The IS 2547 Part 2 (1976) standard outlines the specifications for premixed lightweight gypsum plasters used in building construction. It details the composition, physical and chemical characteristics, classification, sampling protocols, testing methods, and labeling criteria for gypsum plasters containing lightweight aggregates such as expanded perlite and vermiculite. This code is critical for professionals involved in manufacturing, quality assurance, and the practical use of lightweight gypsum plasters for both base and finishing layers.
Overview
The IS 2547 Part 2 (1976) standard outlines the specifications for premixed lightweight gypsum plasters used in building construction. It details the composition, physical and chemical characteristics, classification, sampling protocols, testing methods, and labeling criteria for gypsum plasters containing lightweight aggregates such as expanded perlite and vermiculite. This code is critical for professionals involved in manufacturing, quality assurance, and the practical use of lightweight gypsum plasters for both base and finishing layers.
Audience
Contents
Structure
This section defines the scope of premixed lightweight gypsum building plasters, focusing on their chemical and physical property requirements. It includes formulas for calculating soluble sodium oxide (Na2O) percentage and explains free lime content determination. Quality control procedures involve statistical evaluation of test results within specified tolerance limits. Reference standards such as IS 4032-1968 and licensing provisions by the Bureau of Indian Standards are also highlighted.
Defines essential terms specific to gypsum building plaster to ensure consistent understanding. Describes statistical methods for evaluating test outcomes, including calculation of average and range, with acceptance criteria based on these values. Explains chemical analysis calculations for sodium oxide and free lime content with relevant formulae and test procedures.
Details the categorization of lightweight gypsum plasters into types based on their intended use: undercoat plasters (including browning, metal lathing, and bonding plasters) and final coat plaster (finish plaster). Provides key physical and chemical specifications for each category, including density limits, compressive strength, free lime content, and mechanical resistance parameters.
Specifies the necessary physical and chemical characteristics that premixed lightweight gypsum plasters must satisfy. Details testing methods for soluble sodium oxide, free lime, and soluble magnesium oxide, including sample preparation and chemical analysis procedures. Emphasizes adherence to IS codes and composite sampling for quality assurance.
Outlines the procedures for sampling from production lots, including the number of packages to be sampled based on lot size. Describes the testing of individual and composite samples for compliance with specifications. Acceptance criteria for lot conformity are explained, ensuring statistically valid quality control.
Describes the mandatory labeling information on plaster packages, such as manufacturer details, plaster type, production date, and net weight. Discusses sampling protocols for testing and requirements for sample storage to maintain integrity. Highlights optional use of the Standard Mark under BIS regulations for product certification.
Explains the analytical methods for measuring soluble magnesium oxide and sodium oxide content in gypsum plaster samples. Includes detailed calculation formulas, sample preparation steps, and references to IS standards applicable to these chemical analyses.
Provides the formulae and procedures for assessing free lime content in gypsum plaster, including titration techniques and statistical evaluation of results. Specifies sample sizes and acceptance criteria, accompanied by sampling tables and flowcharts to guide testing processes.
Frequently Asked
IS 2547 Part 2 classifies premixed lightweight gypsum plasters into two primary categories. Type A includes undercoat plasters such as browning plaster, metal lathing plaster, and bonding plaster, which serve as base layers for subsequent coatings. Type B comprises final coat plaster, specifically finish plaster, which provides the smooth top surface. These plasters combine retarded hemihydrate gypsum with suitable lightweight aggregates and additives to fulfill their respective functions.
The standard permits the incorporation of suitable lightweight aggregates compliant with IS 2547 Part 1: 1976. Specifically, expanded perlite and exfoliated vermiculite are allowed as lightweight fillers within the premixed gypsum plaster. These aggregates contribute to reduced density and improved thermal properties without compromising the plaster’s performance.
IS 2547 Part 2 specifies minimum compressive strengths for different plaster categories in Table 1, Clause 4.1. Browning plaster requires at least 0.93 N/mm², while metal lathing and bonding plasters each require a minimum of 1.0 N/mm². The final coat plaster’s compressive strength is not explicitly stated in this part but is expected to provide adequate finishing properties as detailed in related standards.
Samples should be randomly selected from each production lot in accordance with procedures akin to IS 4905-1968, ensuring unbiased selection. The number of packages sampled depends on the lot size, ranging from three packages for lots up to 100 to ten for lots exceeding 500 packages. Tests for compressive strength and free lime content must be performed on individual samples stored in clean, dry, airtight containers, while other tests are conducted on composite samples. Compliance is confirmed when all test results meet the specified criteria.
Each plaster package must be clearly marked with the manufacturer’s name, the type of plaster (undercoat or final coat), the date of manufacture, and the net weight of the contents. This labeling ensures correct identification and appropriate use. Additionally, the optional use of the Standard Mark may be included if the product is certified under BIS licensing provisions.
Ask AI about any clause, requirement, or provision in IS 2547 PART 2. Get instant, clause-cited responses powered by our indexed library.
Free tier includes 150 queries (50 AI + 100 Reference) · No credit card required