Kenya Construction Cost Calculator & Mafundi Material Quantification

Finish Level	Nairobi	Other Urban	Rural / Semi-urban
Low-cost (basic finishing)	KES 28,000–35,000	KES 22,000–28,000	KES 18,000–24,000
Standard (mid-range)	KES 38,000–55,000	KES 32,000–45,000	KES 26,000–38,000
High-end / Luxury	KES 60,000–100,000+	KES 55,000–85,000	KES 45,000–70,000

🧱

Blinding Concrete

Thin concrete layer beneath strip footings — Mix Ratio 1:3:6

Wet Volume = Perimeter × Width × Thickness
Dry Volume = Wet Volume × 1.54 (voids factor)
Cement Bags = (Dry Vol × 1 / (1+3+6)) / 0.035 m³ per bag
Sand = (Dry Vol × 3 / 10) × 1.6 t/m³
Ballast = (Dry Vol × 6 / 10) × 1.65 t/m³

Perimeter (m) *

Width (m) default 0.60

Thickness (m) default 0.05

Mix Ratio default 1:3:6

📊 Blinding Concrete Results Mix 1:3:6

📐 Volumes

Wet Volume

—

m³

Dry Volume (×1.54)

—

m³

🏗 Materials Required

Cement (50 kg bags)
—
bags

Sand
—
tonnes

Ballast / Aggregate
—
tonnes

Wastage Applied

—

% on quantities

Calculation Steps

⚠ Verify lengths from approved drawings. Add 5–10% wastage for on-site losses. Consult a QS before procurement.

⬛

Strip Footing Concrete

Reinforced strip foundation — Mix Ratio 1:2:4

Wet Volume = Length × Width × Thickness
Dry Volume = Wet Volume × 1.54
Cement Bags = (Dry Vol / (1+2+4)) × 1 × (1000/50) × density
Sand = (Dry Vol × 2 / 7) × 1.6 t/m³
Ballast = (Dry Vol × 4 / 7) × 1.65 t/m³

Length (m) *

Width (m) default 0.60

Thickness (m) *

Concrete Class

📊 Strip Footing Results Mix 1:2:4

📐 Volumes

Wet Volume

—

m³

Dry Volume (×1.54)

—

m³

🏗 Materials Required

Cement (50 kg bags)
—
bags

Sand
—
tonnes

Ballast / Aggregate
—
tonnes

Wastage Applied

—

%

Calculation Steps

⚠ Include rebar per structural engineer's specification. This covers concrete only.

🏛

Column Concrete

Rectangular reinforced concrete columns — enter one typical column size and quantity.

Wet Volume = Column Width × Column Length × Column Height × Number of Columns
Dry Volume = Wet Volume × 1.54 (voids factor)
Cement Bags = (Dry Vol × cement ratio / total ratio ÷ 0.035 m³ per bag)
Sand = Dry Vol × sand ratio / total ratio × 1.60 t/m³
Ballast = Dry Vol × aggregate ratio / total ratio × 1.65 t/m³

Column Width (m) *

Column Length (m) *

Column Height (m) *

Number of Columns *

Concrete Class

📊 Column Concrete Results Mix 1:2:4

📐 Volumes

Single Column Volume

—

m³

Total Wet Volume

—

m³

Dry Volume (×1.54)

—

m³

Concrete Class

—

ratio

🏗 Materials Required

Cement (50 kg bags)
—
bags

Sand
—
tonnes

Ballast / Aggregate
—
tonnes

Wastage Applied

—

% on quantities

Calculation Steps

⚠ This covers concrete only. Reinforcement steel, formwork, and column starter bars must be designed by a structural engineer.

🧱

Beam Concrete

Add Beam 1, Beam 2 and more beams. Each beam uses width, depth, length and concrete class.

Beam Wet Volume = Width × Depth × Length
Dry Volume = Wet Volume × 1.54
Total Materials = Sum of all beam volumes using selected concrete class

📊 Beam Concrete Results All beams

📐 Volumes

Total Wet Volume

—

m³

Dry Volume (×1.54)

—

m³

Concrete Class

—

ratio

Beam Count

—

beams

🏗 Materials Required

Cement (50 kg bags)
—
bags

Sand
—
tonnes

Ballast / Aggregate
—
tonnes

Wastage Applied

—

% on quantities

Calculation Steps

⚠ This covers concrete only. Beam reinforcement, stirrups, formwork and support conditions require structural design.

