Air Gap Resistance Calculator
The Air Gap Resistance Calculator calculates the thermal resistance of air cavities in building assemblies from gap width, orientation, and ventilation.
Construction
Optimize your construction projects with our powerful calculators. From material estimation to cost analysis and structural calculations, these tools are designed to save time and ensure precision for builders, engineers, and DIY enthusiasts.
Browse our 115 calculators to solve common problems in Construction — from quick estimates to detailed results. This hub links to our most-used tools and guides so you can get answers fast.
Start with the popular picks below, or jump into the full list for more specific use cases.
Hood Fan Size Calculator
The Hood Fan Size Calculator determines the appropriate hood fan extraction rate and duct diameter from hob width, heat output, room volume, and duct length.
Demolition Estimate Calculator
The Demolition Estimate Calculator estimates demolition costs, timelines, and waste disposal from site details, structure type, materials, and regional labour rates.
Bags of Soil Calculator
The Bags of Soil Calculator calculates required bag quantities from project area, depth, and bag size, including an optional wastage allowance.
Board Coverage Calculator
The Board Coverage Calculator calculates how many boards are needed to cover a specified area, factoring board dimensions, overlaps, and wastage.
Cement Lift Pressure Calculator
The Cement Lift Pressure Calculator calculates the pressure required to lift concrete slabs using slab weight, bearing area, friction, and safety factors.
Dock Energy Loss Calculator
The Dock Energy Loss Calculator calculates heat loss and infiltration at loading docks to estimate annual energy costs for warehouses and distribution centres.
Breaker Load Calculator
The Breaker Load Calculator estimates current demand across circuits to select correct breaker ratings and maintain compliance with wiring regulations.
Bags of Mulch Calculator
The Bags of Mulch Calculator calculates required number of mulch bags and projected cost from area, depth, bag size, coverage, and optional waste allowance.
Core Fill Calculator
The Core Fill Calculator calculates the volume of concrete or grout required to core-fill blockwork walls based on dimensions and voids.
Build-Up Rate Calculator
The Build-Up Rate Calculator calculates unit rates by combining labour, materials, plant, waste, productivity, overheads and profit for construction tasks.
Chain-Link Fence Weight Calculator
The Chain-Link Fence Weight Calculator calculates total weight from mesh gauge, height, length, and post spacing, aiding transport and installation planning.
Free Float Calculator
The Free Float Calculator computes the time each activity may be delayed without impacting successor early starts in construction programmes.
Concrete Volume Calculator
The Concrete Volume Calculator calculates the concrete volume needed from entered dimensions and thickness and applies waste allowance and unit preferences.
3-Phase Breaker Calculator
The 3-Phase Breaker Calculator calculates appropriate breaker size and trip rating for three-phase circuits from load, voltage, and power factor.
Concrete Shear Capacity Calculator
The Concrete Shear Capacity Calculator calculates the shear capacity of reinforced concrete members using dimensions, material properties, and relevant design codes.
Influence Line Calculator
The Influence Line Calculator computes influence lines for beams and bridges, helping engineers visualise structural responses under moving loads.
Countersink Diameter Calculator
The Countersink Diameter Calculator calculates the required countersink head diameter from screw size, head angle and desired depth for clean finishes.
Air Exchange Calculator
The Air Exchange Calculator estimates required ventilation rates and air changes per hour from space volume and system airflow.
Deck Height Calculator
The Deck Height Calculator calculates finished deck level and post lengths from joist depth, beam height, and existing ground level.