Construction Engineering Tools
Accurate volume, reinforcement, quantity takeoff, and site estimation calculators built for civil contractors, structural engineers, and site managers.
Construction Engineering Workspace
From engineering calculations and measured quantities to BOQ, cost estimation, project deliverables and handover — in one connected construction workspace. Create one project, define the building, work the 21-stage lifecycle, and keep every quantity traceable back to the calculation that produced it.
- Project
- Components
- Quantities
- BOQ
- Rate & Cost
- Procurement
- Handover
Reference building — 30 floors, 3 basements
A worked demonstration driven by the real calculation engines and the real quantity pipeline: quantities consolidate, a bill of quantities is generated, and rates produce a cost summary through the same rules a real project uses. Its dimensions are illustrative inputs, not a structural design, and its rates are marked assumed — they are not market prices or supplier quotations.
Open the Reference Development Project →Engineering Workflows
Concrete Engineering Workflow
From structure inputs to material quantities and site documentation.
- Project Input Element type and dimensions
- 1 Volume Concrete quantity in place
- 2 Mix / Quantity Mix proportions and materials
- 3 Rebar Reinforcement weight per meter
- 4 Material Quantities Takeoff and ordering quantities
- Site Documentation Site-ready sheet for the crew
Featured Tools
Concrete Volume Calculator
Build a multi-item concrete quantity schedule for slabs, footings, beams, walls and columns, with category subtotals and an Excel export.
Per item: V = L x W x H (slab, beam, wall, curb) | L x W x D (footings) | A x H (columns) | (PI/4) D^2 x H (circular). Totals: net = SUM(items); supply = net + wastage%. Concrete Mix Design Calculator
Compute per-batch and per-cubic-meter quantities of cement, sand, aggregate, and water from a mix ratio.
V_dry = V × 1.54 · M_mat = V_dry × (ratio / Σ ratios) · Water = w/c × cement mass Rebar Weight Calculator
Compute theoretical rebar steel weight per meter and total tonnage from bar diameter and lengths.
W = d² / 162 (kg/m, d in mm) Construction Disciplines
Concrete Engineering
Volume, slab, footing, column, and mix design calculators.
Explore tools →Rebar & Reinforcement
Weight per meter, bar quantities, length, and reinforcement spacing.
Explore tools →Masonry & Blockwork
Block quantity, mortar volume, and wall estimation.
Explore tools →Earthwork & Excavation
Trenching, cut & fill volumes, and backfill estimations.
Explore tools →Stormwater & Drainage
Stormwater runoff estimation, drainage design, and rational method calculations.
Explore tools →Cost & Quantity Estimation
Material cost, quantity takeoff, and bill of quantities (BOQ).
Explore tools →Site Management Tools
Productivity, equipment cycles, and site operational calculations.
Explore tools →Sustainability & Carbon
Embodied carbon screening and low-carbon design comparisons.
Explore tools →Electrical Power & Distribution
Voltage drop, conductor sizing, conduit fill, power factor and transformer capacity.
Explore tools →Heating, Ventilation & Air Conditioning
Cooling loads, sensible and latent split, tonnage, airflow and duct sizing.
Explore tools →Structural Steel
Beam capacity and deflection, column buckling, section properties and retaining walls.
Explore tools →Geotechnical Engineering
Bearing capacity, pile capacity, settlement, soil phase relationships and earth pressure.
Explore tools →Civil Drainage & Highways
Culvert and storm drain capacity, detention storage, asphalt quantities and curve geometry.
Explore tools →Mechanical Fluids & Heat Transfer
NPSH, fitting losses, LMTD, pipe thermal expansion and weir discharge.
Explore tools →Solar & Off-Grid Energy
Load audits, array sizing, battery banks, inverters and charge controllers.
Explore tools →MEP Coordination
Combined mechanical, electrical and plumbing load coordination for whole buildings.
Explore tools →MEP Electrical
Electrical supply, lighting distribution and containment across a building.
Explore tools →MEP Plumbing
Water supply, hot water and sanitary provision across a building.
Explore tools →Fire & Life Safety
Fire load, egress, detection and alarm coordination.
