Advice for US new construction lighting

Hey all! I’m prepping for complete gut home remodel, and am considering what kind of smart home system to install.

For lighting, I find the argument for smart switches instead of smart bulbs to be compelling. Now the question is what kind of lighting control to install. I’m leaning a bit towards Lutron HomeWorks, and I’m curious to hear what people’s experience with that system has been. I’m particularly wondering about system reliability when you have wall switches that don’t directly control the electric circuit for lights. From a brief look online, I don’t see complaints about HomeWorks crashing and leaving all the lights unusable. But it seems like that’s a potential failure mode of the HomeWorks architecture.

I’m also curious about what people recommend for a physical wiring architecture to future-proof the house. I’d like to minimize the need to ever rip open the drywall, as long as future-proofing isn’t too expensive up-front. It seems like wiring lighting switch boxes to an electrical closet rather than a light circuit would give one maximum future flexibility. I haven’t tried calculating what the copper costs would be, but wiring each bulb box individually to the electrical closet would also maximize future flexibility. If that’s too much money, then I’d just wire each light group to the electrical closet. I’m planning a 3000 ft^2 home on three levels, and am thinking one small electrical closet per level would minimize the total wire length in the walls.

Any feedback people have is welcomed, this is my first time thinking about smart home design.

Unfortunately I don’t have any advice for you as I am in the same position you are. Would love to know what other things you are even thinking about to make your home “future proof” for home automation. Outlets, Internet wiring, etc. ? If you would be willing to share any useful resources you have found that would be great also. I’d be happy to do the same as I start to figure things out.

I know you posted a while ago but when I saw your question show up in an HA update email today I thought I could describe what I’ve settled on.

I had a water leak that is forcing a gut remodel. All new everything except the structural walls and plumbing, although that’s getting modded as well since I am remodeling bathrooms. For the lighting everything is LED color temperature adjustable with some RGBW units. I have track lighting in places where ZigBee is used to control each light. Everything else is ZigBee or DMX.

I decided to go back to the future and use structured low voltage wiring to a relay panel for the basic power control. Even though everything is ZigBee or DMX I wanted a fail-safe mode in which the lighting switches would still work if the HA/ZigBee or DMX controls fail, with 3 / 4 way switches working as expected in halls, large rooms and stairways. When the HA is working the fancy features will be available. Otherwise it’s basically on/off (no dimming). One assumption I am making is that when physical power is removed from a ZigBee light or DMX ballast that it will come up in it’s last setting when power is restored. This seems to be a safe assumption so far.

Each lighting fixture (or group of fixtures I’m OK running as a group in fail-safe mode) has a romex home run to the relay panel. Each wall switch is an SPDT center-off decora switch with its own Cat5e run to the structured wiring center. I use Cat5e not as ethernet, but as a bunch of wires right now to carry low voltage to the SW panel although I could swap out or add more smarts to the switches later.

The relays for each lighting home run are latching relays rated at 50A/240V (it’s what I could find) or solid state relays controlled in turn by low voltage latching relays. In fail safe mode each light switch will control the relay coils directly at low voltage. Pressing and releasing the top of a switch pulses closes a contact that pules the relay ON. The bottom switch pules the relay OFF. That’s why latching relays and momentary center off switches are required.

A jumper panel configures which half of each switch turn which relays on or off. Simple diode logic allows each half of each switch to control any of the lights on or off functions independently. It’s actually pretty easy to figure out the jumpers and change them. Three, four or multiway switch configurations are trivial. The only limitations are that there is no “toggle” or dimming in fail-safe mode.

When HA is running it can disconnect the switches from the relays, sense their state, and control the relays directly. Usually it will just leave the power on to each light and control it via ZigBee or DMX. The fail-safe control is a bit more complicated than this but it boils down to a normally closed relay that supplies power to the switches sufficient to engage the relay coils. As long as HA provides a heartbeat AND the power to the HA systems is up then the relay is held open and enough power for HA to sense the switches (but not activate the relay coils) is supplied instead. If either fails then the relay closes and the system switches to fail-safe mode. A separate battery backed power supply is used to power the switches and relays. The HA and relay panel are separate boxes so I can just pull the plug/remove the HA box and everything still works.

So why all this hassle? Three reasons:

  1. It’s fun.
  2. No single point of failure.
  3. If I sell my place or decide HA toys are no longer fun I can just pull the plug and still have something that will be NEC compliant and any building inspector will approve.

What I’m wrestling with now is whether to use a microcontroller or FPGA as the main interface between the switches and the HA system. My concern is that with close to 50 switches (times 2 for each switch) guaranteeing low latency in HA may be difficult if it has to poll 100 binary sensors to see a brief pulse on one of them (or simultaneously on several).

Perry