IS 1200 – Methods of Measurement - Overview
Indian Standard for Measurement
What is IS 1200?
Full Title: IS 1200 - Methods of Measurement of
Building and Civil Engineering Works
Published By: Bureau of Indian Standards (BIS)
Purpose: Standardize measurement methods for
construction work to ensure uniformity and avoid disputes.
Structure: 28 Parts covering different work
categories
Legal Status:
- Referenced
in government contracts (mandatory)
- Reference
standard in private contracts (best practice)
- Basis
for arbitration/disputes on quantities
IS 1200 - 28 Parts:
Part 1 (1992): Earthwork
Part 2 (1974): Piling
Part 3 (1965): Cement Concrete Work (Superseded by Part 5)
Part 4 (1967): Structural Steel Work
Part 5 (1982): Concrete Work (RCC, Plain Concrete)
Part 6 (1972): Masonry (Brickwork, Stonework, Blockwork)
Part 7 (1972): Roofing and Sheeting (Tiles, Metal sheets)
Part 8 (1981): Doors, Windows and Ventilators
Part 9 (1992): Plastering, Pointing and Finishing
Part 10 (1992): Water Proofing and Damp Proofing
Part 11 (1993): Drainage Work
Part 12 (1982): Road Work
Part 13 (1983): Railway Track Work
Part 14 (1967): Underground Sewer and Water Supply
Part 15 (1968): Canal Work
Part 16 (1974): Electrical Work
Part 17 (1977): Glazing Work
Part 18 (1995): White Washing, Colour Washing, Distempering
Part 19 (1981): Reinforcement for RCC Work
Part 20 (1982): Finishing of Floors and Other Surfaces
Part 21 (1995): Dam, Aqueduct and Reservoir
Part 22 (1982): Wood Work (Carpentry and Joinery)
Part 23 (1974): Painting
Part 24 (1981): Timber Treatment
Part 25 (1982): Plumbing and Sanitary Installations
Part 26 (1983): Bridge Work
Part 27 (1987): Insulation Work (Thermal, Acoustic)
Part 28 (1981): Asbestos Cement Works
Key Parts for Building Construction:
Most Used (90% of building work):
- Part
1: Earthwork (excavation, filling, grading)
- Part
5: Concrete work (RCC, PCC)
- Part
6: Masonry (brickwork, blockwork)
- Part
9: Plastering and pointing
- Part
10: Waterproofing
- Part
19: Reinforcement (steel bars)
- Part
20: Flooring
- Part
23: Painting
Specialized (as needed):
- Part
2: Piling (if foundation has piles)
- Part
8: Doors and windows (if measured separately)
- Part
22: Woodwork (if significant carpentry)
- Part
25: Plumbing (sanitary, water supply)
How IS 1200 Works:
Each Part Contains:
- Scope:
What work is covered
- Units
of Measurement: m, m², m³, kg, nos, etc.
- General
Rules: What is included in measurement
- Specific
Rules: Item-wise measurement methods
- Deductions:
What openings/items to deduct
- Exclusions:
What is NOT measured
- Examples:
Illustrative calculations
Example - IS 1200 Part 6 (Brickwork):
Scope: Measurement of brick masonry in walls,
columns, arches, etc.
Unit: Cubic meter (m³) for rate contracts Square
meter (m²) for item rate contracts (9" wall, 4.5" wall separately)
General Rules:
1. Measured in cubic meters (length × height × thickness)
2. No deduction for:
- Openings up to
0.1 m² each
- Wooden or steel
members up to 0.05 m² cross-section
3. Deduct in full:
- Openings
exceeding 0.1 m² each
- Bearings of
beams, lintels
4. Add separately:
- Raking,
corbelling, curved work (if >5% extra)
5. Mortar is included (not measured separately)
6. Scaffolding is included (not measured separately)
What This Means:
Example: Wall 5m long × 3m high × 0.23m (9") thick with
1 door opening 1m × 2m
Gross volume: 5 × 3 × 0.23 = 3.45 m³
Door opening: 1 × 2 × 0.23 = 0.46 m² (exceeds 0.1 m², so
deduct)
Net brickwork: 3.45 - 0.46 = 2.99 m³
Payment: 2.99 m³ @ rate per cum
Importance of Following IS 1200:
Legal:
- Contract
clause: "Measurement as per IS 1200"
- Disputes
resolved based on IS 1200 interpretation
- Arbitrator's
decision references IS 1200
Practical:
- Uniform
understanding (contractor, engineer, client)
- No
ambiguity in what's included/excluded
- Fair
payment (standardized method)
Financial:
- Incorrect
measurement = Incorrect payment
- Knowing
IS 1200 = Claiming what's rightfully yours
- Example:
Forgetting to claim raking in brickwork = 5-8% loss
IS 1200 PART 1 - EARTHWORK
Title: Measurement of Excavation and Filling
Scope: All earthwork including excavation, filling,
grading, leveling, ramming.