Explore tools →Fire Water & Egress
Fire water demand, pump sets and escape provision.
Explore tools →Finishes & Facades
Finishes quantities, facade performance and external finishes.
Explore tools →Site Infrastructure & External Works
External works, service runs, hardstanding and site coordination.
Explore tools →Testing & Commissioning
Systems testing, commissioning activities and handover records.
Explore tools →Basement & Substructure
Basement works, retaining structures and below-ground construction.
Explore tools →Metalwork & Joinery
Doors, windows, handrails, balustrades and metal frames: quantity schedules and measurable metalwork.
Explore tools →Vertical Transportation
Lifts, escalators and vertical circulation capacity.
Explore tools →Envelope, Facade & Roofing
Facade, glazing and roofing performance and quantities.
Explore tools →Specialized tools at a glance
Each visual shows exactly what its calculator computes. Select any tool to open it.
Each visual shows exactly what its calculator computes. Select any tool to open it.
Concrete Volume Calculator
Build a multi-item concrete quantity schedule for slabs, footings, beams, walls and columns, with category subtotals and an Excel export.
Open tool →Rebar Weight Calculator
Compute theoretical rebar steel weight per meter and total tonnage from bar diameter and lengths.
Open tool →Masonry & Block Quantity Calculator
Estimate block quantities, mortar volume, and wall material takeoff from wall geometry and joint thickness.
Open tool →Earthwork Cut and Fill Calculator
Estimate site earth movement balance and bulk haulage volumes with swell and shrinkage factors.
Open tool →Steel Weight Calculator
Compute structural steel and reinforcement weight for plates, bars, pipes, and standard sections using steel density.
Open tool →Concrete Mix Design Calculator
Compute per-batch and per-cubic-meter quantities of cement, sand, aggregate, and water from a mix ratio.
Open tool →Guides and engineering resources
All Construction Engineering Tools
91 ToolsConcrete Volume Calculator
Build a multi-item concrete quantity schedule for slabs, footings, beams, walls and columns, with category subtotals and an Excel export.
Per item: V = L x W x H (slab, beam, wall, curb) | L x W x D (footings) | A x H (columns) | (PI/4) D^2 x H (circular). Totals: net = SUM(items); supply = net + wastage%. Slab Concrete Volume Calculator
Calculate concrete volume for rectangular and L-shaped slabs with slab count and wastage margins.
V = A_plan × H · V_total = V × n · V_ready = V_total × (1 + wastage/100) · Bags = ceil(V_ready / 0.033) Footing & Foundation Volume Calculator
Calculate concrete required for spread (pad) footings and strip footings, per-footing and total volumes with ready-mix allowance.
V = L × W × D × n · V_ready = V_total × (1 + wastage/100) Column Concrete Volume Calculator
Accurate concrete requirements for round, square, and rectangular structural columns.
V = A × H × n · A = (π/4)d² round, b×b square, w×d rectangular Concrete Mix Design Calculator
Compute per-batch and per-cubic-meter quantities of cement, sand, aggregate, and water from a mix ratio.
V_dry = V × 1.54 · M_mat = V_dry × (ratio / Σ ratios) · Water = w/c × cement mass Rebar Weight Calculator
Compute theoretical rebar steel weight per meter and total tonnage from bar diameter and lengths.
W = d² / 162 (kg/m, d in mm) Rebar Quantity Takeoff Calculator
Estimate number of reinforcement bars required for slabs and walls based on spacing and cover.
Bars = ⌊(L - 2c) / s⌋ + 1 Masonry & Block Quantity Calculator
Estimate block quantities, mortar volume, and wall material takeoff from wall geometry and joint thickness.
N = ceil(L/courseW) × ceil(H/courseH) · Mortar = V_bed + V_perp Steel Weight Calculator
Compute structural steel and reinforcement weight for plates, bars, pipes, and standard sections using steel density.
W = V × ρ_steel (ρ ≈ 7,850 kg/m³) Construction Material Quantity Takeoff Calculator
Quantity takeoff for bulk construction materials with wastage: aggregate, sand, cement, and general volume-mass conversions.
