H—44A

Building-boards. —A standard specification lias been completed for three types of interior wallboard in common use —milled paper board, fibre board, and plaster-cored paper-covered wallboard. In addition to uniform dimensions, the specification establishes general and detailed requirements in respect of each type of wallboard, including minimum weights to the square yard, and minimum transverse strengths, these being the factors which primarily determine the quality of the board. Further investigational work is now being carried out with a view to supplementing the specification with provisions that will establish requirements relating to fire resistance, thermal conductivity, water permeability, thermal expansion and acoustical properties. Asbestos-cement Roofing-sheets.—The standard code of practice for the fixing of asbestos-cement roofing-sheets, referred to in the last report, has now been completed and issued. This code supplements the standard specification for roofing-sheets by establishing minimum requirements for, and defining the practice to be followed in the fixing of such sheets. Adherence to both the standard specification and the code of practice will ensure that roofing-sheets will be of such a quality, and so fixed, that they will yield satisfactory service, and in particular will eliminate the undue hazards to workmen, firemen, and others called upon to work on roofs of asbestos-cement sheets. Roofing-tiles. —The standard specification for earthenware roofing-tiles referred to in the last report was issued during the year. It specifies two size-patterns, one for the North Island and one for the South Island, and will thereby eliminate the confusion and waste which results from the indiscriminate use of tiles of different sizes and patterns. The specification will also enable manufacturers to reduce unit-production costs by confining their production to a minimum number of tile types. Users, on the other hand, will be assisted by the knowledge that tile replacements will be readily obtainable. The specification also lays down minimum requirements in respect of the factors which determine the quality of the tiles, including dimensions, transverse strength, absorption, workmanship and finish, and includes the necessary provisions in respect of testing and marking. A similar standard specification for concrete roofing-tiles, and a standard . code of practice for the fixing of both concrete and earthenware tiles, have been completed during the year, and will be issued as soon as they have been finally edited. Wire Nails and Staples. —A special committee set up to formulate standard specifications for wire nails and staples has taken as the basis for the specification for wire nails a draft British Standard which has been circulated to the interested parties in New Zealand for examination and comment. A special sub-committee is to review the draft specification in the light of the comments received, and will amend its provisions where necessary to bring them into line with New Zealand's requirements. A preliminary draft specification for staples has been prepared. Fibrous Plaster Sheets. —A standard specification for fibrous plaster sheets for indoor use has been completed except for provisions relating to transverse strength, in respect of which tests are being conducted to determine the requirements which should be incorporated. The specification provides for two grades of sheet, one suitable for painting and the other suitable for papering. In addition to laying down strength requirements, the specification will establish standard dimensions and minimum requirements concerning composition and moisture content. A standard specification has been completed for gypsum casting plaster, and preliminary work has begun on the preparation of a specification for fibre for use in fibrous plaster products. Second-hand Corrugated Roofing-iron. —At the request of the Price Tribunal, a standard specification has been issued establishing grades for second-hand corrugated roofing-iron. Paints and Coatings Seetional Committee (Four meetings) Paints and Coatings Panel .. .. .. .. .. One meeting. Parent Committee. —During the year the '>. Lt committee examined 2 draft British standards, 1 British emergency standar . A i vrican standards, and 6 Canadian standards. The British emergency - mdar 'as f >und to be unsuitable for adoption in New Zealand. One of the draft British f - , and 3of the Canadian standards

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