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Roof covering materials for pitched roof
Short answer
Pitched roof coverings: thatch (cheap, insulating, fire risk, 45-60° slope), clay tiles (durable, heavy, 25-45° slope), slates (durable, fireproof, costly), stone slabs (heavy, hilly areas), AC sheets (light, fire resistant, asbestos hazard), GI/CGI sheets (light, quick fixing, noisy, common in Nepal), aluminium/coloured steel (rust-resistant, costly), plastic/polycarbonate (translucent, low strength), wooden shingles (insulating, fire risk).
Explain different types of roof covering materials for pitched roof.
Roof covering is the outer weather-proof layer laid over the rafters/battens of a pitched roof. The choice depends on climate, slope, cost and availability.
| Covering | Main properties and use |
|---|---|
| Thatch (straw, khar, reed) | Cheapest, good insulation, high fire risk, needs 45-60 degree slope, short life |
| Clay tiles (country, Mangalore, Allahabad) | Good insulation, durable, heavy, need close battens; slope 25-45 degrees |
| Slates | Durable, fire resistant, neat; heavy and costly; slope above 25 degrees |
| Stone slabs (patthar) | Used in hilly Nepal; very heavy, durable, needs strong rafters |
| AC (asbestos cement) sheets | Cheap, light, fire resistant; brittle, health hazard (asbestos) |
| GI / CGI sheets | Light, easy and quick fixing, durable if coated; noisy, hot, can corrode |
| Aluminium / coloured steel sheets | Light, rust-resistant, many colours; costly |
| Plastic / fibre / polycarbonate sheets | Light, translucent; low strength, UV ageing |
| Wooden shingles | Good insulation, attractive; fire risk, decay |
Brief notes
- Thatch: bundles of straw or reeds tied on bamboo/timber battens at 45-60 degree slope; cheap and cool but burns easily.
- Tiles: clay tiles (Mangalore, country tile) hung on battens; good thermal comfort and durable.
- Slate: thin sheets fixed with nails; very durable, fire proof, expensive.
- AC and CGI sheets: large light sheets fixed by hook bolts to purlins; quick and economical, CGI most common in Nepal.
- Stone slate (patthar): used in hilly regions of Nepal, very heavy.
✓ Answer checked by Claude Opus 5.5 (high effort)
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