Multiple (two) hubs on one network?

The stronger your Wi-Fi, the harder it will be for your zigbee signals to get through. Wi-Fi, particularly boosted Wi-Fi, drowns out zigbee. So the more you do to strengthen the Wi-Fi, the weaker your SmartThings zigbee network will get.

There are many ways to make zigbee and wifi co-exist better, but almost all of them rely on zigbee doing channel hopping, and the smartthings hub does not do this. It’s just a very inexpensive device and consequently it has a somewhat fragile network.

First define the problem

As far as “someone will solve this” there are many ways to solve this if you are not using SmartThings. It’s not that big a deal. Wi-Fi probably would cover the 40 foot range anyway. The Kumostat sensors are very well engineered with a range even longer than Wi-Fi. Vera solve this for Z wave by allowing two of their hubs to be connected via ethernet. Even with SmartThings you can solve it easily just by making each building its own location and giving it its own hub.

So I don’t think an Internet search is going to help in this case. You can’t change the way SmartThings is architected. So most of the solutions that you would find for other controllers will not apply.

You just have to decide what is the most important thing for your particular use cases at your particular house.

Many solutions already exist for automating an outbuilding

You could use a vera hub in the outbuilding and it wouldn’t even need Internet access once you had set it up. Build the second network inside the main house and then move the whole thing out to the outbuilding. Done.

If you need events in the outbuilding to be triggered by things that happen in the main building, then you have to have some kind of connectivity. You could build parallel systems, maybe with Kumostat sensors. You could only use Wi-Fi devices in the outbuilding. Or you could use two vera controllers.

If you insist on running everything off of a single smartthings hub and for whatever reason you insist on not just using WiFi devices in the outbuilding then you’re going to have to build a zigbee/zwave backbone to get signal out to the outbuilding. It could be possible. It’s going to depend on what the weather is like outdoors.

But probably there will be a way that you could use a smartenit relay for zigbee and a good quality Z wave relay and put them in something in your yard to bounce the signal. You will have to have power there, obviously, so that could be expensive depending on what you already have available.

some people have been successful just putting a receptacle on the outside wall of each of the buildings with clear line of sight. Again, you would need one pair for zigbee and one for Z wave if you’re going to use devices of both protocols in the outbuilding.

choosing your solution

So again, there are many many ways to solve the issue of an outbuilding. I can’t tell you exactly what will work at your house because it depends on the local architecture and weather. And, of course, what protocols you want to use in the outbuilding. But there’s probably some ways to make it work although some ways cost more than others.

If you’re willing to use only zigbee in the outbuilding, you can get zigbee repeaters that are very powerful, the signal can definitely go three or 400 feet. Much farther than Z wave plus. But these require some technical skill to set up and again, they are more expensive. But there are a couple of members who live in rural areas and are using them To reach outbuildings.

You also have to think about the walls that you were trying to get the signal through, which is why I mentioned the receptacles people put on the outside. You want to have a device near a window in each building so that you are bouncing through glass rather than through brick or insulation.

If you are using Z wave devices, you can use zwave association just in the outbuilding and that will reduce a lot of lag. Not every signal has to travel to the hub and back again.

Anyway, the point of all this is that you have to decide what is the most important to you. What protocols do you want to use in the outbuilding? If you are willing to just use Wi-Fi, everything becomes much much simpler. But it costs more.

If you are willing to use a separate hub to make a separate network in the out building, again everything gets much easier. But then you give up the coordinated rules.

Are you willing to add devices in the yard? Then you can keep just the one smartthings hub and probably use whatever devices you want to in the outbuilding.

Are you willing to take the time to really plan the backbone of the network? That makes a lot of difference.

So you need to pick which problem you want to solve. Don’t lock yourself in a box saying this must be the solution until you have really defined the problem and the priorities, including your budget. And be open to using a different set of protocols for the outbuilding then you use in the main house. As well as having two sets of rules. All of That will give you a lot more flexibility.

And look at your specific use cases. Do you need to have events in the main house trigger actions in the outbuilding? How much lag would be acceptable? There’s no one right answer to any of this, but the point is that different answers may lead to different solutions.

So I think most people can find a solution to automating an outbuilding. It’s not as simple as just plugging in another device, but it can usually be done. :sunglasses:

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A note about hops.

In zwave, each message is limited to a maximum of four hops. This is why We would like to put the hub centrally in the building both horizontally and vertically. You are reducing the total number of hops to each outer wall. But as soon as you throw in an outbuilding, yes, then maybe you want to move the hub because now you have at least two exterior walls you have to get signal through.

