided.)
Custom sizes Mullions are cut in length as required to fit any opening.
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