A practical guide from the team at Puranmal Sons & Ceramix Syndicate.
Each tap, shower and appliance needs a certain flow. More fixtures on a line means a larger pipe to keep pressure steady. As a rough guide, individual fixture branches are often 15 mm (1/2"), with 20–25 mm for lines feeding several fixtures.
The incoming main and risers are sized larger — commonly 25 mm and up — because they carry the combined demand. Undersizing the main causes pressure to drop when several taps run together.
Hot water lines use CPVC and are sized like cold lines, but keep runs as short as practical to reduce heat loss and waiting time.
For a whole house, it's worth having the sizes specified against the layout. Share your plan and fixture list and we'll help you work out sizes and quantities.
Share your list or BOQ and we'll call back with pricing and availability, usually the same working day.
