Roofing Glossary - NB Handy

Tin Plate Base Box - A tin plate box is measured in terms of pounds per base box (112 sheets 14" x 20"), a unit peculiar to the tin plate industry. This corresponds to an area of sheet totaling 31,360 square inches of any gauge and is applied to tin plate weighing from 55 to 275 pounds per base box. ................
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