Abstract: As disclosed herein, the dry density of a board product is monitored, preferably continuously so. The board is made by a wet forming process, which process includes preparing an aqueous slurry of at least some of the board's components, depositing the slurry upon a moving screen to form a moisture-laden sheet thereon, and removing the moisture to form the ultimate product. The dry density of this product is monitored by first simultaneously and automatically measuring the wet weight, moisture content and thickness of the water-laden sheet on the moving screen and from these measurements automatically calculating the dry density of the board product to be produced from the measured sheet.