Do you need video if you can already hear through thin flat walls?

What are thin walls already doing that a monitor would do?

In a small flat the partition often passes volume — a cry, a cough, a partner’s TV. A monitor’s first job, hearing, is partly done. Video’s job is sight: has the baby rolled, kicked the sleep bag, or sat up silently. Those are different purchases.

Which? splits the market the same way: audio is two boxes and a speaker; video adds a camera and a screen. Its features article (August 2021, still cited from the buying guide) put audio Best Buys under £30 and the cheapest video Best Buy around £80. That £50 is the picture, not better ears.

How much faster does video drain the parent unit?

Which? asked 1,360 parents how long they expected a parent-unit battery to last. The average expectation was 13 hours. In the same piece (August 2019) its lab averages were:

A video unit left with the screen on all evening is the 7-hour job. VOX (screen off until sound) can stretch a charge; you then lose the always-on picture you paid the extra £50 for.

When does video still earn a socket in a small flat?

Sight matters when sound is a poor signal: a baby who wakes without crying, a toddler who climbs, or a room you cannot glance into from the sofa. It does not add hearing if the wall already rattles.

• You cannot see the cot from where you sit. Video is a glance. Audio is a guess.
• You mute the speaker for guests or a call. Which? highlights sound-sensitive lights for that. Video gives a picture when the volume is down; audio lights only show that *something* made a noise.
• Nights on a mattress in the living room, baby in the bedroom. The wall may pass a cry. It will not show a face-down wriggle. NHS / Lullaby Trust still want same-room sleep for the first six months — a camera is not a substitute for that rule.

How do you decide in one evening?

1. 1
   Do the closed-door test Put the baby (or a phone playing a recorded cry) in the sleep room, shut the door, and stand where you actually sit. If you hear it clearly, audio is duplicating the wall. If you hear nothing, audio has a job.
2. 2
   Price the picture separately Write £30 and £80 on a note. The difference is the screen. If you would not pay £50 to look, you are an audio (or no-monitor) household.
3. 3
   Budget the charge If you refuse to leave a parent unit on the mains overnight, Which?’s 7-hour video average is tight for a late bedtime. Audio’s 13.5-hour average matches the 13 hours parents said they wanted.
4. 4
   Skip movement pads for this decision A breathing or movement pad does not answer “do I need a picture through a thin wall?”. The Lullaby Trust says there is no research showing monitors prevent SIDS. Leave pads out of this choice.

Does “300 m range” matter in a two-bed flat?

Open-space range on a box is a radio claim. Which? tests through three rooms and then outdoors because walls, not metres, are the failure. In a flat the usual limit is a concrete stairwell or a trip to the bins, not a country garden. Audio and video both fail if the parent unit leaves the building; video fails sooner if the screen is on and the battery is the 7-hour class.

In shortIn short: thin walls already sell you the hearing. Which? priced a tested audio Best Buy under £30 and a tested video Best Buy around £80, and measured video batteries at about half the audio average (7 hours versus 13.5). Pay for video only if you need to see. If the cry already reaches the sofa, a second speaker is optional — and a camera is a luxury, not extra ears.