⬛

Column Base Concrete

Rectangular column bases/footing pads — length, width, depth, class and quantity.

Wet Volume = Base Length × Base Width × Base Depth × Number of Bases
Dry Volume = Wet Volume × 1.54
Cement / Sand / Ballast calculated from selected concrete class

Base Length (m) *

Base Width (m) *

Base Depth (m) *

Number of Column Bases *

Concrete Class

📊 Column Base Results Mix 1:2:4

📐 Volumes

Single Base Volume

—

m³

Total Wet Volume

—

m³

Dry Volume (×1.54)

—

m³

Concrete Class

—

ratio

🏗 Materials Required

Cement (50 kg bags)
—
bags

Sand
—
tonnes

Ballast / Aggregate
—
tonnes

Wastage Applied

—

% on quantities

Calculation Steps

⚠ Base size, depth and reinforcement must follow structural drawings and soil bearing capacity.

🏗

Foundation Stones

9-inch rubble stone foundation — linear measurement and stone count

Wall Area = Perimeter × Depth
Linear Metres = Wall Area ÷ Stone Thickness (0.20 m)
Linear Feet = Linear Metres × 3.281
Stone Count = (Perimeter × Depth) ÷ (stone L × stone H × thickness) × 1000

House Perimeter (m) *

Foundation Depth (m) *

Stone Thickness (m) default 0.20

Stone Length (mm) default 400

Stone Height (mm) default 200

📊 Foundation Stone Results 9-inch Rubble

📐 Dimensions

Total Wall Area

—

m²

Foundation Courses

—

courses

📏 Linear Measurement

Linear Metres
—
m

Linear Feet
—
ft

Stone Count
—
pieces (inc. wastage)

Wastage Applied

—

%

Calculation Steps

⚠ Stone dimensions assume standard 400×200×200 mm rubble. Adjust inputs for actual stone sizes.

🪨

Backfill Material

Fill volume and tonnage for floor build-up

Volume (m³) = Floor Area × Fill Depth
Tonnes = Volume × Material Density (t/m³)
Murram ≈ 1.8 t/m³ · Hardcore ≈ 1.9 t/m³ · Gravel ≈ 1.65 t/m³ · Selected Fill ≈ 1.75 t/m³

Floor Area (m²) *

Fill Depth (m) *

Material Type

Custom Density (t/m³) if custom

Material Rate (KES/tonne) optional

📊 Backfill Results Murram

Volume

—

m³

Density Used

—

t/m³

Quantity (Tonnes)
—
tonnes (inc. wastage)

Lorry Loads (8t)

—

approx. lorry loads

Calculation Steps

⚠ Lorry capacities vary by vehicle. Confirm with supplier. Compact in 150 mm layers.

🟫

Floor Slab Concrete

Ground bearing slab — Mix Ratio 1:2:4

Wet Volume = Floor Area × Thickness
Dry Volume = Wet Volume × 1.54
Cement Bags = (Dry Vol × 1 / 7) ÷ 0.035 m³/bag
Sand = (Dry Vol × 2 / 7) × 1.6 t/m³
Ballast = (Dry Vol × 4 / 7) × 1.65 t/m³

Floor Area (m²) *

Slab Thickness (m) default 0.15

Concrete Class

📊 Floor Slab Results Mix 1:2:4

📐 Volumes

Wet Volume

—

m³

Dry Volume (×1.54)

—

m³

🏗 Materials Required

Cement (50 kg bags)
—
bags

Sand
—
tonnes

Ballast / Aggregate
—
tonnes

Wastage Applied

—

%

Calculation Steps

⚠ Include BRC mesh per structural engineer. This calc covers concrete only.

🧱

Machine Cut / Ndarugo Stones

Net wall area minus openings — 400 × 200 mm stones

Gross Wall Area = Perimeter × Height
Openings Area = Window Area + Door Area
Net Wall Area = Gross − Openings
Single Stone Area = 0.40 × 0.20 = 0.08 m²
Stone Count = Net Area ÷ 0.08 × (1 + wastage%)

Building Perimeter (m) *

Wall Height (m) *

Total Window Area (m²)

Total Door Area (m²)

Stone Type

Stone Rate (KES/piece) optional

📊 Walling Stone Results Machine Cut

📐 Wall Areas

Gross Wall Area

—

m²

Openings Area

—

m²

Net Wall Area
—
m²

Single Stone Area

—

m²

🧱 Stone Count

Stones (before wastage)

—

pieces

Wastage Stones

—

pieces

Total Stones Required
—
pieces

Wastage Applied

—

%

Calculation Steps

⚠ Mortar and ties calculated separately. Includes perimeter walls only — add internal partition walls if required.

