The thickness of PVC sports flooring suitable for badminton courts typically ranges from 4.5mm to 8mm. The choice of thickness depends on various factors including the type of subfloor, level of shock absorption required, and budget constraints. 

Subfloor Condition: If the subfloor is uneven or in poor condition, thicker PVC flooring may be needed to provide adequate support and cushioning for players. Thicker flooring can help to level out minor irregularities in the subfloor, ensuring a smooth and consistent playing surface.

Shock Absorption: Thicker PVC flooring typically offers better shock absorption properties, which can help reduce the risk of injuries by cushioning players' joints and muscles during intense gameplay. This is particularly important for sports like badminton, where players engage in rapid movements and sudden changes in direction.

Budget: Thicker PVC flooring tends to be more expensive than thinner options, so budget considerations may influence the choice of thickness. However, investing in higher-quality, thicker flooring can lead to long-term cost savings by reducing the need for frequent replacements and repairs.

Performance Requirements: Consider the level of play and performance requirements for the badminton court. Thicker flooring may be preferred for professional or competitive venues where players demand optimal playing conditions and performance consistency.

In summary, a thickness of around 6mm is generally suitable for most badminton courts, providing a good balance of support, shock absorption, and performance.