Which Smart Sensors To Buy (And 5 That Should Be In Each House)

by | Smart Devices

Smart Sensors are one of the most important elements of your smart home. They provide eyes and ears to your smart home to use for environment-based triggers for automation rules. There are many hundreds of smart sensors and this article gives you a selection of best sensors across five categoreis that you can buy.
Sensors (including water sensors) are often overlooked when buying smart homes devices. They are not as exciting as lights or heating controls but without them, your smart home is just a bunch of expensive gadgets that you can manually and remotely control from your phone.

There are many types of sensors, but we recommend to prioritize the following sensors:

  • Multi-sensors
  • Door and Windows Sensors
  • Leak Sensors
  • Temperature and Humidity Sensors
  • Smart Smoke Detector & Carbon Monoxide Alarms

Sensors are so important that two of the seven devices in our under $250 smart home starter kit is multisensor and a device to use it.

Have questions?
See the answer to the most frequently asked questions on sensors below
Which sensors should I buys first?
See below the list of the sensors you need to buy in the matter of priority

  • Motion sensors (usually a part of multisensors) should be first as they one of the most useful devices to control your lights. Place sensors in most used rooms (like kitchen, corridor or bathrooms) and you will be not only saving energy but also having troubles remembering where is your switch
  • Door/Window sensors covering all key entry points (doors, windows) to the house and linked to the smart home will make your security system secure and intelligent. Do not forget good presence detection rules to avoid frustrating false alarms and convenience of use
  • Leak sensors will give you a piece of mind and save you a lot of money and stress from pipe burst accidents
That type of smart sensors exits?
  • Motion – detect the heat of body to identify any motion around the sensor. Usual range is around 6 meters. You will struggle to find separate smart motion sensors and they are usually included in multisensors. The separate motion sensors are only available in closed systems like Hue or IKEA Tradfri
  • Temperature and humidity – provide temperature and humidity reading. Can be for outside and inside use
  • Multisensors – combine motion, temperature, humidity, luminance and burglar sensors
  • Door/Windows – signal if the door or window open or closed
  • Leak – determines if there is an excessive amount of water which is usually related to pipe burst of appliance issues
  • Moisture – help you to understand when you need to water plants
  • Smoke and Carbon Monoxide detectors – triggers the alarm if smoke or high CO2 levels detected
Zigbee, Zwave or RF – what protocol for sensors should I use?
  • Wired – wired devices are the cheapest to run, but most expensive to install if you did not have them when building the house
  • RF (433 MHz)– also cheap and potentially the most energy-efficient wireless sensors. Cons: they are only communicating one way and less reliable. They are also never combined with any other sensors and cannot tell you when they are about to be out of battery
  • Zigbee products are usually cheaper than the zwave-based competition. The weaknesses are the consequences of the protocol as they cannot be always easily connected to any other zigbee hub. Zigbee protocol is also can be less reliable and have a smaller range.
  • Zwave is the most expensive but at the same time the most reliable protocol. You can fine-tuned for your zwave devices to your needs (for example set sensitivity level and the frequency of updates) and report many parameters simultaneously.

The recommended approach would be to buy z-wave sensors for the most important areas (like leak and motion sensors at the most frequently used rooms) and zigbee-based sensors for the rest.

Our top pics for best smart sensors


Aeotec Multisensor 6 is a versatile multisensor which can be powered by USB and configured to your needs (level  of sensitivity to avoid pet false alarms and the frequency of updates for battery management). It combines motion, temperature, humidity, and luminance to empower the most intelligent automation rules.


Two factors important when selecting simple devices like door sensors – (1) how reliable are they and (2) which one gives the best value for money. Schlage Door and Window Sensor doing great at both. It is a very reliable sensor that is easy to install at a very reasonable price. As a bonus, it can work with wired sensors and also combined with a temperature sensor.


Fibaro Z-Wave Flood Sensor is a reliable sensor that can use battery or external power. It can also be connected to the external water probe and has an internal alarm (although not very loud). It is using zwave so can integrate easily to the majority of the hubs.

Best Smart Multisensors

Multisensors are the most versatile type of sensors with the single device being able to track motion, temperature, humidity, luminance and burglar alarms. They are small and neat devcies with at least a one year of the battery life. It is hugely dependent on the model and frequency of trigger events, so we recommend to think about external power for the most important sensors.

The installation process is very easy, but a good planning of where you should place is important to maximize the value of the sensor.

Common automations:

  • Switch on lights at the motion and it is dark inside
  • Turn on heating if the temperature falls below certain degrees
  • Turn on an extractor fan if humidity levels in the kitchen are high


Lights automations only require motion and luminance sensors, so Dome sensor would be the best option for value for money. It comes with a magnetic dome base that you can easily adjust angle and positioning. It has a decent battery life, can be easily installed and quick pairing to your Z-wave hub.


