Guides

This hub is the questions that block a purchase - the ones you have to answer before a product shortlist means anything. Will this fit my door. Does it stop working when the wifi drops. Where does the footage go. What does Matter actually change. Each guide answers its question in the first sixty words and then explains the mechanism underneath, because the short answer is what you came for and the long answer is what stops you buying the wrong thing twice.

How these guides are built

Products we claim to have tested: zero. Nearly every page in this category says it spent a month with a dozen locks on its own front door. We have not done that, we are not going to say we did, and stating it plainly is the point rather than an apology. What we do instead is specific and checkable.

We work from published manufacturer specifications and installation manuals - the documents that contain the backset range, the transformer voltage window, the battery chemistry and the magnet gap tolerance, and which almost nobody quotes back to you. We work from published standards: the BHMA and ANSI A156 documents behind a lock's grade, the Matter and Thread specifications, IP ingress ratings, and what each of those actually certifies. And we show the arithmetic: battery life against cycles per day, five-year running cost against purchase price, storage capacity against bitrate. When a number comes from a manufacturer's own claim rather than a standard, we say so in the same sentence.

Where the sourcing rules and the scoring come from is set out in full on how we pick, which is the page to read first if you want to know how much weight to give anything here.

Fit and installation

The most expensive mistake in this whole site is a lock that does not physically fit, and it is entirely avoidable with a tape measure. Will a smart lock fit my door walks through backset, cross-bore, edge-bore, door thickness and the obstructions that catch people out - raised panels, glass inserts, metal slabs, and a deadbolt that already needs persuading. Once you know the answer, how to install a smart lock covers the install itself, including the alignment check that decides whether auto-lock is safe to switch on.

Both of those assume a door that can take a deadbolt. Smart locks for storm doors covers the case where it cannot: a storm door slab is roughly half the thickness a deadbolt needs, so the guide explains the measurement, says plainly that no mainstream smart lock fits, and sets out the three things that do help instead. And once the lock fits, the door's exposure is the last physical question: can smart locks get wet reads what each maker actually publishes - IP ratings, temperature ranges, and the interior half that none of them rates - and explains why every one of them rules out a gate.

Two questions sit before the tape measure if the door is not yours. Can you install a smart lock in an apartment separates the two designs a lease actually treats differently - a retrofit changes nothing and keeps the landlord's key working, a replacement does neither - and sets out what to ask for in writing and how to leave the door as you found it. And what ANSI/BHMA grades mean for smart locks decodes the specification most often quoted and least often understood: two separate grading systems, numeric and lettered, from two different standards, neither of which tests the electronics - plus how to check a grade claim in BHMA's own certified product directory.

Connectivity and protocols

Protocol confusion is the second-biggest source of returns. Do smart locks need wifi separates what genuinely stops working during an outage - remote unlocking, away-from-home notifications, remote guest codes - from what keeps working, which for most locks is everything you do while standing at the door. Matter and Thread, explained deals with the other half: which devices need a border router or a coordinator, what Matter certification actually promises, and where it still falls short of the marketing.

The security half of the same question - what each radio exposes, and to whom - is separated out in smart lock security risks by protocol. It sorts Wi-Fi, Bluetooth, Zigbee, Z-Wave and Thread by where an attacker would have to be standing, which turns a vague worry into a short and mostly reassuring list.

One level up from the radio is the platform that ends up owning the devices. The best smart home ecosystem for security compares Apple Home, Google Home, Alexa, SmartThings and Home Assistant on the five things that actually differ - where a recording gets written, what still runs with the internet down, what is gated behind a plan, which radios each speaks without another box, and what each company has already done to customers who had bought the hardware.

Two questions people ask late and should ask first. Can you use your existing key with a smart lock has a mechanical answer rather than a brand one: a retrofit keeps your cylinder and therefore every key in the household, a replacement ships a new cylinder and new keys, and there are exactly three routes back to one key afterwards. And how many security cameras you need is a counting method rather than a number - entry routes rather than walls - which matters most on the brands that price cloud recording per camera, where the fourth camera is a purchase plus a recurring bill.

The third device answers the connectivity question least forgivingly, because the notification and the two-way talk are the entire product rather than a feature on top of it. Do video doorbells need wifi separates the three things buyers conflate - Wi-Fi coverage at the door, a home network, and an internet connection - because a doorbell behaves differently when each of the three goes away, and local storage is what decides whether an outage costs you notifications or evidence.

Power, weather and the physical world

Three guides deal with the part of home security that has nothing to do with software. How to power an outdoor security camera ranks the four real options - PoE, a mains spur, solar and long-life battery - and names the two improvised ones that cause most failures. Do solar security cameras work in winter answers the January question with the published charging cut-off: the camera keeps recording, but a lithium cell below freezing is not permitted to charge, which is a protection rather than a fault. And how to secure windows from break-ins is mechanism-first in the same way the sliding-door guide is: the factory catch is a convenience latch, so the fixes that matter are a second fixing point and a travel stop, long before anything with a battery.

Three more guides belong in this section. The siting half of the solar question is how much sun does a solar security camera need, which quotes what each maker publishes - eufy states two hours of direct sunlight a day, Reolink declines to give a number at all - and then explains why hours of daylight is the wrong measure. How to secure your front door is the companion to the sliding-door and window guides, and it starts at the strike plate rather than the lock, because a forced door almost always fails where three short screws meet a pine jamb. And how to secure a garage door covers the largest and least-watched opening on most houses: the emergency release, the service door, the opener's code generation, and the code-regulated door into the house.

When something already installed stops working

Two guides here are repair rather than research. Smart lock troubleshooting works the five lock failures in fix order, and three of the five turn out to be mechanical rather than electronic. Sensors that keep going offline does the same job for a perimeter: why a battery sensor drops off a Zigbee or Thread mesh, why the fix is usually a mains-powered device rather than a new sensor, and why re-pairing is the step with the lowest hit rate and the highest cost.

Storage, cost and the safety question

Local storage versus cloud recording is the guide that changes the running cost of a whole system, because it determines whether you are buying hardware once or renting retention forever. It covers what happens to each model during an internet outage, what happens if the camera is removed, and how to get a clip out as a file.

Two companion guides take the same storage question in the two directions people actually ask about. Do security cameras record all the time is the disk side: which cameras can capture continuously, why no battery camera can, and the arithmetic for how many days a drive really holds. How much data do security cameras use is the uplink side: why local recording barely touches your internet connection and cloud upload touches it constantly.

For anyone starting from nothing, what to buy first sequences the four layers - sensor, lock, doorbell, camera - in the order that makes each purchase inform the next, and says plainly why a camera is usually the wrong first device.

The two remaining guides answer the questions people ask before they will commit at all: whether a keypad or app-controlled lock is a sensible replacement for a mechanical one, and whether a doorbell earns its place as a first device. Both are written the same way as everything else here - the answer up front, the reasoning below it, and a plain statement of the case for not buying.

What most buyers get wrong

Researching the product before the constraint. Two hours comparing four locks is wasted if three of them need a bore your door does not have. Ten minutes with a tape measure comes first, always.

Reading only the guide that matches the thing they already want. The storage guide changes camera choices, the protocol guide changes sensor choices, and both change what a subscription is worth. They are not independent.

Treating a manufacturer figure as a measurement. A two-year battery rating is a claim made under stated conditions, and the conditions are in the manual. When we quote a figure like that, we name whose figure it is, so you can weight it accordingly.