1
Area Conversion
effectiveArea = inputArea × conversionFactor Kerala Building Setback Calculator
Calculate front, rear, and side setbacks per KMBR 2019/2025. Enter your plot area in any unit — we'll convert automatically.
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Liability Disclaimer: For Estimation Only
(Click to Read)
This tool provides estimates based on general algorithms. It does NOT constitute professional engineering advice. Structures must be verified by a licensed engineer per IS Codes. By using this tool, you agree to indemnify K-First against any financial losses.
1 cent = 40.468 sq.m | 1 are = 100 sq.m | Threshold: 125 sq.m ≈ 3.09 cents
Kerala Setback Norms: Rule 27 vs Rule 87
Source: KMBR 2019 + Amendment 2025
| Setback Type | Rule 87 (≥125 sq.m) | Rule 27 (<125 sq.m) | Notes |
|---|---|---|---|
| Front Yard | 3.0m | 1.8m | NH/SH/District roads enforce 3.0m min |
| Rear Yard | 1.5m (+ height modifier) | 1.0m (avg), 0.5m min | +0.5m per 3m above 10m height |
| Side Yards | 1.0m each (+ height modifier) | 0.6m each | <1.0m needs neighbor consent |
| Max Height | Per FSI/coverage | 10m (3 floors) | Rule 61 blocks >10m for small plots |
| Commercial | No limit | 200 sq.m built-up max | Rule 61(2) restriction |
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Small Plot Exemption: Plots under 125 sq.m (≈3.09
cents) qualify for Rule 27 relaxed setbacks, maximizing buildable
area.
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Road Authority Override: NH/SH/District roads enforce
3.0m minimum regardless of plot size (Kerala Land Acquisition Act
Section 77).
▶ Legal References & Downloads
KMBR 2019 S.R.O. No. 777/99 (November 7, 2019)
KMBR Amendment 2025 S.R.O. No. 297/2025 (October 29, 2025)
Kerala Land Acquisition Act Section 77 (1963)
How to Calculate Building Setbacks in Kerala
Setback Calculation Logic (KMBR 2019/2025)
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Small Plot Detection
isSmallPlot = effectiveArea < 125 sq.m 3
Height Modifier (Rule 87 only)
extraSetback = floor((height - 10) / 3) × 0.5m 4
Road Override
frontSetback = max(baseSetback, roadMinimum) Worked Examples
Small Plot on State Highway
2.8 cents plot abutting SH. Height: 9m.
Small Plot on State Highway
2.8 cents plot abutting SH. Height: 9m.
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Convert to Sq.m
2.8 × 40.468 = 113.31 sq.m 2
Small Plot Check
113.31 < 125 → YES (Rule 27) 3
Base Setbacks
Front: 1.8m, Rear: 1.0m, Sides: 0.6m 4
Road Override (SH)
Front = max(1.8, 3.0) = 3.0m ⚠️ Result: Front: 3.0m, Rear: 1.0m, Sides: 0.6m
PWD Risk: Land Acquisition Act overrides Rule 27 front setback
Standard Plot with Height Modifier
5 cents plot on local road. Height: 16m.
Standard Plot with Height Modifier
5 cents plot on local road. Height: 16m.
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Convert to Sq.m
5.0 × 40.468 = 202.34 sq.m 2
Standard Plot Check
202.34 ≥ 125 → Rule 87 3
Height Modifier
floor((16-10)/3) × 0.5 = 1.0m extra 4
Final Setbacks
Rear: 1.5+1.0=2.5m, Sides: 1.0+1.0=2.0m Result: Front: 3.0m, Rear: 2.5m, Sides: 2.0m each
Height modifier adds 1.0m to rear and sides
Understanding KMBR Setback Requirements
Building setbacks in Kerala are governed by the Kerala Municipality Building Rules 2019 (KMBR) for urban areas and Kerala Panchayat Building Rules 2019 (KPBR) for rural areas.
Key Factors Affecting Setbacks:
- Total Plot Area — Under 125 sq.m qualifies for Rule 27 exemption
- Building Height — Taller buildings (>10m) need additional setback
- Road Type — NH/SH/District roads enforce 3m minimum
Which Unit to Use?
Square meters (sq.m) is the mandatory unit in K-Smart and Sanketham permit software. If your deed shows cents, multiply by 40.468 to convert. This calculator handles conversion automatically.
Irregular Plots
For L-shaped or triangular plots, enter only your total area (from deed). Setback rules apply based on total area, not shape. However, buildable area calculation requires an architect for irregular geometries.
FAQs
What unit should I use for plot area in Kerala? ▼
Square meters (sq.m) is the mandatory unit in K-Smart and Sanketham permit software. If your deed shows cents, multiply by 40.468 to convert. This calculator handles the conversion automatically.
What is the Small Plot Exemption (Rule 27)? ▼
Rule 27 of KMBR/KPBR 2019 provides relaxed setbacks for plots under 125 sq.m (≈3.09 cents): Front 1.8m, Rear 1.0m, Sides 0.6m. This helps maximize buildable area on constrained urban plots.
Why does my 1.8m front setback become 3.0m on a highway? ▼
Kerala Land Acquisition Act 1963 Section 77 mandates 3m from NH/SH/District road centerlines. This overrides KMBR Rule 27. LSGD may approve 1.8m, but PWD/NHAI can demand demolition post-construction.
Can I use this calculator for irregular (L-shaped) plots? ▼
Yes! Enter your total plot area (from deed/survey). Setback rules apply based on total area, not shape. However, buildable area calculation requires an architect for irregular plots.
What if I don't know my plot dimensions? ▼
No problem! Dimensions are optional in this calculator. Enter only your total plot area to get setback requirements. The visual diagram will be hidden if dimensions are not provided.