Skip to content
h2x Design Software
  • Product
        • Features

        • Exports

        • HVAC
        • Hydronic / Heating
        • Domestic Water
        • Duct / Ventilation
        • Heat Load
        • Heat Loss
        • Chilled Water
        • Fire Protection
        • MVHR
        • Stormwater
        • Gas
        • Wastewater
        • 3D View
        • PDF Drawing Set
        • Bill of Materials / MTO
        • Heat Load Report
        • System Sizing Report
        • AutoCAD Integration
        • Revit Integration
        • Design Share
  • Solutions
        • Consultants
        • Contractors / Installers / Trades
        • Manufacturers
  • Resources
        • Learn

        • Support

        • Discover

        • Heat Pumps eBook
        • Legionella eBook
        • MVHR eBook
        • Training Webinars
        • Uni
        • User Guide
        • Customers
        • Calculators
        • Use Cases
        • Blog
        • Security
        • Knowledge
        • Partnerships
        • About

Contact   |   Login

Watch Demo
h2x Design Software
Demo

  • Product
        • Features

        • Exports

        • HVAC
        • Hydronic / Heating
        • Domestic Water
        • Duct / Ventilation
        • Heat Load
        • Heat Loss
        • Chilled Water
        • Fire Protection
        • MVHR
        • Stormwater
        • Gas
        • Wastewater
        • 3D View
        • PDF Drawing Set
        • Bill of Materials / MTO
        • Heat Load Report
        • System Sizing Report
        • AutoCAD Integration
        • Revit Integration
        • Design Share
  • Solutions
        • Consultants
        • Contractors / Installers / Trades
        • Manufacturers
  • Resources
        • Learn

        • Support

        • Discover

        • Heat Pumps eBook
        • Legionella eBook
        • MVHR eBook
        • Training Webinars
        • Uni
        • User Guide
        • Customers
        • Calculators
        • Use Cases
        • Blog
        • Security
        • Knowledge
        • Partnerships
        • About

Posts by Jonathan Mousdell

Plumbing Fixture Units, Explained: Charts for Every Code

By Jonathan Mousdell | September 3, 2026 | 0
Plumbing Fixture Units, Explained: Charts for Every Code

Supply, Drainage, and a Chart for Every Major Code

Read More

What Is Thermal Lag? Understanding Time Lag and Thermal Mass in HVAC Design

By Jonathan Mousdell | August 27, 2026 | 0
What Is Thermal Lag? Understanding Time Lag and Thermal Mass in HVAC Design

Why heat arrives hours after the temperature peaks, and what that means for cooling loads, plant sizing, and comfort.

Read More

ASHRAE 183: The Industry Standard for HVAC Load Calculations

By Jonathan Mousdell | July 13, 2026 | 0
ASHRAE 183 HVAC load calculations graphic showing heating and cooling loads, weather data, and compliance reporting for a commercial building

Learn what ASHRAE Standard 183 requires for HVAC load calculations and what engineering design software needs to produce compliant, audit-ready results.

Read More

How to Calculate Air Changes Per Hour

By Jonathan Mousdell | July 8, 2026 | 0
How to Calculate Air Changes Per Hour

Learn the ACH formula, how to calculate air changes per hour from airflow and room volume, and typical values by room type.

Read More

CFM Calculation Formula: 4 Ways to Calculate Required Airflow

By Jonathan Mousdell | June 29, 2026 | 0
Blueprint-style duct design showing four ways to calculate CFM

Four CFM calculation formulas for ventilation, cooling load, and duct sizing, with a fully worked example.

Read More
Older Posts »
h2x Design Software
Awards & Recognition
h2x Software Best Customer Support 2026
HVAC Plumbing BIM BOM
h2x Capterra Best Value 2026
HVAC Plumbing BIM PDF
h2x Software Most Recommended 2026
BIM
Ratings & Certifications
h2x Capterra Reviews
h2x Software Advice Reviews
h2x GetApp Reviews
h2x Google Reviews
h2x ISO 270012022 Certification
h2x Cibse Verified

Subscribe to our monthly newsletter

Features

HVAC Design

Hydronic / Heating Design

Domestic Water Design

Duct Design

Heat Load Calculations

Heat Loss Calculations

Fire Protection Design

Chilled Water Design

MVHR Design

Gas Design

Stormwater Design

Wastewater Design

3D View

Solutions

Consultants

Contractors / Installers / Trades

Manufacturers

Exports

PDF Drawing Set

Bill Of Materials (Material Takeoff)

AutoCAD Integration

Revit Integration

System Sizing Report

Heat Load Report

Design Share

Resources

Contact

About

Customers

Use Cases

Training Webinars

Learn Uni

User Guide

Online Calculators

Comparisons

Access Management

App Status

Knowledge Hub

Latest Blog Posts

What is Thermal Lag? Time Lag and Thermal Mass in HVAC Design

Best MEP Software in 2026: 10 Tools Compared

How to Calculate Air Changes Per Hour

See h2x in action, or book a quick call with our team.

Request a Demo

Follow Us

h2x X aka Twitter h2x Facebook h2x Instagram h2x Linkedin h2x YouTube h2x TikTok

© 2026 - H2X Ltd. | Privacy Policy