STRUCTURAL FIBER CEMENT BUILDING MATERIALS COMPRISING LOW DENSITY ADDITIVES AND HAVING A GROOVE CONTAING A MEMBRANE PROTECTED ADHESIVE THEREIN

摘要

Disclosed is a fiber cement sheet comprising: a cementitious matrix comprising a hydraulic binder (typically Portland cement) in an amount in the range of from about 25 to about 40 weight percent, and an aggregate (typically aggregate silica) distributed throughout the matrix, wherein the aggregate is present in an amount in the range of from about 30 to about 45% by weight, and reinforcing cellulose fibers distributed throughout the matrix, wherein the reinforcing cellulose fibres are present in an amount in the range of from about 10 to about 12% by weight, at least one low density additive distributed (such as microspheres) throughout the matrix, wherein the at least one low density additive is present in an amount in the range of from about 7 to about 12% by weight, wherein the sheet further comprises: a top face, a bottom face, and two sets of opposing parallel edges, wherein at least one edge contains a groove formed therein, the groove having a membrane situated therein encapsulating an adhesive, wherein the membrane is configured to resist puncture during transport and prior to installation and configured to permit puncture upon sufficient contact with an edge of an adjacent building sheet during installation.