concrete block

The wall consists of 100-mm common bricks, a 90-mm air space, 100-mm concrete blocks made of lightweight aggregate, a 20-mm air space, and a 13-mm gypsum wallboard. The wall board is separated from the concrete block by 20-mm-thick (1-in. 3-in. nominal) vertical furring whose center-to-center distance is 400 mm.

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