For zigbee, even though each hop is shorter, you are allowed 15 hops into the hub and another 15 out again. So 30 total across the network. That gives you a lot of hops to play with including if you have to zigzag around some obstacles, like maybe a second outbuilding that is in the way. Also, zigbee’s messaging protocol travels better through rain then zwave does. Plus it is possible to get some zig be pro repeaters designed for outdoors which are 10 times stronger than one you would use inside your house. For all these reasons, plus better battery life you will see a lot more Zigbee devices used outdoors then Z wave.

So just keep that in mind as you plan the backbone of your network. With Zwave it’s easy to run out of hops if you are trying to get to a second building. :disappointed_relieved:

I put an Aeotec Z-Wave Plus plug in switch in the barn on the wall closest to the house. There is also a Zooz Z-Wave Plus light switch in the house on the wall closest to the barn. There is nothing between the house and barn. Distance is less than 80’. Does not connect at all. If I put the Aeon switch on a 25’ extension cord, sometimes it’ll work (about 50’ from house now), usually only right after I plug it in, bit after a little while the hub can’t contol it anymore until I unplug and plug it back in again. Plug works ok if inside the house.


But on the interior walls, right? Not on the exterior walls with a clear line of sight between them?

Exterior walls typically degrade signal much more than interior walls. Sometimes the only way to get signal to an out building is to put a repeater right next to a clear glass window, Bounce signal out to an exterior wall plug on that building, from there to an exterior wall plug on the outbuilding, and then in through a window there. But then you used up three hops just to get to the other building. So it does get tricky.

Are there any WiFi door sensors?

The issue with Wi-Fi is that you can’t usually find them for battery operated devices because Wi-Fi is a power suck compared to zwave or Zigbee

Mains powered Wifi sensors–but many are in the $150 range

DLink and WeMo both make plug in WiFi motion sensors that have IFTTT, so you can get decent ST integration that way. And they tend to be under $40.

Monnit makes mains-powered wi-Fi contact sensors, but they can run as much as $200 each. They’re usually used for industrial uses. And there’s no good way to integrate them with SmartThings.

Connectsense has a line which has been popular with RV owners. They usually run on mains but can also run on batteries, although they will go through the batteries fairly quickly. Their " security sensor" is an open/close sensor. They also have a wifi motion sensor, leak sensor, light sensor dry contact device, and siren. But they run about $150 each, and like Monnit they don’t Integrate easily with smart things.

(Note the ConnectSense also makes some HomeKit compatible Wi-Fi devices.)

Another option for a wifi-based outbuilding is to use a Harmony Hub and/or a Phillips hue bridge. This can be a good way to get coordination with a SmartThings hub in the main building.

So if you want a totally Wi-Fi set up for an outbuilding, and you don’t need it to integrate with SmartThings, you can have one, but it’s going to be expensive if you want any sensors other than plug in motion sensors.


1. Kumostat: good ST integration, fairly easy setup, $59 bridge + $39 sensors, amazingly long range

If you’re looking for a long-range battery operated contact sensor with pretty easy set up , I’d recommend Kumostat. These are really nicely engineered, and they have a longer range even then Wi-Fi. There’s a good community created smartthings integration with them as well, or you can just use their IFTTT channel. You do have to buy their bridge as well, and since the sensors cost about the same as Z wave or zigbee sensors that ends up being a little more expensive. But I don’t think you can beat the range unless you go to zigbee commercial range which is a much more complex set up.

2. Zigbee Pro repeaters + regular ST zigbee sensors: complex technical set up, requires two pro repeaters, long range, use your regular zigbee sensors

First, zigbee as I’ve mentioned, allows for a lot more hops than Z wave, which gives you more flexibility in planning the layout. And it travels through rain better than Z wave.

In this set up, you use the same zigbee devices you would normally inside the buildings. But you use two pro repeaters with attached antennas to get the signal from one building to another.

But you’ll see from that thread that the technical set up can be a major project.

So speaking just for myself, I would probably go with the Kumostat sensors first, since there is a working SmartThings integration and the set up is easier.

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I’ve added a wiki article on how to automate an outbuilding. As always, free to add to it. :sunglasses:

What about two separate hubs and use IFTTT and virtual switches on the main hub to control the switches on the outbuilding Hub?

Because of the SmartThings architecture, you can only connect one ST location to one IFTTT account. So any one IFTTT account can only see switches that are owned by one smartthings hub. There’s no way to do a SmartThings to SmartThings recipe if there are two different hubs involved.

So you have to find a man in the middle who can talk to both smartthings hubs. That’s why the outbuilding wiki article mentions using text or an email as the If to IFTTT for the second hub.

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Gotcha, thanks. What about a Vera hub in outbuilding?

Depends what you’re trying to do and your exact setup.

Are you talking about setting up the vera as a secondary zwave controller to SmartThings?

