# Sense increase in humidity rather than a static value? **URL:** \ **Category:** Questions & Help\ **Tags:** app, z-wave, flow\ **Created:** [January 26, 2021, 9:11am UTC](https://community.homey.app/t/sense-increase-in-humidity-rather-than-a-static-value/41797 "2021-01-26T09:11:50Z")\ **Posts on this page:** 7\ **Page:** 1
**Author:** ![krl69](https://sea1.discourse-cdn.com/flex025/user_avatar/community.homey.app/krl69/32/21560_2.png) [@krl69](https://community.homey.app/u/krl69)\ **Post date:** [January 26, 2021, 9:11am UTC](https://community.homey.app/t/sense-increase-in-humidity-rather-than-a-static-value/41797/1 "2021-01-26T09:11:50Z")
Is it possible to create a logic that detects a rapid rise in humidity? I have a “Aeotek Multisensor 6” which is mounted in the bathroom. I want it to detect that someone is showering or bathing, but the challenge is that the lower humidity value varies. Now it is winter in Norway and we often have low humidity, in summer it is higher. However, it can vary, depending on, among other things, the outdoor temperature. This makes it difficult to set a cut-off value for when you want a flow to be triggered. In addition, the sensor is located 2-3 meters from the bath and shower due to access to electricity, thus it takes a little longer before the humidity increases significantly. Therefore, I prefer it to respond to a rapid increase in humidity instead of just a static value. Is it possible to make a logic via e.g. “Better Logic”? ---
**Author:** ![JPe4619](https://sea1.discourse-cdn.com/flex025/user_avatar/community.homey.app/jpe4619/32/9017_2.png) [@JPe4619](https://community.homey.app/u/JPe4619)\ **Post date:** [January 26, 2021, 11:50am UTC](https://community.homey.app/t/sense-increase-in-humidity-rather-than-a-static-value/41797/2 "2021-01-26T11:50:42Z")
You can place another humidity sensor outside the bathroom, so you can calculate the difference between the ambient humidity and the bathroom humidity. ---
**Author:** ![peltsi51](https://sea1.discourse-cdn.com/flex025/user_avatar/community.homey.app/peltsi51/32/12564_2.png) [@peltsi51](https://community.homey.app/u/peltsi51)\ **Post date:** [January 26, 2021, 3:26pm UTC](https://community.homey.app/t/sense-increase-in-humidity-rather-than-a-static-value/41797/3 "2021-01-26T15:26:18Z")
I have made following logic to control the shower ventilation **Make the ventilation higher if:** - Shower **relative** humidity is over 65% **and** - Shower **absolute** humidity is higher than outdoor **absolute** humidity **and** - Shower **relative** humidity is 13% higher than average indoor **relative** humidity\*\*\*\* **or** - Shower **relative** humidity is over 65% **and** - Average indoor **absolute** humidity is higher than outdoor **absolute** humidity **Make the ventilation lower if:** - Shower **relative** humidity is less than 55% **or** - Outdoor **absolute** humidity is higher than shower **absolute** humidity **or** - Shower **relative** humidity + 10% is higher than average indoor **relative** humidity It works, but maybe, just maybe I have overdone it. 🤣 ---
**Author:** ![Peter\_Kawa](https://sea1.discourse-cdn.com/flex025/user_avatar/community.homey.app/peter_kawa/32/173848_2.png) [@Peter\_Kawa](https://community.homey.app/u/Peter_Kawa)\ **Post date:** [May 11, 2021, 3:29am UTC](https://community.homey.app/t/sense-increase-in-humidity-rather-than-a-static-value/41797/4 "2021-05-11T03:29:50Z")
A bit late, but maybe the app Insight Trends comes in handy. It can detect how fast or how slow a sensors’ value changes over time. ---
**Author:** ![Carl\_William](https://sea1.discourse-cdn.com/flex025/user_avatar/community.homey.app/carl_william/32/56437_2.png) [@Carl\_William](https://community.homey.app/u/Carl_William)\ **Post date:** [July 13, 2022, 8:25pm UTC](https://community.homey.app/t/sense-increase-in-humidity-rather-than-a-static-value/41797/5 "2022-07-13T20:25:39Z")
Hi did you find a good way to control this? ---
**Author:** ![Peter\_Kawa](https://sea1.discourse-cdn.com/flex025/user_avatar/community.homey.app/peter_kawa/32/173848_2.png) [@Peter\_Kawa](https://community.homey.app/u/Peter_Kawa)\ **Post date:** [July 14, 2022, 11:39am UTC](https://community.homey.app/t/sense-increase-in-humidity-rather-than-a-static-value/41797/6 "2022-07-14T11:39:15Z")
Like Jan wrote, you can use an other humidity sensor to compare the values with. I chose to use the same humidity sensor. Flow1 When I enter the bathroom, the current humidity value is saved to a predefined variable. ![Screenshot_20220714-133306_Chrome](https://us1.discourse-cdn.com/flex025/uploads/athom/original/3X/c/0/c0a5f7424d119446763591e778543e78299cc949.jpeg) Flow2 When the hot shower is running, compare the change in humidity, and if it is X % higher than the saved value, fire the action cards. For me, using an increase of 6% works fine. ![Screenshot_20220714-133208_Chrome](https://us1.discourse-cdn.com/flex025/uploads/athom/original/3X/e/f/ef4a072f100cdc4affd6d0e9f2654f1c5bbbf97e.jpeg) ---
**Author:** ![Carl\_William](https://sea1.discourse-cdn.com/flex025/user_avatar/community.homey.app/carl_william/32/56437_2.png) [@Carl\_William](https://community.homey.app/u/Carl_William)\ **Post date:** [July 14, 2022, 7:40pm UTC](https://community.homey.app/t/sense-increase-in-humidity-rather-than-a-static-value/41797/7 "2022-07-14T19:40:46Z")
sounds good i will try it 🙂