🌬️ GSW: Smart Ventilation Suite
Advanced Home Assistant Blueprints by Greece Sky and Weather
Professional-grade blueprints for Home Assistant designed to control ventilation using Absolute Humidity (g/m³) and Dew Point logic.
Created by Iakovos Venieris.
🌡️ Why Absolute Humidity?
Most ventilation automations rely on Relative Humidity (%), which can be misleading.
Relative humidity changes with temperature. This means a system might activate ventilation and accidentally bring more moisture inside the building.
This project solves the problem by using:
• Absolute Humidity (g/m³) • Indoor vs Outdoor comparison • Dew Point condensation protection
This ensures the ventilation fan runs only when it actually removes moisture from the building.
🚀 Blueprints in this Suite 🛁 Advanced Humidity Ventilation (Bathroom)
A smart ventilation automation designed for bathrooms to prevent:
Mold growth
Condensation
Excess humidity
by intelligently comparing indoor and outdoor absolute humidity.
Key Features
✔ Smart Humidity Logic Compares indoor and outdoor absolute humidity to ensure ventilation is only activated when outdoor air is actually drier.
✔ Dew Point Protection Detects potential condensation risk.
✔ Adaptive Runtime Fan runtime automatically adjusts depending on humidity severity:
Condition Runtime High humidity difference 60 minutes Medium humidity difference 30 minutes Condensation risk 30 minutes Low humidity difference 15 minutes
✔ Optional Alarm Integration The automation can run only when the security system is DISARMED.
🧠 Ventilation Logic
The fan activates when either of these conditions is true:
Condition 1 – Humidity Difference
Bathroom Absolute Humidity > Indoor Absolute Humidity + 1 g/m³
AND
Bathroom Absolute Humidity > Outdoor Absolute Humidity + 1 g/m³
Condition 2 – High Moisture Threshold
Bathroom Absolute Humidity ≥ 14.5 g/m³
The fan will automatically stop when humidity drops back to safe levels.
🛠️ Requirements
To use these blueprints you must install the Thermal Comfort Integration via HACS.
It provides the following sensors:
• Absolute Humidity (g/m³) • Dew Point (°C)
Repository:
https://github.com/dizzyit/thermal_comfort
📦 Installation Method 1 – Manual Import
Open the blueprint .yaml file in this repository.
Click Raw.
Copy the URL from your browser.
In Home Assistant go to:
Settings → Automations & Scenes → Blueprints
Click Import Blueprint
Paste the URL.
Although this blueprint includes automatic shutdown logic, it is recommended to create a simple backup safety automation.
Example:
Turn OFF the ventilation fan if it remains ON for more than 2 hours.
This ensures the fan will never run indefinitely in case of:
• sensor failure • communication errors • integration problems
💼 Commercial Licensing & Protection
License: CC BY-NC-ND 4.0
Personal Use
Free for personal use.
Commercial Use
Commercial use is not allowed without written permission.
If you are:
• a professional installer • a smart home company • a system integrator
and wish to use this logic commercially, please contact me.
Redistribution of modified versions is not permitted.
📩 Contact: greekskyweather@gmail.com
☕ Support the Project
If you find this project useful you can support development by buying me a coffee.
Your support helps me dedicate more time to building advanced Home Assistant tools.
📺 YouTube Channel
Follow the project and explore live weather monitoring and sky observations.
Greece Sky and Weather
https://www.youtube.com/@GreeceSkyandWeather
• 24/7 live weather cameras • astronomy timelapses • meteor monitoring • atmospheric phenomena
Monitoring the Greek sky and weather.
© 2026 Iakovos Venieris – Greece Sky and Weather