Q = V × (1 + wastage/100) · m = Q × ρ Construction Cost Escalation & Scenario Calculator
Escalate a base construction cost to a target date with a user-supplied annual rate and compare alternative escalation scenarios.
C(t) = C₀ × (1 + r/100)^n · n = days ÷ 365.25 Embodied Carbon Screening & Comparison Calculator
Compare two design options on screened embodied carbon using user-supplied emission factors, with breakdown and per-m² intensity.
kgCO₂e = Σ (material quantity × user factor) · intensity = kgCO₂e / area Stormwater Runoff (Rational Method) Calculator
Estimate peak stormwater runoff with the Rational Method (Q = C·i·A) for drainage design and storm sewer sizing.
Q = 2.78 × C × i × A (L/s, A in ha, i in mm/h) Trench Excavation & Bedding Calculator
Calculate trench excavation volume, pipe displacement, bedding material quantity, and backfill volumes.
V_trench = A × L · Backfill = V_trench − V_pipe − V_bedding Earthwork Cut and Fill Calculator
Estimate site earth movement balance and bulk haulage volumes with swell and shrinkage factors.
Net = ΣCut − ΣFill (bank m³) · Export = Net × (1 + swell/100) · Import = −Net × (1 + shrink/100) MEP Electrical Load & Distribution Calculator
Screening-level electrical load and distribution takeoff: connected load, max demand, main cable length, distribution boards, MCBs.
Connected Load = Area × W/m² · Max Demand = Connected × Diversity · DBs = 2 × Floors · MCBs = 3 × Units MEP Plumbing & Water Supply Calculator
Screening-level plumbing takeoff: fixture units, water tank count, cold/hot water pipe length, drainage pipe length.
FU = Units × FU/unit · Tank = ceil(Units × FU/unit × 0.8 / 1000) · Pipe = Floors × Run per floor MEP Mechanical (HVAC) Calculator
Screening-level HVAC takeoff: air volume, cooling load, AHU count, duct length, diffuser count.
Air Volume = Area × Height × ACH · Cooling = Area × W/m² · AHUs = Floors · Duct = Area × Ratio · Diffusers = Units × per Unit Fire & Life Safety Calculator
Screening-level fire protection takeoff: sprinkler heads, riser length, hydrant count, extinguisher count, alarm device count.
Heads = Area / Coverage · Riser = Floors × 3.2 · Hydrants = Perimeter / Spacing · Extinguishers = 2 × Floors · Alarms = 2 × Units Finishes & Facades Calculator
Screening-level finishes takeoff: plaster volume, paint area, tile area, glazing area, flooring area.
Plaster = Wall Area × Thickness · Paint = Wall Area · Tiles = Sellable × Ratio · Glazing = Sellable × Ratio · Flooring = Sellable Site Infrastructure & External Works Calculator
Screening-level external works takeoff: paving area, drainage length, landscaping area, fencing length, street light count.
Landscaping = Site × Ratio · Paving = Site − Footprint − Landscaping · Drainage = Site × Ratio · Fencing = 4 × √Site · Lights = Fencing / Spacing Testing & Commissioning Calculator
Screening-level testing & commissioning takeoff: test points, commissioning days, instruments.
Test Points = Systems × Points/System · Commissioning Days = Systems × Days/System · Instruments = Systems × Instruments/System Structural Framing Calculator
Screening-level RC framing takeoff: beams, core/shear walls, stair flights, and wall/soffit formwork derived from level count and floor plate.
Beams = Lines/Floor × Length × Levels × Section; Core = Plan Area × Thickness × Levels; Stairs = Risers × Going × Width × Flights; Formwork = Vertical Faces + Soffit Area Basement Works Calculator
Basement structure takeoff: base slab, retaining walls, basement columns, grade beams, ramp decks, tanking, sumps and reinforcement — from the building footprint and perimeter.
Base Slab = Footprint × Thickness × Levels; Retaining Walls = Perimeter × Depth × Thickness × Levels; Waterproofing = Slab + Wall Faces; Rebar = Concrete × kg/m³ Vertical Transportation Calculator
Screening-level lift group sizing from unit population and levels served, with the derived lift shaft construction area.
