Guides · Sound · 13 min read · Updated September 2026

Quiet

The tradition’s still room, measured. What the manuals mean by stillness and what they keep out of a bedroom, the bells the temples hung and the chimes the shops sell, the house in decibels with the guidelines on it, a flat planned against its noise, and what the research on noise found in the children who lived under a flight path.

Oriented N 357°

Water

Fig. 01 A still lake at first light. The tradition’s still room is the room the lake describes, nothing moving and nothing sounding.

The tradition has no word for noise and a whole vocabulary for stillness. It wants the bedroom still, the study still, the hall not; it keeps water, clocks and chimes out of the room where people sleep and hangs a bell at the eaves where people arrive; and it reads a road that runs at a house as a sha before it reads it as a sound. The acoustician has numbers for all of it, and this guide puts the numbers on the tradition’s rooms: what quiet is in decibels, where a flat’s noise comes from, how to plan against it, and what the research found when it measured children who could not get away from it.

Stillness, in the tradition’s terms

The tradition’s scale runs from yang to yin, from movement to rest, and sound is on it as movement. A room with a fountain, an aquarium, a ticking clock or a chime is a room with something moving in it, and the manuals put such things where movement belongs, the entrance, the living room, the garden, and keep them out of the bedroom and the study, where the yin and yang essay puts rest. Rossbach, Wong and Too all give the rule as a rule about the bedroom, no water, no clock, no moving thing, and none of them mentions decibels; the reason they give is that a moving thing disturbs the still qi of the room, and the reason a sleeper gives is that they can hear it. The sleep guide puts quiet fourth among the ten arrangements and the research behind it is the strongest on the list after darkness.

The house in decibels

Fig. 01 The house in decibels. A quiet bedroom at night sits near twenty-five; the World Health Organization’s guideline asks for no more than thirty inside the bedroom at night and forty outside it, averaged over the year, and fifty-five outdoors by day. A fridge through a wall is thirty-five, a wind chime by an open window forty-five, rain on a roof fifty; conversation is sixty, a fountain indoors and close sixty-five, traffic at an open window seventy, a vacuum cleaner seventy-five. The scale is logarithmic: every ten decibels is roughly twice as loud to the ear, so the traffic at the window is not twice the fridge but eight or ten times. The tradition’s still room is the room below the two night lines, and its dislike of water and chimes in the bedroom is the scale read at its middle. The household figures are typical values, from the acoustic handbooks, at the distances given; the thresholds are the WHO’s European night noise guideline of 2009 and its community noise guideline. A wall of brick drops a sound by about forty-five decibels, a closed double-glazed window by thirty, a curtain by a few.

The scale is logarithmic, which is the first thing to know about it: every ten decibels is roughly twice as loud to the ear, so the traffic at an open window, seventy, is not twice the fridge through a wall, thirty-five, but eight or ten times. The World Health Organization’s guidelines put the lines on the scale. Its community noise guideline of 1999 asks for no more than thirty decibels inside a bedroom at night and fifty-five outdoors by day; its European night noise guideline of 2009 sets forty decibels, averaged over the year outside the bedroom, as the level above which it finds sleep disturbed and, over years, the heart affected. A quiet bedroom at night is twenty-five; rain on a roof is fifty; conversation in a room is sixty; a fountain indoors and close is sixty-five. The tradition’s still room is the room below the two night lines, and its rule against water and chimes in the bedroom is the scale read at its middle.

Evidence · What noise does

Basner and colleagues’ review of the auditory and non-auditory effects of noise finds the night effects best established: sleep fragmented and shallowed at levels the sleeper does not fully wake to, and, with years of exposure to traffic above the guideline, higher blood pressure and more heart disease. The clearest single study is Hygge, Evans and Bullinger’s at Munich, where the airport moved: children near the new airport lost ground in reading and memory after it opened, and children near the old one recovered after it closed, measured before and after in both places. Evans’s review of housing and mental health puts noise beside crowding and lack of control as the housing variables that matter, and a house at the head of a road, the tradition’s first sha, has all three.

What each layer takes off

Fig. 02 What each layer between a sleeper and the street takes off the noise, in decibels, as ranges on one scale. A plastered brick wall takes off forty-five to fifty, which is why the tradition’s solid wall behind the bed is also the quiet one; a closed double-glazed window about thirty, and the acoustic kind with laminated glass and a wide gap nearly forty; a single pane in the twenties; a stud partition about thirty, which is the wall most modern flats have between rooms. Earplugs worn well take off twenty to thirty. A rug takes ten to twenty off the footfall from the flat above and nothing off its voices. An open window takes off almost nothing, five to fifteen, whatever the glass, which is why the air guide’s morning window and this guide’s night window are two windows. A bookcase adds mass to a light partition and takes a few decibels; a heavy curtain takes two to five off the room’s own echo and none off the street. The scale is logarithmic in the ear: ten decibels off is a halving of loudness, and the difference between an open and a closed window is the difference between a street and a suburb. Figures are typical laboratory and field values for the constructions named, rounded to fives; a real window depends on its seals and frame, and a wall on its flanking paths. The WHO guidelines give the night-time targets the reductions are measured against.

