How do brick walls affect baby monitor range in the UK?

Why do brick walls cut baby-monitor range?

A dedicated parent-unit monitor is a short-range radio link. Anything solid on that line weakens it. BT states that published indoor range (up to 50 metres) and outdoor range (up to 250 metres on current video models) need a clear line of sight, and that wall material, thickness and dampness reduce range — with thick stone walls called out as severe. Brick in a Victorian or Edwardian terrace is the everyday version of that warning: dense, often damp, and usually more than one leaf thick on a party wall.

You do not need a decibel figure to act on this. If the path from the front bedroom to the back kitchen crosses a stair wall, a hall wall and a chimney breast, that is three obstacles, even when a tape measure says the rooms are close.

This page is about through-wall loss and how to count walls. It is not a buying comparison of radio types.

How do I count walls on a walk-test?

Count what the radio has to go through, not what the floorplan calls a 'room'.

1. 1
   Draw the straight line From the camera in the bedroom, imagine a straight line to where you will stand with the parent unit. That line is the path, even if you walk around via the stairs.
2. 2
   Tick every solid barrier Each brick or block wall, each closed door, the stair soffit and a chimney breast is one tick. Plasterboard on studs still counts as a barrier; it is usually a lighter one than solid brick.
3. 3
   Add the party wall if the line clips it In a mid-terrace the party wall is the thick shared wall. If your line runs along it or through a chimney breast built on it, tick it. Neighbours' Wi-Fi sits the other side of the same masonry.
4. 4
   Walk and tally At each stop write the running wall count next to picture quality. The first big drop often arrives when the count jumps, not when the metre count jumps.
5. 5
   Retest after moving metal Angelcare's UK interference note lists metal as the main household blocker, and names microwaves, routers, wireless speakers and phones as common sources. BT asks for at least one metre between either unit and TVs, PCs, routers or microwaves. Move those, then recount — do not add phantom walls.

What blocks a signal besides brick?

Mirrors, large fish tanks and concrete are in the same Angelcare list as reflectors or absorbers. A fridge against the party wall is brick plus metal on the same line.

Party walls, chimney breasts and damp masonry

Three UK-house details show up again and again on a brick walk-test:

• Party wall. Shared solid masonry. The radio path along that wall is longer than the room-to-room gap looks.
• Chimney breast. A brick lump in the bedroom or kitchen. Aiming the camera into it is a common own-goal; slide the camera along the same wall, still a metre from the cot.
• Dampness. BT lists dampness with thickness. An external side wall after rain is not the same barrier as a dry internal leaf.

Floors add another barrier when you go upstairs to downstairs. A three-storey loft path stacks floors on top of brick — that is a different walk, not a longer version of 'through one wall'.

What can a wall-count walk-test tell me?

It tells you where this pair of units still links in this house today. It does not grade the brick, and it does not stand in for a recall check or for safer-sleep practice. A clean path through one internal wall is not a prediction for the garden or the loft.

Official records and maker help pages describe interference and line-of-sight limits. They do not publish an all-clear for any wall type. No listing of a problem is not the same as a pass for overnight use.

Does range through brick change safer-sleep rules?

No. The Lullaby Trust says there is no research showing monitors help prevent SIDS, and that you should stay in the same room as the baby for the first six months. Keep the camera and cable out of reach; do not shift the cot to 'get through' a wall.

In shortIn short: count walls on the real path, including party wall and chimney breast. BT's metres assume line of sight. Move metal and the microwave a metre off the units, then walk again.