Population = Units × Persons/Unit × Factor; Cars = Peak Population ÷ (Car Capacity × Rounds per Interval); Shaft Area = Shaft Perimeter × Height × Lifts Envelope, Facade & Roofing Calculator
Geometric facade takeoff from the building perimeter and storey count: glazed area, opaque panels, parapet and roof membrane — not a share of sellable area.
Facade = Perimeter × Storeys; Glazed = Facade × Glazing %; Opaque = Facade × Panel %; Roof = Footprint × Coverage % Electrical Supply & Lighting Calculator
Sizes the transformer and standby generator from a computed maximum demand, plus main switchboards and general/emergency luminaire counts.
Transformer = Max Demand × (1 + Allowance) rounded up to a standard rating; Generator = Max Demand × Critical Share; Luminaires = Lit Area ÷ Area per Luminaire Plumbing Demand & Stormwater Calculator
Demand-based water sizing: storage volume from per-capita demand, booster pump set, hot water demand, and external stormwater flow and outfall size.
Storage = Population × Demand × Drawdown Hours (floored at a minimum); Stormwater = Contributing Area × Rainfall Intensity; Outfall rounded up to a standard diameter Fire Water & Egress Calculator
Occupant load, fire water storage from flow × duration (floored at a minimum), duty/standby pump sets, escape stair count and rated fire doors.
Occupant Load = Total GFA ÷ Occupant Density; Tank = Flow × Duration (floored at minimum); Pumps = Zones × 2; Doors = Stairs × Levels Served Voltage Drop Calculator
Calculate conductor voltage drop and the voltage actually delivered to the load for single-phase, three-phase and DC circuits.
dV = k x I x R x L, with k = 2 for DC/single-phase and 1.732 for three-phase Wire Sizing Calculator
Size an electrical conductor from both its ampacity and its voltage drop over the run, and see which of the two governs.
R_max = (p/100) x V x 1000 / (k x I x L); the smallest standard size with R <= R_max and ampacity >= I is selected Conduit Fill Calculator
Check electrical conduit fill against the permitted percentage and find the smallest standard conduit that accepts the conductors.
fill% = (n x A_conductor) / A_conduit x 100, limited to 53% / 31% / 40% for 1 / 2 / 3 or more conductors Power Factor Correction Calculator
Calculate the reactive power in kVAr that must be removed with capacitors to reach a target power factor.
Qc = P x (tan acos(pf1) - tan acos(pf2)) Transformer Sizing Calculator
Select the next standard transformer rating from connected load, demand factor and a future growth allowance.
S_standard >= S_connected x demand factor x (1 + growth) Sensible & Latent Heat Calculator
Split an airflow and its temperature and humidity differences into sensible and latent cooling loads.
Qs = 1.08 x CFM x dT ; Ql = 0.68 x CFM x dW (grains/lb) Refrigerant Charge Calculator
Refrigerant charge mass against circuit volume, with superheat and subcooling checked against the bands you supply to flag a floodback or flashing condition.
m = V·ρ; SH = T_suction − T_sat(evap); SC = T_sat(cond) − T_liquid Cooling Tonnage & Airflow Calculator
Convert a cooling load in Btu/h to tons of cooling and to the matching airflow in CFM.
tons = Btu/h / 12,000 ; CFM = tons x cfm per ton Duct Sizing Calculator
Size round and rectangular ducts from airflow and a design velocity, returning the next standard size and the actual velocity.
A = Q / v ; D = sqrt(4A/pi) Cooling Load Calculator
First-pass cooling load from envelope U-values, areas and internal gains, converted to tons and airflow.
Q = sum(U_i x A_i x dT) + 3.412 x internal watts Fan Total Static Pressure Calculator
Total fan static pressure from a schedule of duct, fitting and terminal losses, with the margin against the static you have available and the item carrying most of it.
