Bathroom scenario (twin circuits?)

Hi, I’m extending and refurbishing our home and wanted to use ‘smart’ things to improve the way we use the spaces.

I have an idea for a lighting solution for the bathrooms however I’m not sure of the best way to do it or the components I would need. I will also have a neutral available at the light switch if that makes a difference.

For the bathroom at night I would like a single light to go on with an amber/red colour and dimmed. I also want the option to turn on the full lights if required. During the day all the lights would come on.

I thought I could possibly do it like this:

Have two lighting circuits in the bathroom - one with a single light and the other with the remaining lights (including the extractor fan). A double smart switch where if button 1 was pressed the circuit with the single light would come on with a smart bulb (that would also change colour and dim). If button two was pressed then circuit two would come on with lights and the fan and it would also trigger the single smart bulb to come on at full brightness and white colour.

Would this work and is there any better ways to achieve this. I prefer not to have all the bulbs as smart bulbs and prefer circuit two (the one with the fan) to just be regular bulbs. I apricate that in my solution above the system is not intelligently reacting to night and day and it is driven by a human decision on what button to press – I’m ok with this, just need it to be simple.

At the moment I prefer control via switches however I may also consider adding a motion detectors into the set-up later.

I hope all the above provides the information needed and that someone may be able to help. Many thanks.

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Welcome to SmartThings!

First question…where are you located? Depending on your region, there will be different solutions available based on the products available as well as local building requirements.

First, the question of Color…you’re not going to find wall-switches/controllers that will be able to give you color control. That is exclusively the realm of smart bulbs. So, if you want color, you’re going to have to go that route.

Is it important to you that the fan and lights be controlled separately or do you want to maintain control of the fan/lights together?

If the later, you are going to have to go with a smart switch that is rated for fan control. You won’t be able to go with a dimmer because that won’t interact well with your extractor fan. So, you’ll only be able to choose between full on or off for that set of lights.

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I don’t have any smart lights, only smart switches but I have a question that is somewhat relevant to the OP 's needs.

I’ve got scenes, and used to have routines, that turn on smart dimmers to specific levels.

My experience is that SmartThings sets the dimmers in two steps, first turning on, then setting the level. Turning on brings the lights up to whatever level was last used. So if I’d like a low level but the light was last at 100%, I get a 100% blast before it dims down.

Question: do smart bulbs work the same? So the OP’s single bulb might come on super bright before the level and color get changed?

The “Set Level” command turns the light on at a specific level. So if the light was on at 100% and then turned off, if you set the level to 50%, it will turn on at 50%. It will not go to 100% and then dim down to 50%.

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Sounds like you will need a combination of Smart Switches and Smart Bulbs.

Since it’s a remodel, you can run the necessary wiring now. For Smart Bulbs, you want an always on circuit. You can still hard wire Smart Switches to control the on/off/scenes of the bulbs through Apps such as webCoRE. The hardwired Smart Switches will not be physically connected to the Smart Bulbs.

There are a handful of Smart Switches that allow multi taps up and/or down that act as additional buttons! Even up to 5 taps in either direction! Double tap down, turn off all lights, double tap up turn on color bulbs, triple tap down, set mood to sexy time, etc…

Definitely put the fan on it’s on Smart Switch. Lights without color also should go on a dedicated Smart Dimmer.

For each separate circuit, just install the appropriate gang box. I have at least 4 areas where I changed the configuration of the gang boxes. Below is a 2 gang box that I changed to a 4 gang box.

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It seems that SmartThings does not do this. For both Scenes and commands via Alexa, I have always gotten a distinct two-step process where the dimmer is first turned on, then the level is set.

Happens with Zooz, Leviton, and GE Z-wave plus dimmers.

I’m not seeing that behavior. Just recorded a quick video of how mines work. I have a combo of GE Z-Wave 12000 series and Z-Wave Plus 14000 series…

Thank you all for you comments. I’m in the UK and am taking this opportunity to rewire the house to work with smart devices.

Rontalley, I had also thought of a combination of smart switches and smart bulbs.

For the normal bulbs I was thinking of putting them on the same circuit as the fan (these will be non-dimming and just regular on/off - is there a specific reason why I should not have the regular bulbs and fan on the same circuit? I need to do 3 bathrooms and thinking of cost of too many seperate components.

For the single bulb that needs to dim and change colour I will use a smart bulb. I hadn’t thought of an always on circuit but it makes sense and to use a scene triggered by a button press to turn on, dim and change colour. I like the idea of a single switch where a normal on/off would activate the normal lights and a double press would activate night profile ie single bulb dimmed and amber/red.

I am currently using smartthings and thinking of installing Home Assistant. Would this be possible with these applications or so I need to investigate webCore as mentioned. Finally would smart switch it recommend to do the activation of the scenes? Thanks again for all your help.

The History in the app shows what I’m seeing.

“Fireplace” is a set of two LED can lights controlled by a Zooz ZEN27 dimmer.

Here’s a Leviton DZ6HD-1BZ dimmer. Log shows the On command after the level set but they actually happened in the opposite order, On then level.

I use either SmartLighting, CoRE, or webCoRE for all of my lighting automations. When I use the Set Level command, I get the action as viewed in the video posted above. So SmartThings does use Set Level as an “On” command and from my experience, the level turns on at the desired set level.

From my experience, I only see the behavior you are describing if I turn on a light manually but have it programmed to go to a default level based on conditions set. For example:

If time is between sunrise and sunset and light switch is turned on, then set level to 50%. Doing it this way, the light will come on at the last level it was on then dim to the programmed set level. This is different from turning the light on programmatically.

Maybe that’s what you are seeing?..


Looks like the problem is Smart Lighting. The devices I posted are usually “grouped” by using a virtual dimmer and the mirror capability of Smart Lighting.

In the event log, I see the Mirror automation sends an “on” command followed a few milliseconds later by a “setlevel” command.

The most common thing I do is trigger a Scene, either by tapping a Scene icon in the new STSC app or telling Alexa to activate a scene. So there might be several devices getting commands quickly.

FWIW, all devices are local using stock DTHs.

I’ll play with this some more.

Apologies for totally hijacking the thread!

Aww…Yeah, I can totally see how that would be an issue using SmartLighting.

Try this!! Should easily solve your issue.

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