10 smart ways to protect your home

Mockupancy is the idea that you can use technology to pretend you’re at home when you’re not. At a very basic level, that means practices like leaving a light on or a radio playing to deter intruders when you go away on holiday.

According to reformed burglars themselves, hearing a TV playing is a greater deterrent than more traditional security measures like strong UPVC windows, security gates or motion-activated lights.

But if you leave a TV on 24/7, it doesn’t stand up to particularly close scrutiny.

Estimates vary, but current thinking is that less than half of burglars are professional “career criminals”. More common are “crimes of opportunity”, committed by people who lead relatively normal, non-criminal lives most of the time, and only steal if they spot an easy opportunity.

So consider that an “opportunity-burglar” might well walk down your road every day, perfectly innocently, as part of their normal commute to a regular, everyday job. Over a few days they notice the TV is always playing, morning and night… and a closer inspection reveals the same lights are always on too, or that uncollected post is starting to build up in your letterbox.

Here’s where we can start to use smart technology to up the game.

A basic mockupancy scheme starts with smart plugs, or smart lights if you prefer. Rather than leaving a device on 24/7, you can use a smart plug or light on a schedule to make things a bit more realistic – particularly for longer absences, like holidays.

Any smart plug will almost certainly give you timers and schedules in its companion app, or you can use a service like IFTTT (if this, then that) to achieve the same ends. Ideally, you want the schedule to vary somewhat from day to day to strengthen the illusion. A few smart plugs connected to lamps, radios and TVs in different places in the house, all on varying schedules, will work even better.

You can bolster the illusion by getting a trusted neighbour to collect your post so it doesn’t build up in the letterbox. If you plan on taking your car when you go away, ask them to park in your drive so it’s not conspicuously absent.

That helps to mitigate crimes of opportunity. But what about more determined burglars?

There’s substantial evidence to show they also employ tactics like knocking on the door or ringing the doorbell to see if anyone’s home.

Should someone answer, they have a “ruse story” prepared – simple mistake, wrong home, offering a brochure or service door-to-door. In the absence of an answer they can either start to case the main property in earnest, or at very least, head around the back in search of opportunities like bikes or tool sheds.

Exactly how you implement this is going to come down to the smart tech you have at your disposal. But in this example, we’ll show how you could up the ante using two very popular devices: a Ring Video Doorbell, and an Amazon Echo smart speaker.

Ring and Echo integrate natively, so download the Ring skill for your Echo (if you haven’t already) then fire up the Echo app.

Tap on “devices”, then “all devices”, and locate your Ring doorbell.

Tap on the Ring doorbell to open its settings page, and from there you’ll see an option for “doorbell sounds”. Whatever you select in here will play through your Echo speaker whenever somebody rings your Ring.

Okay, so here’s the clever part. Instead of a doorbell sound, we’re going to use an audio file of something that should deter a burglar. A large-breed dog barking, or maybe people talking. You can record your own, or you can grab one from a free audio library. You want it to be long enough that it sounds convincing, and doesn’t obviously repeat or end abruptly.

Copy the file into the “Ringtones” folder on your phone to make it available to Ring and Echo. Depending on your mobile OS and the version of the app you’re running, you might have to set it on your Ring device before it becomes available on the Echo.

Turn up the speaker good and loud and put it somewhere near the front door before you head off on holiday. Now when our would-be burglar rings your doorbell, he’ll be greeted by the barking of an angry (but entirely fictional) Alsatian.

It’s not totally fool-proof. But would you risk it?

The examples we’ve described above can be implemented with minimal investment in time and money – you could start with a single, stand-alone smart plug.

But if you’ve got a more sophisticated smart home, like a HomeAssistant setup for example, the only limiting factor is how much time and effort you’re willing to invest. The beauty of a fully-fledged smart home is that you can program more or less whatever custom functionality you can come up with.

Now we’re not suggesting you replicate the tricks and traps from 1990’s cult hit Home Alone exactly, because dropping bowling balls on burglars and setting them on fire is more likely to land you in court than them. Deliberately engineering ways to trap or harm intruders is illegal in the UK, where we’re based, and in many other countries besides. But we can definitely borrow a few ideas!