TSP = sum duct friction + sum fitting losses + sum terminal / plant losses Fan System Curve Calculator
Plot the duct system resistance curve from your design point and see what extra airflow costs, plus what data is still needed for a fan operating point.
dP(Q) = dP_d * (Q / Q_d)^2 Duct Friction & Pressure Drop Calculator
Calculate round duct velocity, Reynolds number, friction factor and pressure drop per 100 ft before selecting a fan.
f = 0.25 / [log10(e/3.7D + 5.74/Re^0.9)]^2 ; dP = f (L/D) rho V^2 / 2 Steel Beam Capacity Calculator
Allowable bending and deflection check for a simply supported steel beam, reporting which criterion governs.
M = wL^2/8 or PL/4 ; Mn = 0.66 x Fy x Sx ; governing load = min(bending, L/240 deflection) Beam Deflection Calculator
Elastic beam deflection for six support and loading arrangements, compared with the L/240 serviceability limit.
delta = k x w L^4 / EI or k x P L^3 / EI, with the limit taken as L/240 Falsework Load Calculator
Falsework load path from slab self-weight and imposed construction load down through the bearer, props and sole boards, checking each step against a capacity you supply.
W = A·h·ρ·g; F_prop = (W·factor + W_imposed) / n Column Buckling Calculator
Euler and Johnson critical loads for a slender column, with the slenderness ratio and the governing formula reported.
Pcr = pi^2 E I / (K L)^2 ; Pjohnson = A (Fy - Fy^2 lambda^2 / 4 pi^2 E) Section Properties Calculator
Area, second moments of area, radii of gyration and section moduli for rectangles, boxes, pipes, I-sections and channels.
I = integral y^2 dA ; r = sqrt(I/A) ; S = I / c Retaining Wall Stability Calculator
Check overturning, sliding and bearing of a retaining wall from Rankine active earth pressure.
Ka = (1 - sin phi)/(1 + sin phi) ; FSo = W B/2 / sum(Pa y) ; FSs = (W tan(2phi/3) + cB) / Pa Anchor Pull-out Capacity Calculator
Check a mechanical anchor against both failure modes — concrete cone breakout and steel tension — and see which one actually limits it.
N_concrete = c * pi * d * L * k | N_design = min(N_concrete, N_steel) Roof Snow Load Calculator
Roof snow load from the ground value and the shape, exposure and thermal coefficients, with the extra force from drifting at an upstand.
p_k = mu * C_e * C_t * s_k Wind Load Calculator
Velocity pressure from the site, then the surface pressure and total force for a shape coefficient you supply for the surface in question.
q_p = 0.5*rho*v^2*c_e ; p = q_p*c_pe ; F = p*A*C_f Seismic Base Shear Calculator
Design base shear as the seismic weight times the response coefficient, with the ductility the structure is allowed to absorb shown alongside.
V = C_s * W Slope Stability Calculator
Ordinary (Fellenius) factor of safety over a circular slip surface built from slices you define, with pore pressure applied to each slice.
FoS = sum(c*L + N*tan(phi)) / sum(W*sin(alpha)) Soil Bearing Capacity Calculator
Terzaghi bearing capacity with the standard shape factors, divided by a global safety factor to give an allowable pressure.
qu = c Nc sc + q Nq + 0.5 gamma B Ng sgamma ; q_all = qu / FS Pile Capacity Calculator
Single pile capacity in clay or sand from skin friction and end bearing, split into components and divided by a safety factor.
Qs = alpha c pi D L ; Qp = Nc c pi D^2 / 4 ; Q_all = (Qs + Qp)/FS Foundation Settlement Calculator
Estimate immediate elastic settlement and one-dimensional consolidation settlement beneath a footing.
de = q B (1 - nu^2) If / E ; sc = Cc H /(1+e0) log10((s0 + ds)/s0) Soil Voids Ratio Calculator
Derive void ratio, porosity, degree of saturation and the dry, saturated and submerged unit weights from bulk unit weight and water content.
e = (Gs gamma_w (1+w) / gamma) - 1 ; n = e/(1+e) ; Sr = w Gs / e Differential Settlement Calculator
Angular distortion and differential settlement along a row of footings, from your reference settlement and bearing pressures, finding the worst local pair rather than the end-to-end average.
s = (σ/σ_ref)·s_ref; Δ/L = |s_j − s_i| / L (local pairs) Earth Pressure Calculator
Rankine active and at-rest horizontal earth pressure with surcharge, resultant thrust and the height at which it acts.