The house in decibels above gives the levels; the drawing here gives what each layer between a sleeper and the street takes off them, and the layers are the tradition’s furniture with numbers on it. A plastered brick wall takes off forty-five to fifty decibels, which is why the solid wall the command position puts behind a bed is also the quiet one, and why a bed against the party wall of a flat with a quiet neighbour sleeps better than a bed against a stud partition, which takes off about thirty. Glass is the weak layer: a closed double-glazed window takes off about thirty, a single pane in the twenties, and the acoustic kind with laminated glass and a wide gap nearly forty, which is the one change in this guide that costs money and the one that works; an open window, whatever its glass, takes off almost nothing, five to fifteen, so that the air guide’s morning window and this guide’s night window are two different windows and a household with a street outside needs both, the one opened at first light and the other closed at dark, and the trickle vents the air guide draws so that the closed one still breathes. Earplugs worn well take off twenty to thirty and are the cheapest layer on the drawing. A rug takes ten to twenty off the footfall from the flat above and nothing off its voices; a bookcase against a light partition adds mass and takes a few; a heavy curtain takes two to five off the room’s own echo and none off the street, which is the one thing most people buy for noise and the one that does least. The scale is the ear’s, and the ear is logarithmic: ten decibels off is a halving of loudness, so that the difference between the open window and the closed acoustic one, thirty decibels, is the difference between a street and a suburb, and the tradition’s stillness, which it asked for in words, is available in glass.

Where a flat’s noise comes from

Four sources account for most of it. The street, through the windows on that side, which is the loudest and the one the tradition names as a sha when the road runs at the house. The neighbours, through the party walls and floors, television, footsteps, plumbing. The building, lifts, stair doors, the pump in the basement, the pipes. And the flat itself, the fridge, the boiler, the extractor, the clock, the fountain someone bought because a book said water brings wealth. The first three are fixed by the plan and the fourth by the household, and the plan is where the tradition’s reading and the acoustician’s agree without a word between them.

Plan 03 A flat planned against its noise The street runs along the bottom of the plan, the lift and the stair are on the right, and a neighbour’s television is on the far side of the left wall. The bedroom is in the top left corner, the quietest, with the bed’s head to the top wall, which faces nothing; the wardrobe stands on the party wall between the bed and the neighbour, and the bathroom sits between the bedroom and the lift as a buffer of water and tile. The living room takes the street, with a bookcase on the party wall, a rug on the floor and heavy curtains at the window; the bedroom door closes to the floor and a strip on it stops what comes under. Nothing that hums, drips or ticks stands in the bedroom. The tradition’s still room and the acoustician’s are the same room, at the far end from every source.

The plan is the tradition’s gradient with the sources marked. The bedroom is at the far end from the door and from the street, in the corner that faces nothing, with the bed’s head to a wall that has nothing behind it; the bedroom page wants it there for the sake of yin and the acoustician for the sake of distance and mass. The wardrobe stands on the party wall between the bed and the neighbour’s television, a metre of clothes being the best sound absorber a flat owns; the bathroom sits between the bedroom and the lift as a buffer of tile and water. The living room takes the street, with a bookcase on the party wall, a rug on the floor and heavy curtains that close over the window, all of which the tradition wants for other reasons, the sofa’s wall, the soft room, the yin evening, and all of which absorb. The bedroom door closes to the floor with a strip on it, and nothing hums in the room.

Design observation · Mass, distance, absorption, and the gap

Sound is stopped by mass and distance and softened by absorption, and it leaks through gaps. A brick wall drops it by about forty-five decibels, a stud partition by thirty, a closed double-glazed window by thirty and an open one by nothing; a curtain takes a few decibels off the reflection and none off what comes through the glass; a gap under a door lets through most of what the door stopped. The rules that follow are the tradition’s in other words. Put the sleeping at the far end and the sources near the door, which is the gradient; put the soft things in the still room and the hard things in the yang one; close what can be closed at night, the window, the curtain, the door; and take out what hums, drips or ticks, because at twenty-five decibels a fridge in the room is the loudest thing in it.

Water, and where it goes

The tradition likes moving water in front of a house and dislikes it in a bedroom, and the scale explains both. A fountain in a courtyard or beside a door is a sound that covers others, the traffic behind it and the neighbour’s voice, at a level, fifty or so a few metres off, that the ear reads as pleasant; the same fountain in a bedroom is sixty-five at the pillow and a thing the body listens to all night. Alexander’s pattern for still water and his pattern for the sound of a fountain in a public place make the same distinction from the other side. The water features guide gives the tradition’s placements; the rule for sound is that water belongs where people are awake.

Checklist

The bedroom at the far end from the street, the lift and the front door, in the corner that faces nothing
The bed’s head to a wall with nothing behind it; the wardrobe on the party wall; the bathroom as a buffer
Nothing in the bedroom that hums, drips, ticks or rings; the fountain and the chime elsewhere
Soft things in the still rooms: rug, curtains that close, books on the party wall
The bedroom door closed to the floor at night; the window closed on the street side
Water outside or at the entrance, where people are awake; bells at the gate
Thirty decibels at the pillow, forty outside the window at night, as the guidelines ask; a phone app will measure it