Indoor humidity chart card

Who it’s for

Facility managers, HVAC engineers, and building managers ask “what is the humidity in this space right now, and has it been drifting outside the comfortable range over the past few hours?” They need both the current reading and the trend to distinguish an HVAC control fluctuation from a persistent comfort problem.

What it does

A sensor reporting humidity = 45% shows the current value color-coded by comfort band alongside a time-series chart of recent readings: orange for Low (0–30%), green for Comfortable (30–60%), and red for High (above 60%). The chart lets facility staff see whether humidity is drifting toward a problem or steadily maintained within range.

• Live humidity reading in % with color coding across three comfort bands
• Historical trend chart shows how relative humidity has evolved over the selected time window
• Shows one sensor’s data per widget; add multiple widgets to monitor different rooms or zones

How to set up

Data keys

Key	Role	Type	Description
humidity	Chart series	Timeseries	Relative humidity in %; change the key name to match your device’s telemetry key
Latest	Latest value	Timeseries	The headline figure above the chart. Its own color ranges are where the band colors are edited
Delta percent	Percentage change	Timeseries	Change against the previous period, as a percentage
Delta absolute	Absolute change	Timeseries	Change against the previous period, in the key’s own unit

The widget ships with a simulated function datasource key labeled Humidity, so it draws random values until you point the datasource at a device and rename the key.

To point it at your own device: open the dashboard in edit mode, open the widget’s Datasources, pick the entity or entity alias, and replace the function key with the key your device reports.

Value ranges

Range (%)	Level	Color
0–30	Low	Orange
30–60	Comfortable	Green
60+	High	Red

How to customize

• To change the time window — adjust the dashboard time filter to show the last hour, day, or week of humidity readings.
• To change the comfort thresholds — edit the color ranges on the Latest data key.
• To change the chart colors — edit the color of each range on the Latest data key.

Tips

• A gradual downward trend from 45% toward 20% over several days in winter indicates the building’s humidification is failing to compensate for cold dry outdoor air entering through the envelope; catching this early prevents occupant complaints and static-discharge events.
• Humidity spikes following rain on a weekend — when the HVAC is in setback mode — may indicate infiltration or building fabric moisture issues that need investigation before the space reopens.
• For green building certification, pair this chart with CO2 and temperature charts to produce a comprehensive indoor environment quality record for the assessment period.