New house, zero automation now, what dimmers for future automation

[Linwood]

Sorry, appear to have opened a can of worms.
 
My understanding of the NEC is that you can have two branch circuits that share a neutral if your disconnect means will disconnect both at the same time.  Otherwise you could have current flow in the shared neutral after a tripped or shut off breaker.  The simple way to do that is a handle across two breakers, or a two pole breaker.  
 
The do it because it saves a bit of wire (one 14-3 instead of two 14-2 runs), which to me is dumb, dumb, dumb... but not illegal.
 
To the issue of multiple branch circuits in one box I know of no restrictions on that, and it is really common, especially in more complicated houses where you might have many switches in one box.  In my last house, for example, dock lights were switched from indoors -- but the dock had its own sub-panel outside.  The switched wire was run back into the house and back out, with no neutral in that box at all.
 
If multiple branch circuits make use of a neutral in the same box, and are not a multi-wire branch circuit with common disconnect, then each neutral must be kept separate and never tied together or mixed up.
 
Multiple branch circuits in a single box is otherwise known as "homeowner wiring discouragement" which is applied via a shock when you only turn off one breaker.   :blush:
 
If curious I can probably dig up a NEC and look up the code section for multi-wire branch circuits.  The other is harder to find as it's a matter of lack of reference, since I do not think there is anything to prohibit two circuits in a box.  I doubt it says "you can put two circuits in a box".  But maybe.

 

[Linwood]

Here's a decent writeup on the multi-wire branch circuit aspect.
 
https://www.twielectric.com/safety-and-energy-saving-tips/national-electrical-code-multiwire-branch-circuit/

 

[wkearney99]

It's certainly not my intention to get into a debate over nuances of code. 

Just that when discussing residential setups and discovering what come across like shortcuts that it's not unreasonable to assume something's not right and likely worth having an actual licensed electrician give it a once-over.

Especially if you're talking about spending a fair chunk of money on smart switches that will fry well before a breaker trips...

 

[wkearney99]

...and it is really common, especially in more complicated houses where you might have many switches in one box.  In my last house, for example, dock lights were switched from indoors -- but the dock had its own sub-panel outside.  The switched wire was run back into the house and back out, with no neutral in that box at all.

 
Well, if "complicated" means bodged up repeatedly over many years.. then yes, I get your point. 

I know, I had a house like that a while back.  Sub-panels all over the place, a rats nest of thumb-thickness electrical taped connections practically hammered back into tiny wall boxes... ugh, still gives me chills thinking about WTF moments opening a box naively thinking it'll be an easy job to add a dimmer...

 

[Linwood]

Well, if "complicated" means bodged up repeatedly over many years.. then yes, I get your point. 

I know, I had a house like that a while back.  Sub-panels all over the place, a rats nest of thumb-thickness electrical taped connections practically hammered back into tiny wall boxes... ugh, still gives me chills thinking about WTF moments opening a box naively thinking it'll be an easy job to add a dimmer...

 
Well, I really meant "necessarily complicated".  For example, a bunch of switches that control both lighting and motors and need more capacity than one 15-20 A circuit.
 
But I had a house in the country like you describe, in this case wires run all over the place, no rhyme or reason.  That's also a good counter-example to where I am now.  Building inspections here are fairly serious, and reasonably thorough. Where I was in the country they were lax (outbuildings when I moved there needed no inspection, even if power and water connected), and when they did inspect they often had no clue what they were looking for in many cases.  Nice folks, but pretty clueless. So it's not surprising what you found when you had electricians who might be a bit clueless also.  Or lazy.  

 

[CORT]

Another vote for RadioRA2 here.  RadioRA2 is a professional solution, and it shows.  My house's 100 device system has been rock solid for several years.  The initial "hoops" to jump through are not too bad for a DIYer.   Lutron's support is excellent.  For instance, I had a bad main repeater (something about defective memory) and Lutron replaced it without a blink.
 
One thing I've not seen reported in this thread is that Lutron's software for Radio RA2 is an excellent design tool.  It Is worth detailing your entire residence in the program listing all of the rooms, switch boxes, and loads.  Once you have done this, the program will give you a list of materials including wall plates.  You should start with Lutron's program before you buy their wiring devices.
 