Unit of Measurement: Cubic meter (m³)
Critical Rule 1: In-Situ Measurement
Earthwork is ALWAYS measured in the INITIAL STATE (before
excavation)
Example:
Excavation required:
1,000 m³ (in-situ, before digging)
After excavation,
soil swells to: 1,300 m³ (loose state, 30% swell)
Payment: For 1,000
m³ ONLY
You do NOT get paid
for swell volume!
Rationale: Payment for actual work, not bulking due
to loosening.
Critical Rule 2: Classification of Soil
IS 1200 Part 1 recognizes different soil types:
1. Ordinary Soil (Earth)
- Easy to dig with
pick and shovel
- Example: Clay,
loamy soil, sand
2. Hard Soil
- Requires pick,
crowbar, mechanical equipment
- Example: Gravel,
dense clay, soft murrum
3. Soft Rock (Disintegrated)
- Requires
mechanical equipment, some blasting
- Example:
Weathered rock, laterite
4. Hard Rock
- Requires blasting
- Example: Granite,
basalt, hard sedimentary rock
Why It Matters: Different rates for different soil
types (rock excavation costs 3-5× ordinary soil)
Payment:
If BOQ says: "Excavation in ordinary soil" but you
encounter rock
→
Rate revision claim (extra item rate for rock)
→
Dispute avoided if soil properly classified upfront
Measurement Rules - Excavation:
1. Foundation Excavation:
Measured: Length × Width × Depth (all in meters)
Width measured: Trench width (foundation + working space)
Foundation width: As
per drawing
Working space: 500mm
each side (typical)
Total width =
Foundation width + 1000mm
Depth measured:
From NGL (Natural
Ground Level) to formation level
OR as specified in
drawings
Example:
Foundation: 10m long
× 1m wide × 2m deep (from NGL)
Working space: 0.5m
each side
Measured width: 1 +
0.5 + 0.5 = 2m
Excavation quantity:
10 × 2 × 2 = 40 m³
2. Basement Excavation:
Measured: Gross area × depth
Deductions:
- Existing
structures to remain (if any)
- Trees beyond 0.3m
girth (measured separately)
No deduction for:
- Internal walls
(excavate full basement, then build walls)
- Columns, pillar
bases
Example:
Basement: 20m × 15m
× 3m deep
Quantity: 20 × 15 ×
3 = 900 m³
3. Removal of Excavated Material:
Measured separately if distance > 50m
Item description specifies:
- "Excavation
and disposal within 50m"
- "Removal
beyond 50m for every additional 50m or part thereof"
Lead distance: Horizontal distance from excavation to
disposal point
Example:
Excavation: 1,000 m³
Disposal point: 180m
away
Items to measure:
1. Excavation:
1,000 m³ (up to 50m included)
2. Extra lead
(50-100m): 1,000 m³
3. Extra lead
(100-150m): 1,000 m³
4. Extra lead
(150-200m): 1,000 m³
Measurement Rules - Filling:
1. Filling Under Floors:
Measured: Area × Average thickness
Include:
- Compaction (in
measurement description, e.g., "in layers of 200mm")
- Watering and
ramming
Exclude:
- Earth removed and
re-used (filling with excavated earth)
- Measure only EXTRA
earth brought from outside
Example:
Floor area: 100 m² ×
0.6m thick filling
Excavated available:
50 m³
Required: 100 × 0.6
= 60 m³
Measure filling with
excavated earth: 50 m³ (free, just spreading cost)
Measure filling with
brought earth: 10 m³ (material + transport cost)
2. Backfilling Trenches:
Measured: Trench volume - Foundation volume
Example:
Trench excavation:
40 m³ (from earlier example)
Foundation
(masonry/concrete): 10m × 1m × 0.5m = 5 m³
Backfilling
required: 40 - 5 = 35 m³
If excavated soil
re-used: 35 m³ backfill with excavated earth
If not suitable: 35
m³ backfill with selected soil (brought from outside)
Common Mistakes - Earthwork:
Mistake 1: Paying for Swell
Wrong: Measure after excavation (1,300 m³ loose)
Right: Measure in-situ before excavation (1,000 m³)
Loss if wrong: 30% overpayment
Mistake 2: Not Classifying Soil
Wrong: All excavation in "ordinary soil" (but 30%
is rock)
Right: Separate measurement - 700 m³ ordinary, 300 m³ rock
Impact: Rock costs 3× more, ₹(300 × ₹800) = ₹2.4 lakhs extra
deserved
Mistake 3: Deducting Small Openings
Wrong: Deduct column pits from basement excavation
Right: No deduction (excavate full basement)
Loss if wrong: Under-measurement, lower payment
Mistake 4: Ignoring Working Space
Wrong: Foundation trench = foundation width only (1m)
Right: Foundation + working space (2m)
Loss if wrong: 50% under-measurement!