That itself could be done, but it doesn’t give you any more range than any other Z wave device so it doesn’t solve the issue of an outbuilding that is too far away.

And vera doesn’t have an IFTTT channel, so it doesn’t address that issue.

If you want to run the vera as an independent network, sure, but then why not just run a second smartthings hub as an independent network?

Did you get a chance to read the wiki article on automating an outbuilding?

I did read your wiki. Def gave me a lot of ideas, and squashed some of my other ones, lol! :slight_smile:

What about Wink hub in outbuilding? It has a IFTTT channel.
Then use IFTTT to control simulated switches on the main ST hub in the house, and also have those ST simulated switches control the actual switches in the outbuilding.

When you put a different hub in the outbuilding, there it is. It’s just a separate network. Could be wink, could be Vera, could be zipato, could be Homeseer, could be indigo on a PC with a USB stick-- could be a second smart things hub with its own SmartThings account and its own IFTTT account. Could be 1000 miles away from the primary building it’s all the same.

The only question is is there way for that network to communicate indirectly to SmartThings?

If the outbuilding’s hub can send a text or an email, you can use IFT TT as a man in the middle and connect to SmartThings that way.

Or, as you point out, if the outbuilding’s hub has its own IFTTT channel, as some do, then you just use that. :sunglasses:

Same issues as always: how much is the lag, how much work is it to maintain two sets of rules, and do you work do you want to put in to be able to track the status of devices on the other hub?

Once you’ve decided to just put a second hub in the outbuilding, to be honest, it might as will just be SmartThings. If you want to track status of the other hub’s devices it’s very easy to create shadow trackers with virtual devices on both sides. ( something that’s very hard to do with most other hubs.) You’ll be familiar with the devices and the logic. And while you can’t run both from the same smart app, you can manually cut and paste a smart app from one to the other if you want.

So certainly you could use Wink, but I’m not sure what advantages you get unless you think it’s going to be more reliable or happens to bring a protocol, like Lutron, which SmartThings doesn’t have, and that you specifically want for the outbuilding.

I would totally put in a second ST hub in there but was told that you can only have one ST hub per IFTTT account.

Correct. That’s why I said [quote=“JDRoberts, post:49, topic:18557”]
could be a second smart things hub with its own SmartThings account and its own IFTTT account

Two hubs. Two SmartThings accounts. Two IFTTT accounts. No problem. :sunglasses:

Hub A has its own SmartThings account and its own IFTTT account. Same for Hub B.

You can’t directly connect them through IFTTT, but you can have one send a text message or an email to the other’s IFTTT account and it will work.

Essentially what I would like to do is install a door sensor, 2 multi sensors (motion, light, temp, humidity), smoke sensor, several light switches, and a fan switch in my garage.

I would want to be able to control the light switches from inside the house with scene controllers or mini remotes and via the ST SmartApp, etc. I assume I can do this using simulated switches in ST, one for each real switch in the garage using IFTTT. Turning a switch on in the garage would trigger an IFTTT recipe to turn on the simulated switch on the ST hub in the house. ST could then turn off the simulated switches and then use IFTTT to actually turn off the real switches in the garage.

The door/motion/smoke sensors would be a little more difficult, but I think I could also use simulated switches in ST in order for ST to trigger some SHM type stuff. Again a custom Smart App that could take the value of a simulated switch to control the values of a simulated door/motion/smoke/CO/flood sensor value would be awesome!

Don’t think I can do temp/humidity/light sensor info into ST, but I actually don’t really care about that. The Wink hub would use that to control the fan by itself.

I don’t really understand what you are asking for here. I suspect you mean a custom device type handler, not a smart app?

If so, it already exists. Mike Maxwell has a universal virtual device type handler which allows any one device to report as a different kind of device. So you could take your virtual switch and have it report as a motion sensor or an open/close door sensor.

I’m not sure about the specialty sensors like a flood Sensor and a smoke sensor. You’d have to check with Mike about that.

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Pretty sure that’s exactly what I was looking for, thanks! Will take a look and play with it tonight.
Thanks man!

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Thanks @JDRoberts, that’s pretty much what I was looking for, and a lot simpler than I thought. Hopefully he can add smoke/CO and flood sensor capabilities to it.
If so I’m pretty sure I can make this work with a Wink hub in the garage (assuming Wink can send IFTTT updates on open/close, smoke, and motion).

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Older thread, but has anybody come out with a hardwired zwave extender that anyone knows about or is this whole thread as good as it gets? I’m building a finished shed on my property that is out of range of my home hub, but I’m going to want to automate elements of the shed. I’m pretty comfortable with the idea of a second hub, but it would be simpler to extend via a hardwired device as I have conduit run to the shed to bring the network and power out there.