Water is excellent when it comes out of the tap on request, but when it slowly drains under the sink or around the old washing machine, it rots the floor or floods a room, it becomes an expensive threat. Wirecutter recommends iHome Control Dual Leak sensor: works on Wi-Fi (no smart home hub required), has super long battery life and includes two sensors, allowing it to detect leaks in two different locations. It can also fit under and around anything that might leak, including fish tanks, dishwashers, hot water heaters and, yes, beverage pumps.

Fibaro also offers leak detectors designed for people who already have smart-home platforms based around Z-Wave or Apple HomeKit hubs. If you use one of these systems, the Fibaro sensors are excellent and can also be used to detect temperature changes.

Freezing sensors

Along with the free flowing water, frozen water is one of the biggest causes of home damage. We are talking about frozen water pipes, which then reserve, expand and burst, creating expensive fountains in your basement. Like leak sensors, frost sensors are small devices that constantly monitor the temperature of the object or area they are in contact with. When you put one on the inlet water line, it will send you a notification or text message that you will need a lot of towels if you do not do something fast.

If you already have a security system, such as Call Alarm, SimpliSafe or Abode, you can get a compatible freeze sensor to work with it. If not, you have a few options. Both the Honeywell Home Wi-Fi Freeze Water Detector and Roost Smart Leak Detector connect to the Wi-Fi network and the smartphone without a hub. Some sensors include probes or contacts that need to be in contact with the object they are monitoring, while others detect the air temperature around it and warn you when it becomes low enough to risk a problem.

For more pipeline protection, look for water flow measuring devices, such as the Phyn Smart Water Assistant, which not only detects leaks, but also when ice begins to form in your home's living facilities. It sends you a text alert. before a pipe bursts and can also be combined with a shut-off valve to automatically cut off your water in an emergency. For monitoring purposes only, Phyn costs three times more than most other sensors. It's a great investment, but it ensures leak detection for your entire home.

Smart smoke alarms

Photo: Michael Hession

Most homes already have smoke alarms, often more than one, and are an essential safety feature for anyone. But they have a major shortcoming: they are only effective if you are actually at home to hear the siren leaving. A smart smoke alarm does this, but it notifies you when you are gone, allowing you to call firefighters and a trusted neighbor to ensure a quicker response and safety for people living nearby.

Our favorite is Google Nest Protect, which senses both smoke and carbon monoxide. Roost smart battery allows you to turn ordinary smoke alarms using 9 V batteries into smart ones. For people who own an Alexa speaker, the Alexa Guard feature, available to most Echos, acts as a smart smoke alarm, listening to the sound of your normal smoke alarm and sending you an alert if you hear it. (All of these devices send notifications to your smartphone in a smoke event.)

Temperature sensors

Photo: Rozette Rago

In addition to helping you adjust the climate in your home, temperature sensors can announce changes in locations that are critical to temperatures, such as wine cabinets, humidifiers, cribs, or pets. Let's say the heater in your anaconda cage goes out in January. A temperature sensor can warn you about the problem, giving you a chance to fix it before the snake cools down. Most temperature sensors are small, the size of a match book and can be discreetly hidden. If you connect one to a smart speaker, such as the Amazon Echo, you can set custom ads, such as "the snake is cute," to warn you of a problem. Some of the above-mentioned frost sensors work as general temperature sensors, but we also like the Eve Degree sensor for Apple HomeKit users. In addition to being a smart sensor, it offers a display that lets you see the temperature without having to open an application on the iPhone.

Contact sensors

Photo: Rozette Rago

Use on doors or windows to determine if something is open or closed, contact sensors are usually part of a security system that alerts you when an intruder enters your home, but can be used in many other practical ways. Protect your belongings: A contact sensor from the fridge can announce your door open so you can close it before destroying your food. One on the garage door works the same, letting you close it before you get too far from home (and a smart garage door controller allows you to remotely lock it).

If you have a valid liquor cabinet or other storage space, you can set up a contact sensor that lets you know when your hands are going where they shouldn't. If you have small children and worry about accessing certain parts of the home, contact sensors can quickly alert you when small hands push a door. One basic Wi-Fi sensor we like is Monoprice Stitch: It's a bit bulky, but doesn't require a smart home hub. It also works with Alexa routines, which means you can program your smart speaker to make ads like "the beer fridge was open." People using Apple's HomeKit system should look at the Fibaro Door / Window sensor.

Some of the sensors included here combine more sensing capabilities, such as motion and temperature, into one device, so you can save some money by getting something that doubles. Placing sensors around the house may seem like an unnecessary expense for the overly cautious - but compared to the cost of major repairs to plumbing or fire, you'll get a bargain.

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