Good luck!

 

[Linwood]

Things I'm finding as I move forward, in case useful to others....
 
It's annoying the dimmers cannot be reset to non-dimming (i.e. just off/on). I have two rooms with fluorescents, that I may one day want to change, but was not ready to do so now. Afraid to put dimmers on it, so put a caseta switch.  That works fine, but one day I may want to change again.  ONly two, and not really places I am likely to want to dim, but having a different type of switch is a bit annoying.
 
It definitely takes some getting use to the flat profile, 4-part switch in the dark when you just want to get some light.  I think it's a small issue, but I could see it being a real impact with a spouse.  And of course there's always "Google, turn on the lights". 
 
There really ought to be a home to which to send old switches, I have a huge array of them now, and cannot bring myself to throw them away.  I will, but sad.
 
Continuing to add new switches further apart, and not a hint of trouble connecting.  Very reliable so far.

 

[dgage]

In RadioRa2 software, you get to select how the switch/dimmer acts as well as how the dimmer turns off (2s ramp down as example). So you can choose to let a dimmer act as a switch in the software though I’m sure the local dimming up/down buttons bypass this but with normal operation, you can make a dimmer act like a switch in the software.

Doesn’t help you with Caseta but as you said, in case useful to others.

 

[LarrylLix]

In RadioRa2 software, you get to select how the switch/dimmer acts as well as how the dimmer turns off (2s ramp down as example). So you can choose to let a dimmer act as a switch in the software though I’m sure the local dimming up/down buttons bypass this but with normal operation, you can make a dimmer act like a switch in the software.

Doesn’t help you with Caseta but as you said, in case useful to others.

Insteon does similar to this. The switch only has hardware contacts while the dimmer version has an triac dimmer circuit. However both versions have the same LED display and can produce all eight different commands from one paddle.

 

[Linwood]

It's been 3+ months and I thought I would update. 
 
I put in a LOT of caseta dimmers, and a few switches.  They have worked flawlessly so far, with one nit, and one annoying "feature". 
 
The caseta pro bridge integrates with Home Assistant, and also has worked flawlessly for local control.  I have literally never had it miss either a switch status or an update.
 
The one minor nit is I have one dimmer on a 2 light circuit that leaves a tiny amount of light showing when off (related to the no-neutral nature where it powers itself by sending small amounts of current over the switched circuit when off).  There's a big capacitor they sent I think will fix it, but have not had time to try it.  It's noticeable unless you go into that hall in complete darkness.
 
The annoying feature is that the dimmers cannot be switches, they simply do not work on something like fluorescents, again I think due to the power issues and lack of a need for a neutral (to be fair, there are "pro" dimmers, and I did not try them to see if those work).  So I have several places I put in switches instead of dimmers, that one day eventually maybe I will want dimmers.  But probably not.  The switches require a neutral (frankly it would not have mattered for me as I had neutrals everywhere). 
 
I'm up to about 40 devices of the 50 limit, but not worried as I can put in a second bridge if needed.
 
The most handy feature of this whole thing has been the nano remotes.  I have now in three places extended the number of switches on the wall without having to put in a box or similar.  For example, a wall switch with a 3 gang switch: Mount the nano on the wall beside it in the right spot, get a 4 gang faceplate to cover the whole thing, and it looks exactly like a 4 gang box set of switches.   So anywhere you need an extra switch (e.g. where they did not put a 3 way wiring in) you can now add switches, easily, with no new boxes.  I also added one on a tile backsplash, just double sided tape, and it looks exactly like a switch that was cut into a box.
 
A lot of this is just amusing toys, but I find myself more and more using voice control.   Hands full, heading into a room and need light, just ask it be turned on.  Going out of the house "Hey google, turn off all the lights" is really handy. 
 
But so far I am very happy with Caseta, it seems dead reliable (admittedly only 3 months in), no issue in range (only a 2400 sq ft house, though I also put some in garage and attic), and solid integration with Home Assistant.