🏠

Roofing Sheets Calculator

Pitched roof area, sheet count, ridge caps — multiple sheet types

Slope Factor = 1 / cos(pitch°)
Roof Area = Floor Area × Slope Factor × 1.1 (overhang)
Effective Cover Width = sheet width − overlap
Sheets (length) = Rafter Length ÷ Effective Sheet Length
Sheets (width) = Roof Width ÷ Effective Cover Width
Total Sheets = Sheets(L) × Sheets(W) × (1 + wastage%)

Floor Area (m²) *

Roof Pitch (degrees) default 25

Building Width (m) for hip/gable

Ridge Length (m) optional

Sheet Type

Sheet Rate (KES/sheet) optional

📊 Roofing Results Box Profile

📐 Roof Geometry

Slope Factor

—

multiplier

Actual Roof Area

—

m² (inc. overhang)

🏠 Sheet Count

Sheets Required
—
sheets (inc. wastage)

Ridge Caps

—

pieces

Eff. Cover Width

—

m per sheet

Sheet Length

—

m standard

Calculation Steps

⚠ Ridge cap count based on 2 m caps at 150 mm overlap. Adjust for hip ridges and valleys. Hip sheets calculated separately.

🟦

Tiles Calculator

Floor or wall tiling estimation with wastage calculation

Total Area = Length × Width
Tile Coverage = Tile Length × Tile Width
Tiles Required = Area ÷ Tile Coverage × (1 + Wastage%)
Boxes Required = Tiles Required ÷ Tiles per Box

Area Length (m) *

Area Width (m) *

Tile Size

Custom Tile Length (m) if custom

Custom Tile Width (m) if custom

Wastage (%) default 10

Tiles per Box optional

Tile Rate (KES/piece) optional

📊 Tiles Results Floor Tiles

📐 Area & Coverage

Total Area

—

m²

Tile Coverage

—

m² per tile

🟦 Quantity Required

Tiles Required
—
pieces (inc. wastage)

Boxes Required

—

boxes

Wastage Applied

—

%

Calculation Steps

⚠ Wastage accounts for cutting, fitting, and future repairs. Add extra 5% for intricate patterns or diagonal layouts.

🎨

Paint Calculator

Wall painting estimation with coats and coverage rate

Total Paintable Area = Wall Length + Wall Width x Height × 2
Or enter area directly = Total Wall Area (m²)
Total Area for Coats = Paintable Area × Number of Coats
Litres Required = Total Area ÷ Coverage Rate (L/m²)
Tins Required = Litres ÷ Tin Size

Calculation Method

Room Length (m) *

Room Width (m) *

Wall Height (m) default 3.0

Window/Door Area (m²) to subtract

Number of Coats default 2

Coverage Rate (m²/L) default 10

Paint Tin Size (L) optional

Paint Rate (KES/litre) optional

📊 Paint Results 2 Coats

📐 Wall Area

Gross Wall Area

—

m²

Openings Deducted

—

m²

Net Paintable Area
—
m²

🎨 Paint Requirements

Total Area (coats)

—

m²

Litres Required
—
L (inc. wastage)

Number of Tins

—

tins

Calculation Steps

⚠ Coverage rates vary by paint type. Emulsion: 10–12 m²/L, Gloss: 8–10 m²/L, Textured: 6–8 m²/L. Add 10% for porous surfaces.

Kenya Construction Cost Calculator

⚠ Important Notes

Material Quantification
Module

Blinding Concrete

Strip Footing Concrete

Column Concrete

Beam Concrete

Column Base Concrete

Foundation Stones

Backfill Material

Floor Slab Concrete

Machine Cut / Ndarugo Stones

Roofing Sheets Calculator

Tiles Calculator

Paint Calculator

Kenya Construction Cost Calculator

⚠ Important Notes

Material QuantificationModule

Blinding Concrete

Strip Footing Concrete

Column Concrete

Beam Concrete

Column Base Concrete

Foundation Stones

Backfill Material

Floor Slab Concrete

Machine Cut / Ndarugo Stones

Roofing Sheets Calculator

Tiles Calculator

Paint Calculator

Material Quantification
Module