A great jumping-off point is to introduce randomness to your mockupancy scheme. Instead of a pre-defined schedule, events like “lights on” are picked randomly from a table and last for randomised durations, so there’s almost no way to tell them apart from real, human interactions. The smart home community is known for its inclusive, sharing attitude, so you can find any number of excellent tutorials or even off-the-shelf code snippets to try out – like this one, or this one, or this one for SmartThings users.

Another great example that recently went viral was a homeowner that set up a motion-activated, high-powered water sprinklers in their driveway. Following repeated thefts from vehicles in their area, the Camerena family ordered a high-powered water pump from Amazon; coupled it with a standard infra-red motion detector of the kind used in motion activated lighting, and caught the moment it scared away a would-be thief on their Ring Video Doorbell camera.

If you really want to push things as far as you legally can (in the UK at least), the most extreme solution is probably an “alarm mine”, AKA “garage grenade”. An alarm mine is a device that uses motion or a tripwire to set off a “blank”, meaning a casing filled with gunpowder, to create an extremely loud bang and blinding flash. We cannot stress this enough: it is LOUD. If you have pets, or kids, or elderly dependents, think very carefully about whether you really need to go this far. But if you’re looking for the “nuclear option” in UK home security, this is it.

Alarm mines are designed to be stand-alone. The trip-wire can be stretched across a hallway or tied to the handle of a door or window. But if you felt the need to integrate one into a smart home system, you could use a simple linear actuator to pull the pin.

Now that we’ve gone… probably a bit too far on the home security front, let’s talk about some other leading causes of damage to property and how to prevent them with smart technology.

Let’s be totally clear: the true “best” mitigations for house fires revolve around good practice and risk assessment. Before exploring the smart options below, you should make sure you’ve taken care of the fundamentals.

Check each and every room in your home for potential sources of ignition: ovens, hobs, heaters, fireplaces, clothes irons, candles, hair straighteners, etc…

Now, for each one, do your best to isolate that appliance from flammable substances – fabrics being a prime candidate. So for example: in the kitchen, think about where you hang your towels. Are they above, or anywhere near, the stove top? Do you habitually hang them on the oven door? Are there curtains or blinds above the cooker? Are you storing kitchen roll, oils or plastic bags above toasters, ovens, waffle makers? You’d be amazed how many homes your author has visited where the occupants have installed lace curtains or towel rails directly over stovetops. All it would take is an errant spark, or a towel sliding off the rail, to start a serious fire.

Elsewhere in the home: are you using candles on windowsills? Is that electric heater far enough from the curtains and sofa? When you’ve finished using the hair straighteners, do you have a heat-proof mat to leave them on – or do you throw them on a bedside table or (even worse!) down on the rug?

Do you have smoke alarms on every floor? Ideally you need them in every corridor, especially the hallways outside every bedroom to ensure you’ll wake up if a fire starts at night. If you live in a period property, like many UK residents, you might have features like exposed beams or even coffered ceilings. Smoke flows very much like water (it obeys fluid dynamics), so it can cascade or “waterfall” over those features in unforeseen ways. It’s subject to things like the Coanda Effect, meaning it can pool and collect and stick to surface. Smoke alarms need to be at least 40cm away from those features to ensure the smoke doesn’t bypass them and delay the alarm. They must be at the highest point in the ceiling, and although some manufacturers say you can install them on walls, fire service professionals strongly recommend against it.

Another less obvious pitfall arises from the use of smoke alarms in, or nearby, kitchen areas. Smoke alarms specifically – not heat detectors – are photo-electric devices, meaning they work by counting particles in the air as they break a beam of light inside the device. Cooking unavoidably produces a lot of airborne particles (whether you burn the toast or not) and a photoelectric device will falsely trigger, with irritating frequency. The upshot is that many homeowners find this annoying enough that they end up removing the batteries while they cook… and then one day forget to replace them, and end up unprotected.

