Evaluation of normal-weight and light-weight fillers in extruded cellulose fiber cement products

Extruded fiber cement products offer advantages in terms of the versatility of section profiles, end product performance characteristics, and production throughput. Wood fibers offer a desirable balance of performance and cost as reinforcement in extruded wood fiber cement products. The research reported herein assessed the effects of normal-weight (silica sand) and light-weight (expanded shale) fillers on mechanical, physical and durability characteristics of extruded cement products reinforced with softwood, hardwood, and recycled fibers. Fillers caused improvements in moisture resistance and durability of extruded wood fiber cement products. Their presence, however, lowered the flexural strength and nailability of fiber cement boards.