Aeotec Multisensor 6 is the best choice for general use. We like it because of its quality, ability to be powered by USB and configured to your needs (level of sensitivity to avoid pet false alarms and the frequency of updates for battery management). It combines motion, temperature, humidity, and luminance to empower the most intelligent automation rules. It can also be installed using ceiling recessor


  • If using in a busy area consider using the external power source
  • Reduce the sensitivity of your sensors to reduce pet alarms
  • Place in the area that will maximise use of sensors. For example above kitchen sink to track motion, temperature and humidity

Best Door/windows sensors

Door/window sensors are simple – they will tell you if doors or windows are open or not. Some sensors would also combine temperature and motion sensors (like this from Fibaro). Battery life is usually at least a year but depends on the frequency of the door/window use.

The installation process is simple with the bigger part of the sensor to be installed on the frame. No need to screw the sensor as the included double tape would serve the purpose.

Common automations:

  • Perfect for smart security systems: detect if somebody entering your house when you are away
  • Check if the fridge was open in the night
  • Switch on the lights when you came home late (so no motion sensor required)
  • Switch off air conditioning if windows are open


We recommend Zwave for the most important sensors as they generally more reliable comparing to Zigbee. Schlage Door and Window Sensor if your best choice for reliability, ease of installatin and a reasonable price. As a bonus it can work with the wired sensors.


Zigbee sensors are almost twice less expensive comparing to Zwave at almost no loss of functionality. Visonic MCT-340 is the best of existing sensors on the markets at the very reasonable price. In addition, it also acts as the temperature sensor. Cons: some users were reporting minor signal loss issues.


  • Check out Konnected if you already have connected wired sensors
  • You can also connect one extra wired sensor to some devices to avoid paying more

Best Leak Sensors and Water Sensors

Leak sensors can save you a lot of money and stress in some cases. Over 5 million people a year experience flooding in US due to pipe burst with average damage ranges being between $3,500 down to $25,000. This can easily be avoided with the leak detectors and water shut off valves.

Leak detectors usually installed in the areas that are at the risk of being flooded. This means you at least need to cover your washing machine, dishwasher, and sinks in each of the bathrooms. Some sensors would have built-in sirens, but they are not very loud. Others would be able to use external electricity, but the internal battery would normally last at least couple of years.

Installation is very simple – you just need to place the sensor where the sink can happen.

Automation examples:

  • Water leak shuts off the mains valve, fires a siren or Chromecast notification, notifies all the family members


Fibaro Z-Wave Flood Sensor is easily the best-looking sensor around, but this is not the reasons we recommend it. It is a reliable sensor that can be connected to the external water probe and has an internal alarm (although not very loud).


We have been a long time admirers of Aeotec and the third generation of Aeotec Water Sensor 6 highlights the reasons why. Extremely reliable device combined with a temperature sensor and a battery to last almost 3 years. In addition, there is an option to use a docking station for power via USB and connecting two extra wired sensors. Cons: a bit more more expansive than Fibaro


Temperature/humidity sensors

Sensors of this type serve a simple purpose – they report temperature and humidity. Depending on your use case, you can buy outdoor or indoor sensors. Installation is very simple and usually, you just glue it to the surface using the double tape provided. Note that temperature sensors are not significantly cheaper then multisensors, so think about the practical ways to combine with other sensors and use multisensors instead for practicality.

Common automations:

  • Switch on air conditioning if I am home and when the temperature is above X degreed
  • Make kitchen light blue between 7am and 9am when the temperature is below X degrees outside


Xiaomi Aqara Temperature Sensor is the best Zigbee temperature and humidity sensor from Xiaomi. It is very well priced, can work outside and have good battery life.


HEIMAN is a relatively new name in the smart home industry from China. Their Zwave temperature and humidity sensor is a reliable and neat looking sensors with good reviews


  • Do you really need the outdoor sensor? Online weather services nowadays give a pretty accurate reading
  • For the comfort of your home, adjust heating to the temperature outside

Smart Smoke Detector & Carbon Monoxide Alarm

Smoke detectors saved many lives and it is mandated by law for you to have one in your house. Existing “conventional” sensors are good at alerting of accidents when you are at home, but what if you are not? That is where smart Smoke Detector & Carbon Monoxide sensors useful. You can set up automations to alert you and anybody in your family regardless of your location.

In the majority of the cases sensors also combined with sirens, so you can use sirens for any other important notification events.

Installation is relatively easy and usually can be done without the external help


First Alert 2-in-1 Z-Wave Smoke Detector & Carbon Monoxide Alarm is a standard smoke and carbon monoxide alarm, except it is using Zwave to connect with your smart home hub. Quick detection and notification with low battery usage make an easy choice


Nest is building an upper-quality eco-system of smart home products.
Nest Protect Smoke and CO Alarm is not an exception and offers robust build, reliability, so we are liking all but price. They are also no big on local API, but still a very strong choice for smart alarm sensor.


  • Consult with your local rules and regulation to ensure compatibility
  • Periodically test sensors