IS 6313 (Part 1) : 2000Code of practice for anti-termite measures in buildings, Part 1: Constructional measures

IS 6313 (Part 1):2000 is the Indian Standard Code of Practice for Anti-Termite Measures in Buildings — Part 1: Pre-Constructional Chemical Treatment. It is the mandatory pre-construction termite-prevention protocol for new buildings in termite-prone India.

Use it when: - Designing or specifying any new building — virtually all of India (except dry Himalayan / arid Rajasthan regions) is termite-active. NBC 2016 Part 6 makes pre-construction treatment effectively mandatory. - Auditing contractor anti-termite work — the most-cheated trade. Chemical can be diluted, locations skipped, or treatment falsified. Verification is critical. - Investigating termite damage in a relatively new building — first check whether documented IS 6313 Part 1 treatment was actually applied and certified - Specifying for high-risk locations — coastal Maharashtra, Karnataka, Tamil Nadu, Andhra, Kerala, and parts of north-east India have heaviest termite pressure; specify higher chemical concentration and additional treatments per IS 6313 Part 2 (post-construction)

Companion codes: - IS 6313 Part 2:2013 — Post-construction chemical treatment (for existing buildings) - IS 6313 Part 3:2001 — Treatment for existing buildings - IS 8944:2005 — Code of practice for chlorpyriphos emulsifiable concentrates (the chemical specification)

IS 6313 Part 1 prescribes treatment at five specific construction stages (Clauses 5-9). Each stage targets a different termite access path. Skipping any stage leaves a vulnerability.

Stage 1 — Bottom and sides of foundation excavation (Clause 5.2): - Apply chemical to the bottom of foundation pits and trenches at rate of 5 L/m² of horizontal surface - And to vertical sides of pits up to 300 mm above excavation bottom: 5 L/m² of vertical surface - Applied IMMEDIATELY before concrete is poured (within 1-2 hours; otherwise sun + wind dries the chemical)

Stage 2 — Refill earth alongside foundation (Clause 5.3): - After foundation concrete is cured and backfilling begins, treat the earth surrounding foundation walls - Rate: 7.5 L per linear metre per 300 mm depth of backfill for both sides of foundation walls - Applied as each layer of backfill is placed (typically every 300 mm lift)

Stage 3 — Plinth filling and consolidation (Clause 5.4): - Treat the soil mass that will become the plinth fill (under the ground floor slab) - Rate: 5 L/m² of horizontal surface of the plinth area - Applied AFTER filling and consolidation but BEFORE the damp-proof course (DPC) is laid - Common omission: site engineers think 'we already treated the foundation pits' — but the plinth slab area is a separate exposure that needs its own dose

Stage 4 — Junction of column / wall with floor (Clause 5.5): - Treat the strip around all RCC columns and load-bearing walls at the floor-junction level - Rate: 0.6 L per linear metre of junction - Applied just before flooring is laid - This catches the most common termite entry path — termites climb up the wall-floor junction via fine cracks

Stage 5 — Soil along external perimeter of building (Clause 5.6): - Treat the soil along the external perimeter of the building, both before plinth protection is laid AND in a 300 mm trench dug around the perimeter - Rate: 5 L per square metre of vertical surface of the foundation wall, AND 7.5 L per linear metre of trench - Forms a 'chemical barrier' around the building perimeter

Chemical and concentration (Clause 4): - Chlorpyriphos 20% EC at 1.0% emulsion (industry standard since the late 1990s) — diluted in water 1:19 with water - Older codes specified Aldrin / Heptachlor / Chlordane at 0.5-1.0% — banned globally and in India since the early 2000s due to environmental persistence (POPs — Persistent Organic Pollutants) - Permethrin / Cypermethrin / Imidacloprid / Bifenthrin are newer alternatives — IS 8944 series covers their specifications - For organic / green-building projects: physical barriers (sand grading, steel mesh, plastic geomembrane) per IS 6313 Annex C are permitted in place of chemical treatment

Anti-termite treatment is the most cheated trade on Indian construction sites. The chemical is colourless once mixed; once sprayed, you can't see it; once concrete is poured, you can't recover any evidence. Contractors routinely dilute the chemical, skip stages, or fake the treatment entirely.

Practical verification checklist for PMC / supervisor:

1. Pre-arrival: contractor must deliver chemical in sealed manufacturer containers with batch number, manufacturing date, expiry date. Reject any open / unsealed / re-labelled containers.

2. Concentration check: at site, witness the dilution mixing. The contractor draws X litres of chemical concentrate (20% EC) and adds 19X litres of water to get 1.0% emulsion. Verify the ratios with a measured bucket. If the contractor 'measures by eye', insist on a calibrated container.

3. Per-stage measurement: for each stage, calculate the EXPECTED quantity: - Stage 1 (foundation pits, 5 L/m²): for a 100 m² total foundation footprint, expect 500 L of emulsion = 25 L of concentrate + 475 L of water - Stage 3 (plinth, 5 L/m²): for a 100 m² building footprint, expect another 500 L of emulsion - Etc. - Verify per-stage consumption against site quantities BEFORE next stage proceeds

4. Application witness: don't just check the totals; witness application. Spray rate, coverage, locations all matter. Phone-camera time-stamped photos help, but on-site supervision by junior engineer (or surrogate) is the gold standard.

