The minimum area of vertical reinforcement in the wall should be 0.4% of the
gross cross sectional area of the concrete and should be equally divided between
the two faces of the wall.The maximum area of vertical reinforcement should not
exceed 4% of the gross cross sectional area of the concrete. Horizontal
reinforcement equal to not less than half the area of vertical reinforcement
should be provided between the vertical reinforcement and the wall surface on
both faces.The spacing of the vertical bars should not exceed the lesser of
300mm or twice the wall thickness. The spacing of horizontal bars should not
exceed 300mm and the diameter should not be less than one-quarter of the
vertical bars. If the vertical reinforcement exceeds 2% of the gross
cross-sectional area of the concrete then links should be provided in accordance
with EC2 – clause 5.5.6.