Ka = (1-sin phi)/(1+sin phi) ; K0 = 1 - sin phi ; Pa = 0.5 gamma H^2 Ka + q Ka H Culvert Capacity Calculator
Full-flow culvert capacity and velocity from the Manning equation, or the smallest barrel that passes a design flow.
Q = (1/n) A R^(2/3) S^(1/2) with R = D/4 for a full circular barrel Culvert Scour Calculator
Local scour hole depth at a culvert inlet from the HEC-18 inlet shear relation, with the live-bed alternative reported separately rather than added to it.
u* = C_d·v·√g; τ_c = θ_c·ρ_w·(s−1)·g·D50; y_s = 0.325·(y_t·D50/τ_c) Storm Drain Sizing Calculator
Select the smallest standard storm drain pipe that passes the design flow and check the self-cleansing velocity.
Q = (1/n) A R^(2/3) S^(1/2) with a minimum velocity check of about 0.75 m/s Detention Basin Calculator
Detention storage volume and pond footprint from the peak inflow, the permitted discharge and the design storm.
Q = 2.78 C i A ; V = (Qin - Qout) t Asphalt Quantity Calculator
Convert plan area and layer thickness into asphalt volume, tonnage and the number of tipper deliveries needed.
V = A x t ; m = V x density x (1 + waste) Pavement Layer Calculator
Required flexible pavement thickness from wheel load and section modulus, split into wearing course, base and sub-base by the equivalency factors you supply.
ε_z = 1.5·q_v/E_p · 1/√(1+(h/a)²); h = a·√(k²−1) Horizontal Curve Calculator
Circular curve geometry from the deflection angle and radius, with a speed check from superelevation and side friction.
T = R tan(d/2) ; E = R(sec(d/2) - 1) ; M = R(1 - cos(d/2)) ; V = sqrt(gR(e+f)) Condensate Line Calculator
Condensate drain line sizing including the flash steam released as hot condensate drops to atmospheric, checked against the gravity capacity of the line at the slope you enter.
f_flash = h_fg/(h_fg + c_p·ΔT); load = m·(1−f_flash)·(1+S) Compressed Air Receiver Sizing Calculator
Size an air receiver and find how much free air it releases over the pressure swing, the run time it gives the network, and the volume a required run time needs.
V_free = V x (P1_abs - P2_abs) / P_atm Water Hammer Surge Calculator
Surge pressure from a valve closure or pump trip, with the rapid-closure (Joukowsky) and slow-closure regimes separated by the pressure-wave round trip.
dP = rho*a*dV (t <= 2L/a) | 2*rho*L*dV/t (t > 2L/a) Expansion & Pressurisation Vessel Sizing Calculator
Size the vessel that absorbs a closed water loop’s thermal expansion, with the usable pressure fraction and the pre-charge the sizing depends on.
V_t = (beta * dT * V_s) / (1 - P1/P2) Sprinkler Branch Hydraulic Calculator
Pressure balance along a sprinkler branch from Hazen-Williams friction loss, with the residual at the riser end and at the most remote head checked against the band you enter.
h_f = 10.67·L·Q^1.852/(C^1.852·d^4.87); Q = K·√P NPSH Calculator
Net positive suction head available at the pump from pressure, vapour pressure, static head and suction friction.
NPSH(A) = (Pa - Pv)/(rho g) + Hs - Hf Pipe Fitting Loss Calculator
Head loss, pressure drop and equivalent length for a pipe fitting from its K-value and flow velocity.
hL = K V^2/(2g) ; Le = K D / f LMTD Calculator
Log mean temperature difference for a counter-flow heat exchanger and the heat transfer area it implies.
dTlm = (dT1 - dT2)/ln(dT1/dT2) ; A = Q/(U F dTlm) Pipe Thermal Expansion Calculator
Free linear expansion of a pipe run for a given material, length and temperature rise, in millimetres and per 100 m.
dL = alpha x L x dT Weir Flow Calculator
Discharge over rectangular, contracted, V-notch and Cipolletti weirs from the head above the crest.
