摘要 |
Disclosed is a duct board assembly which comprised a panel of conventional duct board formed of rigid thermal insulation to which is attached boardering strips on one face of the panel; the panel may be provided with spaced, longitudinal grooves to define the wall widths of an air duct section to be formed from the duct board assembly and the outer margins of said panel-framing strips being provided with locking means to provide a closed longitudinal seam for the air duct section and to provide for closed joining, end-to-end, of successive duct sections.
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