IS 12118:1987 Part 1 is the Indian Standard (BIS) for polysulphide based sealants - code of practice for use in building construction. This code of practice (Part 1) provides guidelines for the use of two-component polysulphide based sealants for sealing joints in building construction. It covers essential aspects like joint design, surface preparation, sealant application, and curing to ensure a durable, weatherproof seal.
Provides recommendations for the selection, application, and maintenance of polysulphide based sealants in building construction.
| Parameter | IS Value | International | Source |
|---|---|---|---|
| Minimum Recommended Joint Width | 6 mm | 6 mm (1/4 in) | ASTM C1193 |
| Width to Depth Ratio (for joints > 12mm) | 2:1 | Generally 2:1 is recommended, with depth not exceeding 13mm (1/2 in) | ASTM C1193 |
| Width to Depth Ratio (for joints ≤ 12mm) | 1:1 | 2:1 is still preferred, but depth should not be less than 6mm (1/4 in) | ASTM C1193 |
| Recommended Application Temperature Range | 5°C to 40°C | Generally above 4°C (40°F), but strongly advises following sealant manufacturer's specific data sheet. | ASTM C1193 |
| Requirement for Primer | Generally required for porous surfaces; may be required for non-porous surfaces. | Determined by manufacturer's recommendation and/or job-site adhesion testing. | ASTM C1193 |
| Maximum Recommended Joint Width | 25 mm (up to 40 mm with special precautions) | Typically 25-50 mm (1-2 in), but requires consultation with manufacturer for widths over 25 mm. | ASTM C1193 |
| Backer Rod Compression | 20 to 25 percent | Typically 25 to 50 percent, depending on the backer rod type (open-cell vs closed-cell). | General industry practice referenced in guides like ASTM C1193 |