The same problem can arise with alarms near bathrooms. Humidity from showers, or aerosols (deodorant, hairspray…) both create very large numbers of airborne particles, which to a photoelectric detector are indistinguishable from smoke.

The solution? Use temperature-based fire alarms (heat alarms) in those areas instead of photoelectric devices.

In an incredible 38% of UK house fires, the smoke alarms failed to go off and alert the inhabitants. 45% of those cases were due to incorrect placement and 20% due to removed batteries – just like the examples above.

Okay, now that we’ve dealt with the fundamentals, let’s talk about how we can augment that with smart technology.

A great way to minimise fire risk with smart technology is to take advantage of presence detection, or even better, true occupancy detection.

The basic premise is as follows:

We fit motion detectors (e.g. Passive Infrared Sensors, PIRs) in rooms with fire-risk appliances, like the ones we’ve already listed out. Then, we fit a smart plug to each risk appliance. We configure the smart plugs so that they automatically turn off the appliance say, 5 minutes after you turn them on, unless there’s motion in the room.

That way, if you forget to turn the iron off and leave the room, the smart plug will automatically turn it off for you and prevent a fire.

There are some things to be aware of, however. PIRs need quite a lot of motion to trigger, so while this might work fine for activities like ironing, it won’t work nearly as well if you’re watching TV with the electric radiator on. It’s likely the automation will false-trigger pretty regularly and turn your heater off. You might think – “that’s okay, I’ll just wave my arms to turn it back on”. But we strongly recommend against setting up an automation for “if motion, turn the appliance back on”, because otherwise, it’ll turn on the next time you wander into the room and potentially cause a fire. Plus, PIRs just look for infrared, and all sorts of non-people-based things produce infrared. Sunlight, for example. The last thing you want is your hair straighteners turning on when the sun shines through the window!

So how do we solve it?

Like much of this guide, the best implementation for you revolves around the tech you have at your disposal. But here are some of the ways we’ve seen this problem successfully circumvented:

• • Instead of a PIR, you could use a microwave sensor. Microwave sensors are far more sensitive, across a far wider area, and they can’t be fooled like infrared sensors. That makes them much more suitable for a true “occupancy detection” implementation.

• • Use multiple factors to determine occupancy (not just motion). Our technical director once fitted a sofa with pressure sensors (the same kind that nag you to put your seatbelt on in the car) – so his system could reference it, plus power draw detection on the TV, to know if he was sat watching a movie. His implementation was more about pausing the movie when he got up to grab a drink or a slice of pizza – but it’s an ideal solution to this occupancy problem as well.

• • If you’d really rather stick to PIRs, you can try placing PIRs very close to the area you expect to occupy. Their sensitivity is inversely proportionate to range, so one or more PIRs located directly next to a sofa can sometimes still work very well.

It’s worth noting that if you take the time to nail down a solid occupancy detection system, you unlock lots of other cool and useful functionality in your smart home, too.

Robust occupancy detection is an excellent input to a home security system – or just a great way to check that family members got home safe, without the need for invasive cameras.

They’re used extensively in assisted living applications for that same reason – did a vulnerable individual get out of bed today? Did they visit the kitchen, the bathroom, and how often? Or what about turning off lighting and heating in unoccupied areas to save money and help to protect the environment. Or if you’ve got a multi-room audio system like Sonos, why not have your music automatically follow you around the home as you do your chores?

Occupancy detection is one of the harder things to get right in a smart home, but there are a lot of fun and useful reasons to invest the time and effort.

If you ask people to guess which factors are most likely to damage their home, things like burglaries and fires consistently come out on top. But it might surprise you to learn that in an average year, water leaks cause as much damage as all house fires, gas explosions and burglaries combined. UK insurance companies pay out around £2 million a day for what the industry calls “escape of water” – water leaks, to us humans.

A burst pipe can release as much as 220 litres per minute, although 40 – 50 litres is much more normal. Considering water weighs one kilo per litre, a burst pipe can result in three tonnes of water surging through your home in a single hour (!) – meaning a severe leak can bring down ceilings and walls as well as destroying your electronics, furniture and fabrics.