IS 1200 PART 5 - CONCRETE WORK
Title: Measurement of RCC and Plain Concrete
Scope: All concrete work - plain cement concrete
(PCC), reinforced cement concrete (RCC), pre-stressed concrete.
Unit of Measurement: Cubic meter (m³)
Critical Rule 1: Gross Volume
Concrete is measured GROSS (including embedded items)
Include in concrete volume:
- Reinforcement
steel (bars, mesh)
- Embedded pipes,
conduits
- Embedded anchor
bolts, inserts
- Formwork
(shuttering) is not deducted
Do NOT deduct:
- Reinforcement
(even though it occupies space)
- Small embedments
Example:
RCC Column: 0.3m ×
0.4m × 3.5m
Steel inside: 8 nos
20mm dia bars + stirrups (~ 0.01 m³)
Measured concrete:
0.3 × 0.4 × 3.5 = 0.42 m³ (gross, no deduction for steel)
Reinforcement
measured separately as per Part 19 (in kg)
Rationale: Simplicity - deducting small volumes
creates complexity without significant accuracy gain.
Critical Rule 2: Formwork Included
Unless specified otherwise, formwork is INCLUDED in concrete
rate
Measurement description specifies:
- "Including
cost of formwork and its removal"
- OR separate item:
"Providing and removing formwork to ___"
For rate analysis:
If formwork NOT
separate, include ₹450-800/m³ in concrete rate
If formwork
separate, exclude from concrete rate
Measurement Rules - Foundations:
1. Plain Cement Concrete (PCC) in Foundation:
Measured: Length × Width × Thickness
Example:
Foundation: 10m long
× 2m wide × 0.15m thick (PCC bed)
Quantity: 10 × 2 ×
0.15 = 3.0 m³
Item description:
"Plain cement concrete M15 grade in foundation
including formwork,
compaction, curing as per IS 456"
2. RCC Footings:
Measured: As per individual footing dimensions
For isolated footings:
Each footing: Length
× Width × Depth
Total: Sum of all
footings
Example:
10 footings, each 2m
× 2m × 0.5m
Per footing: 2 × 2 ×
0.5 = 2.0 m³
Total: 10 × 2.0 = 20
m³
Measurement Rules - Columns:
Measured: Cross-section × Height
Height measured:
From: Top of
footing/plinth
To: Soffit of beam
above (underside of beam)
NOT to top of beam
(that's part of beam)
Example:
Column: 0.3m × 0.4m
cross-section
Number of columns:
20
Floor height: 3.5m
(floor to soffit of beam)
Per column: 0.3 ×
0.4 × 3.5 = 0.42 m³
Total G.F. columns:
20 × 0.42 = 8.4 m³
Item: "RCC M30
in columns including formwork" = 8.4 m³
Deductions:
No deduction for:
- Reinforcement
steel
- Openings/recesses
< 0.1 m² cross-section
Deduct:
- Large
recesses/openings > 0.1 m² (rare in columns)
Measurement Rules - Beams:
Measured: Cross-section × Length
Length measured:
For independent
beams: Center to center of supports
For continuous
beams: Full length (don't deduct column widths)
Height measured:
From: Top of slab
(if monolithic)
To: Soffit of beam
If beam is
independent: Full depth
Example:
Beam: 0.3m wide ×
0.5m deep (below slab)
Length: 5m (between
column centers)
Number: 10 beams
Per beam: 0.3 × 0.5
× 5 = 0.75 m³
Total: 10 × 0.75 =
7.5 m³
Monolithic Beam-Slab:
Beam and slab cast together (most modern construction)
Measure beam:
Width × Depth
(excluding slab thickness) × Length
Measure slab:
Area × Thickness
(full area, no deduction for beam width)
Example:
Room: 5m × 4m
Slab: 0.15m thick
Beam (on all 4
sides): 0.3m wide × 0.5m deep
Slab: 5 × 4 × 0.15 =
3.0 m³
Beams:
2 beams (5m long):
2 × (0.3 × 0.5 × 5) = 1.5 m³
2 beams (4m long):
2 × (0.3 × 0.5 × 4) = 1.2 m³
Total beams: 2.7
m³
Total concrete: 3.0
+ 2.7 = 5.7 m³
Measurement Rules - Slabs:
Measured: Area × Thickness
Area: Gross area (no deduction for beams if monolithic)
Deductions:
- Openings > 0.5
m² (e.g., staircase opening, lift well)
- Skylights, large
vents
No deduction for:
- Openings < 0.5
m² (small vents, pipes)
- Beams (if
monolithic)
- Columns passing
through
Example:
Slab: 10m × 8m ×
0.15m thick
Opening (staircase):
2m × 1.5m = 3 m² (deduct)
Small vent: 0.4m ×
0.4m = 0.16 m² (don't deduct)
Gross: 10 × 8 = 80
m²
Less opening: 3 m²
Net area: 77 m²
Quantity: 77 × 0.15
= 11.55 m³
Measurement Rules - Special Items:
1. Sunken Slabs:
Measured separately (different level)
Example:
Bathroom slab sunken
by 300mm for waterproofing
Area: 2m × 1.5m
Thickness: 0.15m
Sunk depth: 0.3m
Regular slab: 2 ×
1.5 × 0.15 = 0.45 m³
Plus sides: 2(2 +
1.5) × 0.3 × 0.15 = 0.315 m³
OR measure as
separate item: "RCC in sunken slab" = 0.77 m³
2. Staircases:
Measured: Developed area (following slope) × Average
thickness
OR: Volume calculation (waist slab + treads)
Example:
Flight: 10 treads,
0.25m tread, 0.15m rise
Width: 1.2m
Waist slab
thickness: 0.15m
Slope length:
√(10×0.25)² + (10×0.15)² = 2.92m
Area: 2.92 × 1.2 =
3.5 m²
Concrete: 3.5 × 0.15
= 0.525 m³
Plus treads volume
if separate
3. Chajjas, Sunshades:
Measured: Area × Thickness
Include projection in area
Example:
Chajja: 5m long ×
0.6m projection × 0.1m thick
Quantity: 5 × 0.6 ×
0.1 = 0.3 m³
IS 1200 PART 6 - MASONRY WORK
Title: Measurement of Brickwork and Blockwork
Scope: Brick masonry, stone masonry, cement block
masonry in walls, columns, arches.
