What is building and breaking the wall in Mahjong (Riichi)?

Verdict

Tiles are shuffled face-down; each player builds a wall seventeen tiles long and two tiles high, and the four walls are pushed together into a square (2.4); East rolls two dice and counts that number of players counter-clockwise, starting with themselves; that player's wall is broken, counting fr...

Why people argue about this

People often assume that breaking the wall happens immediately after it's built, without considering the East player's roll first. This leads to misunderstandings about who actually breaks their wall and when, causing confusion in game play.

Send this to your friend — argument over.

3. Setup

Seats and Winds

Four players, each associated with a seat wind. East is the starting player; South sits at East's right, West across from East, North at East's left (2.1)
The counter-clockwise order east-south-west-north does not correspond to compass directions (2.1)
Over a full game each player is East at least twice (2.1)
East is the round wind when the game begins; when the starting East becomes East again, the south round begins and a wind marker is flipped (2.2)
Seats are decided by drawing lots with one tile of each wind, unless a tournament schedule fixes them. The player who shuffled picks last, and at least three players must be present for the draw (2.3)

Building and Breaking the Wall

Tiles are shuffled face-down; each player builds a wall seventeen tiles long and two tiles high, and the four walls are pushed together into a square (2.4)
East rolls two dice and counts that number of players counter-clockwise, starting with themselves; that player's wall is broken, counting from their right the same number of tile stacks (2.5)

The Dead Wall and Dora

The first seven tile stacks counter-clockwise from the break form the dead wall — fourteen tiles (2.6)
The four tiles closest to the break are replacement tiles; the next ten are the dora indicator, the kan dora indicators and the ura dora indicators (2.6)
The dora indicator is revealed by counting three tile stacks into the dead wall from the break and turning the top tile over (2.7)
The dora is the next tile after the indicator: for a suit tile the following number, with 9 pointing to 1; for dragons red→white→green→red; for winds east→south→west→north→east (2.7)

The Deal

East draws the first four tiles after the break, then South, West and North take four each, repeating until every player holds twelve tiles (2.8)
East then takes two tiles (the top tiles of the first and third stacks) and the others one each, so East starts with fourteen tiles and everyone else with thirteen (2.8)
Tiles are taken clockwise even though turns proceed counter-clockwise (2.8)
The dice are placed at East's right where possible, so it is always clear who is East (2.8)

3. Setup

Seats and Winds

Four players, each associated with a seat wind. East is the starting player; South sits at East's right, West across from East, North at East's left (2.1)

The counter-clockwise order east-south-west-north does not correspond to compass directions (2.1)

Over a full game each player is East at least twice (2.1)

East is the round wind when the game begins; when the starting East becomes East again, the south round begins and a wind marker is flipped (2.2)

Seats are decided by drawing lots with one tile of each wind, unless a tournament schedule fixes them. The player who shuffled picks last, and at least three players must be present for the draw (2.3)

Building and Breaking the Wall

Tiles are shuffled face-down; each player builds a wall seventeen tiles long and two tiles high, and the four walls are pushed together into a square (2.4)

East rolls two dice and counts that number of players counter-clockwise, starting with themselves; that player's wall is broken, counting from their right the same number of tile stacks (2.5)

The Dead Wall and Dora

The first seven tile stacks counter-clockwise from the break form the dead wall — fourteen tiles (2.6)

The four tiles closest to the break are replacement tiles; the next ten are the dora indicator, the kan dora indicators and the ura dora indicators (2.6)

The dora indicator is revealed by counting three tile stacks into the dead wall from the break and turning the top tile over (2.7)

The dora is the next tile after the indicator: for a suit tile the following number, with 9 pointing to 1; for dragons red→white→green→red; for winds east→south→west→north→east (2.7)

The Deal

East draws the first four tiles after the break, then South, West and North take four each, repeating until every player holds twelve tiles (2.8)

East then takes two tiles (the top tiles of the first and third stacks) and the others one each, so East starts with fourteen tiles and everyone else with thirteen (2.8)

Tiles are taken clockwise even though turns proceed counter-clockwise (2.8)

The dice are placed at East's right where possible, so it is always clear who is East (2.8)

Building and Breaking the Wall