Nepal Site Engineer Toolkit — Eve Construction

Steel Bar Weight

Bar diameter (mm)

Length per bar (m)

Number of bars

Formula: weight (kg/m) = D² / 162.2 · weight (kg/ft) = D² / 533, where D = diameter in mm

Concrete Materials Estimator

Concrete volume (m³) Nominal mix

Dry volume factor 1.52 · cement 1440 kg/m³ · 1 bag = 50 kg

Brickwork Estimator

Wall length (m)

Wall height (m)

Wall thickness Mortar ratio

≈ 500 modular bricks per m³ of brickwork · mortar ≈ 0.25 m³ per m³

Unit Converter

Land Area Converter

Value

From

To

Hilly: 1 ropani = 16 aana = 64 paisa = 256 daam · Terai: 1 bigha = 20 kattha = 400 dhur

Sut → mm Rebar Converter

Rebar size (sut)

Sut	≈ mm	Standard bar
3 sut	9.5	10 mm
4 sut	12.7	12 mm
5 sut	15.9	16 mm
6 sut	19.1	20 mm
8 sut	25.4	25 mm

1 sut = 1/8 inch ≈ 3.175 mm — the size masons and site workers quote on site

Concrete Estimator — DUDBC

Wet concrete volume (m³) Mix

Dry volume = wet volume × 1.54 · 1 bag cement = 50 kg · Preset norms per DUDBC: M20 ≈ 8 bags/m³, M15 ≈ 6.3 bags/m³

Plaster & Screed Estimator

Area (m²) Plaster

Dry mortar factor 1.33 · Preset norms: 12 mm ≈ 0.11 bags/m², 20 mm ≈ 0.18 bags/m² (1:4 mix, incl. wastage)

Concrete Cube Test Check

Failure load (kN)

Target f_ck (N/mm²)

Test age

Strength = failure load (N) ÷ (150 × 150) mm² — standard 150 mm cube

Lap Length & Seismic Hooks (Fe 500)

Bar diameter (mm)

Tension lap 40d–50d (50d typical on Nepal residential sites) · compression lap min 24d · 135° seismic hook = max(10d, 75 mm) per NBC 105:2020 / IS 13920

Stirrup Spacing & Ductile Detailing

Member type

Effective depth d (mm)

Smallest long. bar dia (mm)

Location	Max stirrup spacing (IS 13920)
Beam — within 2d of joint face (plastic hinge zone)	min(d/4, 8 × smallest long. bar dia, 100 mm)
Beam — elsewhere	d/2
Column — within l_o of joint face	min(smaller dimension/4, 6 × smallest long. bar dia, 100 mm)
Column confinement length l_o	max(larger dimension, clear height/6, 450 mm)

Stirrups need 135° seismic hooks, min max(10d, 75 mm) — see the Lap Length card · column lap splices only in the middle half of the clear height, never inside l_o · NBC 105:2020 adopts equivalent ductile detailing for seismic design

Formwork Stripping Time

Member / prop condition

Member	Stripping time
Walls, columns, vertical faces	16 – 24 hours
Slab soffit (props left under)	3 days
Beam soffit (props left under)	7 days
Removal of props — slab ≤ 4.5 m span	7 days
Removal of props — slab > 4.5 m span	14 days
Removal of props — beam/arch ≤ 6 m span	14 days
Removal of props — beam/arch > 6 m span	21 days

Per IS 456 / NBC — props must remain until concrete gains adequate strength

Gabion Box Material

Gabion box volume (m³)

Standard: 100 × 120 mm double-twisted hexagonal mesh · mesh wire 10 SWG (3.0 mm), selvedge 8 SWG (4.0 mm), lacing 12 SWG (2.4 mm) · lacing wire ≈ 3–5% of mesh weight

Plum Concrete Estimator

Total plum concrete volume (m³)

60% mass concrete (M10/M15) + 40% plum boulders (150–300 mm) — for retaining walls & abutments on hill sites

Road Earthwork Volume

Area A₁ (m²)

Area A₂ (m²)

Mid area A_m (m²)

Length L (m)

End-area: V = L/2 × (A₁ + A₂) · Prismoidal: V = L/6 × (A₁ + 4A_m + A₂) — for cut/fill on hill roads

Pavement Material Sizing

Compacted volume (m³) Layer

DoR norms: GSB compaction factor 1.25–1.30 · WBM/WMM loose:compacted 1.30–1.35 · asphalt density 2.3–2.4 t/m³

Rate Analysis (DUDBC/DoR)

Material cost (Rs) Labour cost (Rs) Equipment cost (Rs)

Unit rate = (material + labour + equipment) × 1.15 · contractor overhead & profit fixed at 15% · VAT 13% on the billable total · use District (Zilla) rates for the municipality

Mortar Factors & Brickwork Norms

Item	Norm
Dry volume factor — concrete	wet volume × 1.54
Dry volume factor — mortar / plaster	wet volume × 1.33 – 1.35
Standard brick (DUDBC)	230 × 115 × 75 mm (9″ × 4.5″ × 3″)
9″ (full) brickwork	530 – 560 bricks per m³ (≈ 15 per cft)
4.5″ (half) brickwork	55 – 60 bricks per m²
1:6 cement-sand mortar, 9″ wall	≈ 1.2 bags cement per m³ of brickwork
1 bag cement	50 kg · 0.0347 m³

DUDBC norms — add 5% wastage on bricks and cement at ordering stage