Section 3: Playing Area
3.1 Sheet Dimensions
Under Rule R1(a), the length of the ice sheet from the inside edges of the back boards is a minimum of 45.720 m (150 ft), and the width from the inside edges of the side lines is a maximum of 4.750 m (15 ft 7 in). If an existing facility cannot accommodate these measurements, the length may be reduced to a minimum of 44.501 m (146 ft) and the width to a minimum of 4.420 m (14 ft 6 in).
3.2 Key Lines and Markings
Rule R1(b) sets out the markings at each end of the sheet, drawn from side line to side line:
- Tee line: Maximum width 13 mm (1/2 in), placed so its centre is 17.375 m (57 ft) from the middle of the sheet.
- Back line: Maximum width 13 mm (1/2 in), with its outside edge 1.829 m (6 ft) from the centre of the tee line. A stone that completely crosses the outside edge of the back line at the playing end is removed from play immediately (R2(g)).
- Hog line: Width 102 mm (4 in), with its inside edge 6.401 m (21 ft) from the centre of the tee line. The delivering player must clearly release the stone before it reaches the near (delivery-end) hog line (R5(e)), and a stone must come to rest completely beyond the inside edge of the hog line at the playing end to remain in play, unless it strikes another stone already in play (R2(f)).
- Centre line: Maximum width 13 mm (1/2 in), joining the midpoints of the tee lines and extending 3.658 m (12 ft) beyond the centre of each tee line.
- Hack line: Length 457 mm (1 ft 6 in), maximum width 13 mm (1/2 in), placed parallel to the tee line at each end of the centre line.
- Courtesy line: Length 152 mm (6 in), maximum width 13 mm (1/2 in), placed 1.219 m (4 ft) outside and parallel to the hog lines on each side of the sheet.
3.3 The House (Target)
Rule R1(d) provides that a centre hole (tee) is placed at the intersection of each tee line and centre line. With the tee as centre, there are four concentric circles at each end of the sheet: the outer circle has a radius of 1.829 m (6 ft, the 12-foot ring), the next a radius of 1.219 m (4 ft, the 8-foot ring), the next a radius of 610 mm (2 ft, the 4-foot ring), and the innermost circle a minimum radius of 152 mm (6 in, the button). A stone may be measured only visually until the last stone of the end has come to rest, except to determine whether a stone is in play or, before the second through fifth stones of an end, whether a stone is in the Free Guard Zone (R2(i)).
3.4 Ice Preparation
The ice surface is maintained at approximately −5°C (23°F). After being levelled flat, the ice is pebbled — fine water droplets are sprayed onto the surface and allowed to freeze, creating a textured finish of small bumps. This pebble reduces the contact area between stone and ice, lowering friction and enabling the stone to curl. The pebble is nipped (shaved level) before play to ensure consistency.
3.5 Free Guard Zone
Under Rule R6(a), a stone that comes to rest between the tee line and the hog line at the playing end, excluding the house, is within the Free Guard Zone (FGZ). Stones resting in this zone are protected under the FGZ rule until the delivery of the sixth stone of the end (R6(b); see Section 5). This rule does not apply to Wheelchair Curling or Mixed Doubles competitions (R6(c)).