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Professional calculators, converters and technical resources built to help engineers design, verify and deliver with confidence.
Duct Sizing
Calculate optimal duct dimensions and airflow velocity.
Psychrometrics
Analyse air properties and psychrometric processes.
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Featured Engineering Tools
Practical calculators and converters designed to support faster HVAC and MEP engineering decisions.
Heat Load Calculator
AvailableEstimate sensible and latent cooling loads, total capacity, SHR and recommended AC size.
Open CalculatorHVAC Unit Converter
AvailableConvert common HVAC units for cooling capacity, airflow, pressure, temperature and energy.
Convert UnitsDuct Size Calculator
Coming SoonDetermine round and rectangular duct dimensions from airflow, velocity and friction criteria.
Coming SoonFresh Air Calculator
Coming SoonEstimate outdoor-air requirements using occupancy and floor-area ventilation inputs.
Coming SoonPipe Size Calculator
Coming SoonSize water pipes using design flow, velocity and pressure-drop criteria.
Coming SoonPsychrometric Calculator
Coming SoonAnalyse dry-bulb temperature, humidity, enthalpy and common air-conditioning processes.
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Why Engineers Choose BuildMEP
Practical tools and technical content developed to make everyday engineering work clearer and more efficient.
Accurate Engineering Calculations
Clear inputs, engineering units and visible assumptions help users review how each result is produced.
Built by Engineers
Tools and resources are shaped around practical HVAC, MEP and building-services workflows.
Professional Engineering Guides
Structured technical explanations focus on practical design, selection, installation and troubleshooting.
Product Comparison Tools
Compare relevant technical characteristics to support product evaluation and replacement decisions.
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Popular Engineering Guides
Detailed explanations, comparisons and practical guidance for HVAC and building-services work.
10 Common HVAC Design Mistakes Every Engineer Should Avoid
A practical guide covering cooling loads, equipment sizing, ventilation, ductwork, controls and commissioning.
Read GuideSiemens GCA166.1E vs GCA161.1E: Comparison & Replacement Guide
Compare control signals, feedback, operating functions and practical replacement considerations.
Read ComparisonFCU vs AHU vs FAHU: Key Differences Explained
Understand the role, air source, system arrangement and typical applications of common airside equipment.
Read GuideLatest Engineering Resources
Practical files, templates and technical documents for engineering and project workflows.
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