Abstract: A method of manufacturing a thermally insulated building block (54a) comprises foaming a quantity of foamable plastics material in an enclosed space (56) between a building block (54) and a closure means (52), the quantity of material being sufficient to fill the enclosed space (56). The foamable material may be injected into a cavity in the block onto an outer surface of the block (54) or onto the closure means (52) prior to locating the block (54) and closure means (52) relative to each other to form the enclosed space (56) therebetween. The block (54) is transported between upper and lower parallel endless belts (55, 50) during foaming and either belt (55, 50) may provide the closure means (52). If the lower belt (50) provides the closure means (52) the upper belt (55) maintains the block (54) in contact with the closure means (52) during foaming.

Abstract: This invention relates to methods and apparatus for successively dispensing predetermined quantities of urea formaldehyde foamed resin mixture having as constituents a resin component and a hardener component in which a prefoamed one of said components and the other component are independently fed under pressure to a mixing chamber where they are mixed and from which, they are dispensed, any residue of the urea formaldehyde foamed resin mixture left in the mixing chamber after said predetermined quantity has been dispensed therefrom being swept and removed prior to the mixing chamber being supplied with the next batch of said components.The present invention is particularly useful for filling pre-cast cavity building blocks with insulating foamed material.