The side alley is out of bounds; the back alley is in bounds or good. The serve must carry past the short service line, which is 6.5 feet (about 2 m) from the net, and must not carry beyond the back boundary line. The lines are considered part of the court and in bounds.
On a regulation badminton court, the outer sidelines will run the full 13.41m /44.00ft length of the court. The outer sidelines are marked 5.18m (17.00ft) apart and run parallel to one another. Any shot that lands inside the doubles sideline is considered “in” or valid for doubles matches.
The outer sidelines are sometimes referred to as “outer tramlines” or “doubles sidelines”. On a regulation badminton court, the outer sidelines will run the full 13.41m /44.00ft length of the court. The outer sidelines are marked 5.18m (17.00ft) apart and run parallel to one another.
Badminton Rules: Doubles – what's in and what's out? During the main part of a badminton doubles rally, every part of the court is in. However, the serve must fall into the 'short and ' area diagonally opposite the server. The side tramlines are in, but the rear tramlines are out during the serve.
- A legal doubles serve would land in the area bounded by the center line, the doubles long service line, the doubles side line and the short service line (short and wide). - Once the serve is made in doubles, the court area is bounded by the doubles sideline and the back boundary line.
The lines marking out the court are easily distinguishable and coloured white or yellow. The lines are 40mm wide. A court may be marked out for singles only. The back boundary lines also become the long service lines and the posts or the strips of material representing them are placed on the side lines.
In singles the court is thinner, with the wide, outside 'tramlines' out of bounds. In doubles the court is full width and these tramlines are now 'in'. During service in doubles, the court is short, with the rear 'tramlines'at the back of the court, being out of bounds until the serve is returned.
A singles service court is a box made from four lines: The centre line. A singles side line (inside side line) The front service line. The back line (the outside one, all the way at the back)
Games can be played as a doubles format with four players, or singles between two players. The court boundaries for doubles and singles are different. In singles the court is thinner, with the wide, outside 'tramlines' out of bounds. In doubles the court is full width and these tramlines are now 'in'.
This means if the ball touches the line, it is still in play. The ball must wholly cross the boundary line to be considered out of play.