PVC-U Double Branch Fittings
A double branch takes two incoming connections at the same level on opposite sides of the stack. It is the standard fitting for back-to-back bathrooms, which is how most residential towers in the region are planned.
Also searched as: double branch, cross, double Y, back to back branch, double tee
Back-to-back planning
Where two apartments share a wet wall, both WCs connect to the same stack at the same floor level. The double branch makes that connection in one fitting rather than two separate branches stacked vertically, which saves floor-to-floor height in the duct.
Cross-flow
Because two flows enter opposite each other, a double branch is the fitting most exposed to cross-flow — discharge from one appliance entering the other. Use the correct pattern with the offset inlets and observe the branch connection zone in the Technical Manual. Do not substitute two opposed single branches at the same level.
Sizes
Available in 110mm and 160mm as standard, with unequal patterns such as 200 × 160mm for main collection runs. Both 87.5° and 45° angles are produced.