Q = 1.84 L H^1.5 (rectangular) ; Q = 1.38 H^2.5 (90 degree V-notch) Energy Load Audit Calculator
Convert appliance watts and daily running hours into a daily energy demand in watt-hours and kilowatt-hours.
E_day = sum(W_i x h_i) Solar Array Sizing Calculator
Number of photovoltaic modules needed for a daily energy demand from peak sun hours and a system derating factor.
P_array = E_day / (PSH x (1 - derate)) ; n = ceil(P_array / P_module) Battery Bank Sizing Calculator
Storage energy and ampere-hours for a daily demand, autonomy period and depth of discharge, with the series and parallel layout.
E_bank = E_day x days / DoD ; Ah = E_bank / V Inverter Sizing Calculator
Continuous and surge inverter rating from the largest load, a load-type surge factor and a design margin.
P_cont = P_load x (1 + margin) ; P_surge = P_load x surge factor Solar Thermal Collector Area Calculator
Size a flat-plate solar thermal collector from a heat balance — once for the daily hot water demand and once for the peak hour — and see which one actually governs.
q_u = eta0*G - U_L*(Tabs - Tf) | A = max(daily energy sizing, peak hour sizing) Crane Lift Calculator
Static sling leg tension for a bridle lift, with the 1/cos(b) angle rise kept separate from the per-leg share and the rigging efficiency applied for 3 legs or more only.
T_leg = W / (n · cos β); efficiency divided in for n ≥ 3 Charge Controller Sizing Calculator
Charge controller current rating from array watts and battery voltage, with MPPT or PWM correction and 25 % headroom.
I = P_array / V_battery ; I_controller = I x 1.25 Concrete Formwork Pressure Calculator
Lateral formwork pressure for a concrete pour from placement rate, temperature and unit weight, capped at the hydrostatic head.
p = Cw Cc (7.2 + 785 R/(T + 17.8)), capped at the fresh lift hydrostatic head Concrete Block Wall Calculator
Block count and bedding mortar quantity for a block wall, with an opening deduction and a waste allowance.
N = A_net x 12.5 blocks/m2 ; mortar = A_net x 0.028 m3/m2 Rebar Development & Splice Calculator
Tension development length and Class A and B lap splices for a bar diameter, steel grade and concrete strength.
ld = (fy x psi_t x psi_e x psi_s) / (2.1 x lambda x sqrt(fc)) x db Staircase Concrete Volume Calculator
Concrete volume of a reinforced concrete staircase, split into waist slab, steps and landing.
L = sqrt((n g)^2 + (n r)^2) ; V = L t w + n (0.5 r g w) Chloride Ingress & Cover Durability Calculator
Fickian chloride diffusion to the reinforcement, reporting the time to corrosion at your cover and the cover needed for the design life.
C(x,t) = Cs * erfc(x / (2*sqrt(D*t))) Plaster & Screed Volume Calculator
Plaster volume, dry mix volume, cement bags and sand quantity for a given area, thickness and mix ratio.
V_wet = A t ; V_dry = 1.33 V_wet ; cement = V_dry x kg per m3 of the chosen mix Waterproofing Takeoff Calculator
Measured-area takeoff for waterproofable surfaces, with declared layer counts. Material quantity stays unresolved until a product coverage rate is supplied.
A = L x W per surface ; area to treat = total measured area x declared layers ; units = area / user-entered coverage Joinery & Metalwork Schedule Calculator
Count and dimension schedule for doors, windows, handrails, balustrades and metal frames. Quantity takeoff only, not a manufacturing specification.
Count ; area = count x width x height ; balustrade area = run length x height ; frame length = count x frame length Knowledge & Resources
Technical Guides
Concrete, rebar, and construction practice references.
Explore →Engineering Concepts
Materials, reinforcement, and structural concepts.
Explore →Equipment References
Construction equipment and machinery.
Explore →Manufacturers
Engineering component manufacturers.
Explore →Engineering Projects
Real-world construction and infrastructure projects.
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