As if that weren’t bad enough, water leaks waste around 3 billion litres of water every single day, in the UK alone. In a world where more people die from a lack of clean water than from all forms of violence combined – wars, violent crimes, everything – that’s just an awful statistic.

This might not strictly count as smart technology, but a great first step to protecting your home is to make sure you know where your stop cock is – AKA shutoff valve. Turning this valve will close the water supply to your home and drastically limit the amount of damage a leak can cause. If a leak starts, this is the first thing you should do. In fact, you should go and try to turn it right now – particularly in hard water areas, they can seize up over time and be nearly impossible to turn. You want to be sure yours is still mobile before you need it.

We’ll talk about this in other articles, but simple practices like regularly checking the silicone sealant around baths and showers can go a long way, too.

Okay, now some fun stuff!

You may well have seen smart leak detector devices before – they’re typically a hockey-puck style device with a number of metal contacts on the bottom. If water bridges those contacts it closes a circuit and an alarm sounds, app notifications get sent, or whatever functionality you’ve programmed kicks in. There are variants that allow for a probe on a wire to be fished behind appliances or into wall cavities, and some include a temperature sensor to give an indication of freeze risk too.

These are what we’d usually term a “point sensor”, meaning they protect a single point in the home. They’re certainly better than nothing – but they have an obvious drawback, in that you need to successfully predict where in the home a leak will occur and place a device there ahead of time. They also don’t actually do much to stop the leak: they work by alerting you, and hoping that you’re in a position to intervene. This doesn’t help you if you’re out at work, or even worse, away on holiday. If point leak detectors are your only option, make sure you leave a key and the location of your stop cock with a trusted neighbour so they can step in if a leak occurs.

But let’s also talk about ways we could respond to a leak in a more meaningful way, or even better –prevent one outright.

One of the leading causes of water leaks – in the UK at least – is sub-zero temperatures. Most substances on Earth expand when they get heated. Water actually expands when it freezes, and when it has nowhere else to go, it destroys the pipe itself.

If you’re at home when a cold snap hits, you can just turn up the thermostat to keep your pipes above freezing. Running the water periodically will also help, giving the crystalline ice structures less chance to form and bond together. Plus, you can run the tap for a few minutes, then check the temperature of the water right out of the tap to be sure you’re keeping it well above freezing.

But it’s not always that simple. What if you’re on holiday, or it’s your holiday home on the other side of the country?

This is where a smart thermostat can help enormously. They can usually be controlled remotely from anywhere in the world. If you’ve got leak detectors with temperature sensors built in (or any other kind of smart temperature sensor for that matter) you can configure behaviours where if any of them trend towards zero they “call for heat” to the thermostat.

Depending on your smart home system of choice, you may also be able to trigger events based on meteorological (weather) data for a given location. So, if the forecast suggests sub-zero temperatures, temporarily increase the target temperature on the thermostat to compensate. (In theory, target temperature is target temperature, and you shouldn’t need to compensate. But in our experience, thermostats usually aren’t measuring the temperature anywhere near the worst freeze-risk locations at the extremities of the property, and boosting the target is a good insurance policy).

We’ve talked about how turning off the water supply to your property is the single most effective mitigation if a serious leak starts.

There are devices that will shut off the water supply automatically, in response to a command from your smart home system. Typically they’re a ball valve paired with an actuator of some kind, which you pay a plumber to install in line after your conventional shut-off valve, on the incoming water supply pipe for your property.

You can pair them with point leak detectors like the ones we described earlier, and shut off the water supply in addition to triggering alarms and notifications. Some devices, like this one, even have sensors and intelligence built in – so they can monitor the water supply and detect freshwater leaks without relying on point sensors at all.

We say freshwater, because not all water leaks are on the supply side. You also have waste water or “grey water” leaks – drains, sinks, and so on. These shouldn’t be completely discounted, and a few point sensors under sinks and shower trays can be a great idea, but the majority of water leaks do happen on the fresh side simply because it’s pressurised, and waste water isn’t.