z wave 500 is good for 75 meters (246.063 feet) indoors. that’s more than enough for my house! the Minoston 800 Series Z-Wave Scene Controller communicates with my Samsung SmartThings v3 hub instantly from the first floor to the 2nd floor. i’m surprised it’s so fast since it’s send signal to my SmartThings hub and app then to Smart Life and Smart Life sends the signal my wifi bulbs. Also many of the commands have to run automations in SmartThings first, for instance “if light bulb is yellow turn orange, if orange turn red, if red… etc etc.” I’m using skyEdgeDriver which gives full control of the 4 button switch as far as i know, each button has 4 commands “pressed, press twice, press three time and hold.” i would also like to note its been 25 days and my batter still reads 100% on the switch and it gets used everyday, multiple times to control lights all over the house.
z wave 500 should do 75 meters indoor and up to 300 meters if its relaying off other z wave devices
It’s not a precise number. A lot of things can interfere with the signal, even mirrors or insulation inside the walls. And if you live in an adobe or cement house, as some community members do, you may only get 30 feet or so. So it’s always given as a “probable.“ or “typical. “ see the FAQ on wireless range and repeaters:
As I mentioned in my previous post, it’s not that precise. There are many architectural features that can slow down or block signal. For example, many people find that Z wave signal easily crosses an empty garage, but as soon as a car is parked there, the signal gets blocked. So the distances given are always listed as “typical,“ rather than absolute. Or even as a “maximum“ or “up to” with the understanding that what you actually get might be very different depending on the details of your specific location.
The outdoor numbers given are assuming clear line of sight and clear dry air. If it’s raining, the range might be a quarter of that number. If there are trees or buildings or vehicles in the way, that will also block signal.
For Z wave 500, the maximum outdoor range is about 600 meters, but nobody gets that consistently in real life. Most manufacturers will list the outdoor range as “typically 150 meters” just to keep customers from being disappointed.
As far as “relays,” assuming you mean “repeaters” that’s a whole different story that has to do with the architecture of mesh networks.
Zwave allows for up to four “hops” between a device and the hub. A hop is when a device which is capable of repeating (most mains powered Z wave devices) passes along a message, sort of pony express style. So now you get to add together the maximum distances between each two repeating devices along the route up to a total of four hops. Which ends up being about six times the distance that any one device can transmit. That’s true whether the route is indoors, outdoors, or a combination. So that’s how you can use zwave to cover a large home. This is also covered in the FAQ I already linked to.
yes, ranges on wireless devices are not precise but you shouldn’t run into any issues running zigbee or z-wave devices in your home. Correct Z-wave is limited to 4 “hops” which should be more than enough if needed at all in most homes seeing as modern z-wave is capable up transmitting around 300, times that by 4 and you have a 1200 foot range. Throw in some thick walls and say that gets cut in half you still have 600 feet, which is far for the interior of a home… Z-wave uses a low frequency, so going through walls and other obstacles in not as bad as zigbee.
If your z-wave is only transmitting 30 feet than you most likely have some sort of radio interference which can come from a range of things: if you are plugging a usb transmitter into your computer and or close to another device giving off an interfering signal you can run a USB extension cable. You can google what devices can be interfering or turn everything off then on 1 by 1 until you find the culprit but off the top of head like i sad, your computer, some cheap LEDS, baby monitors, cordless phones,
As I’ve mentioned before, I was a Zwave field tech before I ever bought my first SmartThings hub about 10 years ago.
Lots of architectural issues can interfere with zwave, it’s not just other radio signals.
You may have missed it in my previous post, but I was specific in the 30 foot reference:
And if you live in an adobe or cement house, as some community members do, you may only get 30 feet or so.
Adobe (found in the American West) and cement (found in Vietnam and some other parts of Asia) can, all by itself, block signal. And we have had some community members in the past who ran into that issue.
Other issues sometimes found in homes include chicken wire lathing inside the walls, metallic wallpaper, tile floors or walls, underfloor radiant heating systems, mirrors, aquariums, and large metal objects, including appliances and televisions.
Pretty much everybody at some point has been in some home where there were either Wi-Fi dead spots or cellphone coverage dead spots, and these are almost always caused by architectural features, not radio interference. It happens. 
That’s not to say that the other issues like interference from old style baby monitors and cordless phones, and these days, some drones, Can’t also be an issue. As you note, it can be good to check for those as well if you are running into trouble. 
just doesnt seem relevant to mention z wave in this conversation when wireless signals being impeded applies to all wireless communication. in fact z-wave will have the best chance of penetrating barriers 2.4 and 5 wifi and zigbee cannot.
All the same architectural issues will also apply to Zigbee and other RF protocols.
But I agree, the protocol discussion has gotten pretty off-topic for this thread. I’ll move it to a new one.