This is the #1 reason for **low shower pressure from roof tank** - and fix costs just 1 extra pipe! **LEFT - WRONG - No Vent Pipe = Slow Flow ❌** Tank on roof, pipe goes directly down to shower. No air entry. What happens: - Water tries to go down, but air gets trapped inside pipe - like putting finger on top of a straw, water won’t fall. - Pipe creates air lock / vacuum. Water has to fight air to come out. - Result: Weak, slow shower, even though tank is full. **RIGHT - CORRECT - Extra Vent Pipe = Strong Flow ✅** One extra vertical pipe added, higher than tank top, open to air. See labels: - **Extra Vent Pipe** - Connects to main down pipe - **Air Escape** - Blue arrows UP from tank and vent How it fixes: - When water goes down to shower, air from this vent pipe goes IN behind water, pushing it down. - No air lock. Water flows freely with gravity. - Also, air trapped in tank escapes through small pipe on tank top. Result: Same tank, same height, but **3x stronger flow**. **Installation Rules:** 1. Vent pipe diameter = same as main pipe (1 inch) 2. Vent height = 1 foot higher than tank lid 3. Top of vent = open, with U-bend to stop dust/birds 4. Connect vent as close to tank down-takeoff as possible Cost: 10 feet pipe + elbow = very cheap, but shower feels like pressure pump! Try this before buying a pump motor. #plumbing #waterpressure #watertank