Have a shop approximately 150’ from house with it’s own main, spliced from the house main panel. Have Smartthings hub and alexa. Will z-wave devices work or does the shop need it’s own hub?
What is Z-Wave’s range?
It is recommended to have a Z-Wave device roughly every 30 feet or even closer for maximum efficiency. While Z-Wave has a range of 100 meters or 328 feet in open air, building materials reduce that range. The more line powered devices in your Z-Wave network, the better, as they also act as repeaters to extend the Z-Wave signal. Z-Wave’s mesh networking allows a Z-Wave signal to “hop” through other Z-Wave products to reach the destination device to be controlled. If there is a wall interfering with this signal, all you need is a simple Z-Wave repeater or other line powered device to work around the wall so the signal can continue on to its final destination. Z-Wave supports up to 4 hops so the total home coverage will grow depending on the amount of Z-Wave products in the network. The maximum range with 4 hops is roughly 600 feet or 200 meters.
So Technically you’re within spec for Zwave, BUT you’ll probably need good repeaters or multiple repeaters on both ends - on the exterior wall nearest the garage and on the exterior wall of the garage nearest the house.