Unit of Measurement: Cubic meter (m³) for rate
contracts
OR Square meter (m²) for item rate contracts specifying wall thickness
Critical Rule 1: Openings Deduction
Deduct openings ONLY if each exceeds 0.1 m²
Examples:
Door opening: 1m × 2m = 2 m² →
DEDUCT (>0.1 m²)
Window opening: 1.2m × 1.5m = 1.8 m² → DEDUCT (>0.1 m²)
Small vent: 0.3m × 0.3m = 0.09 m² → DON'T DEDUCT (<0.1 m²)
Pipe hole: 0.15m × 0.2m = 0.03 m² → DON'T DEDUCT (<0.1 m²)
Rationale:
Small openings
require cutting, wastage →
labor compensates for material saved
Critical Rule 2: Mortar Included
Brickwork measurement includes mortar
Item description: "Brickwork in CM 1:6" means:
- Bricks
- Cement mortar 1:6
- Laying, jointing
- Scaffolding
- Curing
Do NOT measure cement and sand separately for mortar
(Already included in brickwork rate)
Measurement Rules - Walls:
1. External Walls:
Measured: Length × Height × Thickness
Length:
Outside to outside
(for external walls)
OR centerline method
(explained later)
Height:
From: Top of
plinth/floor
To: Bottom of roof
slab/ceiling
Thickness:
As per specification
(9", 4.5", 13.5")
In meters: 9" =
0.23m, 4.5" = 0.115m, 13.5" = 0.345m
Example:
External wall: 15m
long × 3m high × 0.23m (9") thick
2 windows: Each 1.2m
× 1.5m = 1.8 m² (DEDUCT)
1 door: 1m × 2m = 2
m² (DEDUCT)
Gross: 15 × 3 × 0.23
= 10.35 m³
Less windows: 2 ×
(1.2 × 1.5 × 0.23) = 0.828 m³
Less door: 1 × 2 × 0.23 = 0.46 m³ Net brickwork: 10.35 -
0.828 - 0.46 = 9.062 m³
2. Internal Walls:
Measured: Length × Height × Thickness
Length: Wall to wall (for partition walls) OR centerline of
walls
Deductions:
- Door
openings (internal doors typically 0.9m × 2m = 1.8 m² → DEDUCT)
Example: Internal wall: 4m long × 3m high × 0.115m
(4.5") thick 1 door: 0.9m × 2m = 1.8 m²
Gross: 4 × 3 × 0.115 = 1.38 m³ Less door: 0.9 × 2 × 0.115 =
0.207 m³ Net: 1.17 m³
Centerline Method (Shortcut for Complex Plans):
Concept:
Instead of calculating each wall separately with junctions,
use total centerline length.
Formula:
Brickwork = Centerline length × Height × Thickness
Example:
Room: 5m × 4m (external dimensions) Wall thickness: 0.23m
(9") Height: 3m No openings
Method 1 - Individual walls: 2 walls (5m long): 2 × 5 × 3 ×
0.23 = 6.9 m³ 2 walls (4m long): 2 × 4 × 3 × 0.23 = 5.52 m³ BUT: Overlap at
corners (counted twice) Correction needed: Complex
Method 2 - Centerline: External perimeter: 2(5 + 4) = 18m
Centerline: 18m (measured at center of wall)
Brickwork: 18 × 3 × 0.23 = 12.42 m³ ✓
Accurate
When to Use:
- Complex plans with many walls
- Multiple rooms with junctions
- Saves time, reduces errors
When NOT to Use:
- Walls of different thickness (need separate calculation)
- Many openings (deduct individually anyway)
Measurement Rules - Special Items:
1. Raking/Corbelling:
Measured separately if significant (>5% extra)
Raking: Sloped brickwork (gables, ramps) Corbelling:
Projecting courses
Example: Gable end: Triangular brickwork Base: 5m, Height:
2m, Thickness: 0.23m Area: 0.5 × 5 × 2 = 5 m² Volume: 5 × 0.23 = 1.15 m³
Item: "Raking in brickwork" = 1.15 m³ @ higher
rate (+15-20%)
2. Arches:
Measured: Developed length × Width × Thickness
Developed length: Following curve
Example: Semi-circular arch over door Span: 1m, Width (wall
thickness): 0.23m Thickness of arch: 0.23m
Developed length: π × 1 ÷ 2 = 1.57m Volume: 1.57 × 0.23 ×
0.23 = 0.083 m³
3. Curved Walls:
Measured: Curved length × Height × Thickness
Use flexible tape to measure curve OR calculate from radius
Extra rate for curvature (more labor, wastage)
Common Mistakes - Masonry:
Mistake 1: Deducting Small Openings
Wrong: Deduct every vent, pipe hole Right: Deduct only
openings >0.1 m² Impact: Under-measurement by 2-5%
Mistake 2: Measuring Mortar Separately
Wrong: Measure bricks, then cement, then sand for mortar
Right: Brickwork includes everything (just measure brickwork) Impact:
Confusion, potential double-counting
Mistake 3: Forgetting Corner Overlaps
Wrong: Measure all 4 walls full length → Corners counted twice
Right: Use centerline method OR deduct overlap Impact: Over-measurement by 5-8%
Mistake 4: Wrong Thickness Conversion
Wrong: 9" wall = 0.25m (rough approximation) Right:
9" = 9 × 0.0254m = 0.2286m ≈ 0.23m (accurate) Impact: 8% error in
thickness → 8% error
in quantity
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