5. Treatment certificate (Clause 11): contractor must issue a written certificate stating stages applied, dates, quantities, chemical batch numbers, and treated person's signature. Mandatory for fire NOC / structural clearance in some ULBs.

6. Warranty: BIS-licensed pest-control firms (Truly Nolen, Rentokil PCI, ZX-Pest, large local firms) provide 5-year warranty on properly executed IS 6313 Part 1 treatment. For ₹10,000-15,000 premium over an untrained contractor doing the spraying, the warranty is worth it.

1. Diluting chemical further than specified — contractor cheats by using 0.3-0.5% emulsion instead of 1.0%, doubling or tripling the visible quantity sprayed. Result: insufficient barrier; termites cross within 1-2 years. Concentration verification is essential.

2. Skipping stages 2-3-4 — many sites only do Stage 1 (foundation pits) because that's visible. Stages 2 (backfill), 3 (plinth), 4 (junctions) are equally important but harder to verify, so they get skipped.

3. Treatment applied too long before subsequent work — if Stage 1 is applied on Monday but concrete pour is Friday (4 days later), the chemical has degraded from sun and wind exposure. Re-treat or apply Stage 1 the day of pour.

4. Using expired or counterfeit chemical — chlorpyriphos shelf life is 2-3 years in sealed containers. Expired chemical has degraded active ingredient. Verify expiry date on every container.

5. No treatment around utility entries — termites favourite entry path is along electrical conduits, plumbing pipes, and AC drain pipes entering through the foundation/plinth. Stage 4 (junctions) often misses these. Treat 1 m around all utility entries.

6. Wet weather treatment — chemical applied to wet/muddy soil washes away during rain. Schedule treatment for dry weather only. If rain occurs within 48 hours of treatment, re-treat affected areas.

7. Treating only when building is plinth-level — many sites start anti-termite treatment after plinth is already poured. Stages 1 and 2 are now impossible. Late-stage treatment is post-construction (Part 2) protocol, which is less effective.

8. No documentation handed to building owner — when the building changes hands or seeks fire NOC renewal, the absence of an IS 6313 Part 1 certificate raises questions. Hand over a complete file: chemical batch certificates, per-stage application logs, signed contractor certificate.

• IS 6313 Part 2:2013 — Anti-termite measures in buildings — Post-constructional chemical treatment
• IS 6313 Part 3:2001 — Anti-termite measures — Treatment of timber and bamboo
• IS 8944:2005 — Specification for chlorpyriphos emulsifiable concentrates
• IS 5006:1984 — Specification for parathion (older, less used)
• NBC 2016 Part 6 — Materials and Construction (mandates anti-termite treatment for buildings in termite-active regions)
• NBC 2016 Part 7 — Constructional Practices (specific protocols for treatment)
• CPWD Specifications 2019 — Volume on Termite Treatment (procurement standard)
• IS 401:2001 — Code of Practice for Preservation of Timber (sister code for treatment of timber elements)
• IS 1141:1993 — Seasoning of Timber
• CIBSR (Central Institute of Building Survey & Research) — research-grade guidelines on termite control

IS 6313 Part 1:2000 is 25 years old and overdue for revision. Key gaps in the 2000 edition: - Newer chemicals (imidacloprid, bifenthrin, fipronil) which are more termite-specific and less toxic to non-target organisms — not formally codified in IS 6313 - Physical barrier methods (stainless steel mesh, particle-size barriers using crushed basalt grit) — covered only in Annex; practical guidance limited - Green-building integration — LEED / IGBC / GRIHA give credits for non-chemical termite management; IS 6313 doesn't address this pathway in detail

Indian market reality: - Major pest-control firms (Truly Nolen, Rentokil PCI, Hicare, Pest Control India) deliver IS 6313 Part 1 protocols consistently. Cost: ₹15-25/sq ft of building footprint for the full 5-stage treatment with 5-year warranty. - Small local pest-control firms vary wildly in quality. Chemical sourcing, dilution, application all suspect. Cost: ₹3-8/sq ft — but warranty often nominal. - In-house treatment by main contractor — common on smaller projects to save cost. Quality depends entirely on PMC supervision. Cost: ₹2-5/sq ft.

For projects > 5,000 sq ft / ₹50 lakh value: always engage a BIS-licensed pest-control firm with documented IS 6313 Part 1 protocol and 5-year warranty. The total cost is small (~0.2-0.5% of construction cost) for the structural-integrity protection it provides over the 50-year building life.

Environmental angle: chlorpyriphos has come under WHO and EU restrictions due to neurotoxicity concerns. India's CIBRC has restricted use to professional pest-control only (no over-the-counter sales). For sensitive sites (schools, hospitals, food-processing facilities), specify bifenthrin or imidacloprid instead — less mammalian toxicity, comparable termite efficacy. IS 6313 doesn't formally specify these alternatives but their use is widely accepted in modern Indian practice.