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RAJUK Setbacks · FAR · Net Footprint · Katha & Decimal
Plot Size Calculator
Calculate net buildable footprint after setbacks, ground coverage ratio, FAR-based maximum built-up area, and total floor area. Pre-filled with RAJUK minimum setbacks for Dhaka residential plots. Works for any city — update setbacks for CDA, KDA, RDA.
Setback defaults: RAJUK DAP minimums (Front 5 ft · Sides 3.3 ft · Rear 5 ft). Last reviewed: May 2026.
How to Use
- 1Enter plot width (frontage) and depth in feet or metres.
- 2Adjust setbacks if your authority requires different minimums — RAJUK defaults are pre-filled.
- 3Enter FAR (from your RAJUK or local authority approval) to see maximum built-up area.
- 4Enter number of floors to calculate total floor area from footprint.
- 5Review gross area, net footprint, coverage ratio, and Katha/Decimal equivalents.
Example Calculation
- Plot: 30 ft wide × 60 ft deep
- Gross area: 1,800 sqft = 2.5 Katha
- Setbacks: front 5, sides 3.3, rear 5
- Net footprint: (30−6.6) × (60−10) = 23.4 × 50 = 1,170 sqft
- Coverage: 65% (slightly over RAJUK limit)
- FAR 2.5 → max built-up: 4,500 sqft
Tip: reduce side setbacks or use FAR to plan floors — coverage ratio guides approval chances.
Formula Used
Gross area = Width × Depth
Net width = Width − Left − Right setbacks
Net depth = Depth − Front − Rear setbacks
Footprint = Net width × Net depth
Coverage = Footprint ÷ Gross × 100%
FAR area = Gross area × FAR
Floor area = Footprint × Floors
Metres converted to feet at 1m = 3.28084 ft before calculation.
RAJUK Setback & FAR Reference
Minimum setbacks and FAR limits for residential plots in Dhaka Metropolitan Area per RAJUK DAP (Detailed Area Plan). Verify with your specific approval letter — values vary by zone.
| Plot Size | Front Setback | Side Setbacks | Rear Setback | Max FAR | Max Coverage |
|---|---|---|---|---|---|
| Under 3 Katha (< 2,160 sqft) | 5 ft (1.5m) | 3.3 ft (1m) each | 5 ft (1.5m) | 2.5 | 60% |
| 3–5 Katha (2,160–3,600 sqft) | 5 ft (1.5m) | 3.3 ft (1m) each | 5 ft (1.5m) | 2.5 | 60% |
| 5–10 Katha (3,600–7,200 sqft) | 7 ft (2.1m) | 5 ft (1.5m) each | 7 ft (2.1m) | 3.0 | 55% |
| Above 10 Katha (> 7,200 sqft) | 10 ft (3m) | 6.6 ft (2m) each | 10 ft (3m) | 3.5 | 50% |
⚠️ These are indicative RAJUK DAP minimums. Actual approval depends on zone type (residential, commercial, mixed), road width, and specific plot conditions. Always get a written approval from RAJUK before starting construction.
References & Data Sources
- RAJUK (Rajdhani Unnayan Kartripakkha) — Detailed Area Plan (DAP) 2022–2035; setback requirements, FAR limits, and ground coverage ratios for Dhaka Metropolitan Area. rajuk.gov.bd
- Bangladesh National Building Code (BNBC) 2020 — Chapter 3: Land Use and Building Regulations; setback and coverage requirements for residential construction.
- CDA (Chittagong Development Authority) — Building Rules 2011; FAR and setback standards for Chittagong Metropolitan Area. cda.gov.bd
- Ministry of Housing and Public Works, Government of Bangladesh — Building Construction Act 1952 (amended); general framework for building approvals and setback compliance.
FAR and setback values are for general reference. Regulations change — verify current figures with your local development authority before any construction activity. Last reviewed: May 2026.
Plot Planning Tips for Bangladesh
- 1RAJUK setback defaults shown (5 ft front, 3.3 ft sides, 5 ft rear) are minimums — for plots above 5 Katha, larger setbacks apply under DAP rules
- 2Ground coverage above 60% will likely fail RAJUK approval — watch the coverage ratio in the results as you adjust setbacks
- 3FAR determines your total built-up area limit — enter the FAR from your RAJUK approval or local plan to see the maximum permissible construction
- 4For narrow plots (under 15 ft wide), the 3.3 ft side setbacks on each side leave very little buildable width — verify with an architect before purchase
- 5The 'number of floors' field calculates total floor area from the footprint — this is not the same as FAR-limited built-up area; use both figures for planning
- 6CDA (Chittagong), KDA (Khulna), RDA (Rajshahi), and BSCIC zones have different FAR and setback rules — clear the defaults and enter your authority's figures
Frequently Asked Questions
What is FAR / FSI and how does it affect my building?
FAR (Floor Area Ratio) or FSI (Floor Space Index) is the ratio of total built-up floor area to the gross plot area. RAJUK sets FAR limits by zone — typically 2.5–3.5 for residential areas in Dhaka. A 3,000 sqft plot with FAR 2.5 allows a maximum of 7,500 sqft of total built-up area across all floors. Exceeding the FAR is illegal and can result in demolition orders.
What are the standard RAJUK setbacks for residential plots in Dhaka?
RAJUK DAP (Detailed Area Plan) setback minimums for standard residential plots: Front setback 5 ft (1.5m) on roads under 20 ft wide, up to 7 ft on wider roads. Side setbacks 3.3 ft (1m) each. Rear setback 5 ft. These are minimums — for larger plots above 5 Katha, setbacks increase. Always check the latest RAJUK approval letter for your specific plot.
What is the ground coverage ratio?
Ground coverage is the percentage of the gross plot area occupied by the building footprint. RAJUK limits ground coverage to 50–60% for most residential zones. The calculator shows this automatically based on your setback inputs — if it exceeds 60%, your setbacks may be too small for RAJUK approval.
How do I calculate buildable area for an L-shaped plot?
For L-shaped plots, apply setbacks to the outer boundary first to get the net buildable polygon. The rectangular approximation used by this calculator works for simple plots — for irregular shapes, a licensed surveyor should prepare a setback layout drawing, which RAJUK requires for building plan submission.
What is the difference between gross plot area and net buildable footprint?
Gross plot area is the total land area from boundary to boundary as recorded in the deed. Net buildable footprint is what remains after deducting the mandatory setbacks on all four sides. This is the maximum ground floor area you can build. Upper floors can extend closer to the boundary in some cases — subject to RAJUK approval.
Do CDA (Chittagong) and KDA (Khulna) use the same setback rules as RAJUK?
No — CDA and KDA have their own development authority rules. CDA generally follows similar principles but the specific FAR, coverage ratio, and setback distances differ. This calculator pre-fills RAJUK defaults. If your plot is under CDA, KDA, or another authority, update the setback fields manually to match your authority's requirements.