Composite roofing structures can include mineral fiber roof cover boards with high concentration of mineral wool or mineral wool and perlite. The roofing structure may include: a roof cover board including a dried base mat including: 8-25% mineral wool, 40-65% perlite, 9-15% binder, 9-15% cellulosic fiber, and 0.25-2% sizing agent, all % by weight; an insulation layer; and a roofing membrane. The roof cover board is over the insulation layer, the roofing membrane is over the roof cover board. The roof cover board is attached to the insulation layer. The roofing membrane is attached to the roof cover board. Alternatively dried base mat may include: 30-70% mineral wool, 10-50% perlite, 5-15% binder, 2-20% cellulosic fiber, and 0.25-2% sizing agent. Alternatively the dried base mat may include: 60-90% mineral wool, 0-10% fiber, 0-10% perlite, 4-10% binder, 0-5% gypsum, and 0.25-2% sizing agent.

The disclosure provides a method of decreasing the water load needed to form a fibrous panel. The process includes admixing a mineral wool, a cellulose, and a binder to provide a pre-mixed slurry, admixing a mineral filler with water to provide a mineral filler slurry, admixing the pre-mixed slurry and the mineral filler slurry to form a dispersion, flowing the dispersion onto a foraminous support wire to provide a green board, dewatering the green board to form a dewatered green board and drying the dewatered green board to provide a fibrous panel.

The disclosure provides a method of decreasing the water load needed to form a fibrous panel. The process includes admixing a mineral wool, a cellulose, and a binder to provide a pre-mixed slurry, admixing a mineral filler with water to provide a mineral filler slurry, admixing the pre-mixed slurry and the mineral filler slurry to form a dispersion, flowing the dispersion onto a foraminous support wire to provide a green board, dewatering the green board to form a dewatered green board and drying the dewatered green board to provide a fibrous panel.

Acoustical tile including a dried base mat of: about 70 to about 90 wt % mineral wool; about 5 to about 15 wt % perlite; 0 to about 10 wt % starch; about 3 to about 10 wt % latex; 0 to about 5 wt % gypsum; and less than 5 wt % water. The dried base mat without including glass fibers and without a laminate layer or coating and without perforations has a NRC of about 0.70 or greater, a density of about 10 pcf to about 12 pcf, and a thickness of about to about 1 inch. The acoustical tile can further include a back coating at a surface weight of about 5 grams per square foot (gsf) to about 40 gsf to the dried base mat, wherein the acoustical tile has the CAC rating of about 30 to about 35.

Acoustical tile including a dried base mat of: about 70 to about 90 wt % mineral wool; about 5 to about 15 wt % perlite; 0 to about 10 wt % starch; about 3 to about 10 wt % latex; 0 to about 5 wt % gypsum; and less than 5 wt % water. The dried base mat without including glass fibers and without a laminate layer or coating and without perforations has a NRC of about 0.70 or greater, a density of about 10 pcf to about 12 pcf, and a thickness of about to about 1 inch. The acoustical tile can further include a back coating at a surface weight of about 5 grams per square foot (gsf) to about 40 gsf to the dried base mat, wherein the acoustical tile has the CAC rating of about 30 to about 35.

The present invention relates to a process for producing precast products in an airtight enclosure, which comprises the steps of a carbonation of pre-dried concrete precast units by feeding CO.sub.2 gas into a closed airtight enclosure under near ambient atmospheric pressure (psig between 0 and 2) and/or low pressure (between 2 and 15 psig) conditions, wherein said pre-dried concrete units have lost between 25 to 60% of their initial mix water content.

The object of the invention is a construction material containing water glass, fumed silica, ground sand and post-industrial waste material, characterised in that the post-industrial waste material constitutes dried flotation tailings with a content of 19.67-57.24% of SiO.sub.2; 11.87-24.85% of CaO; 4.23-6.19% of MgO and 2.35-4.17% of Al.sub.2O.sub.3, and also the object of the invention is a method for preparing the construction material.

A dry papercrete mix is formed by preparing a wet pulp of fiber material such as newsprint and sharp sand by mixing sand, fiber material and water in a batch or continuous mixer, drying the pulp to a moisture content below that which will cause a reaction with Portland cement and adding additional sands and/or pumice and Portland cement. The resulting dry, granular mix can then be handled stored and used in the manner which is conventional for concrete. The dry papercrete mix can also be applied by pouring the dry papercrete mix into a desired volume such as a form in a dry state and injecting water into the dry papercrete mix until the mix is sufficiently wetted without a requirement for mixing in the manner common for concrete. Structural modules and a technique for joining them into a structure are particularly appropriate to the use of dry application papercrete.

A dry papercrete mix is formed by preparing a wet pulp of fiber material such as newsprint and sharp sand by mixing sand, fiber material and water in a batch or continuous mixer, drying the pulp to a moisture content below that which will cause a reaction with Portland cement and adding additional sands and/or pumice and Portland cement. The resulting dry, granular mix can then be handled stored and used in the manner which is conventional for concrete. The dry papercrete mix can also be applied by pouring the dry papercrete mix into a desired volume such as a form in a dry state and injecting water into the dry papercrete mix until the mix is sufficiently wetted without a requirement for mixing in the manner common for concrete. Structural modules and a technique for joining them into a structure are particularly appropriate to the use of dry application papercrete.

The present invention relates to a low water content plastic composition comprising hydraulic cement and a method for manufacturing the same. The present invention provides a low water content plastic composition comprising hydraulic cement and a method for manufacturing the same, the composition being characterized by losing flowability and having plasticity since from a flowable, uniform mixture state of hydraulic cement and water with polyol and isocyanate compounds which are raw materials for forming foamed polyurethane, part of the water used in the mixture is separated and removed due to foaming in the course of formation of the foamed polyurethane.