Fixture Units to Pipe Size: Horizontal Branch ≤ 50 DFU
Specific conversion page with reference context, calculator, and nearby values.
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Horizontal Branch ≤ 50 DFU converts to
4 in
Use this as a quick reference for Fixture Units to Pipe Size.
Value Details
Input: Horizontal Branch ≤ 50 DFU
Output: 4 in
Browse all reference values for Fixture Units to Pipe Size
systemLabel: Horizontal Branch | maxDfu: 50 | minSlopeInPerFt: 0.125
Fixture Units to Pipe Size Lookup
Select system type and fixture-unit load to estimate minimum drainage pipe size.
Recommended Pipe Size
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Nearby Reference Values
| System | Max DFU | Pipe Size | Min Slope (in/ft) |
|---|---|---|---|
| Horizontal Branch | 3 | 1-1/2 in | 0.25 |
| Horizontal Branch | 8 | 2 in | 0.25 |
| Horizontal Branch | 24 | 3 in | 0.125 |
| Horizontal Branch | 50 | 4 in | 0.125 |
| Horizontal Branch | 180 | 6 in | 0.125 |
| Horizontal Branch | 390 | 8 in | 0.125 |
| Building Drain | 2 | 1-1/2 in | 0.25 |
| Building Drain | 6 | 2 in | 0.25 |
| Building Drain | 20 | 3 in | 0.125 |
Frequently Asked Questions
Common questions about Fixture Units to Pipe Size, formulas, and expected usage.
What are drainage fixture units (DFU)?
DFU is a plumbing design unit that represents probable drainage load from fixtures and helps size drainage piping.
Why are branch and building drain tables different?
Different parts of the drainage system can have different loading and sizing rules, so lookup limits vary by system type.
Does this replace full plumbing code tables?
No. Use this as a quick planning reference; final design must follow adopted local plumbing code and authority requirements.
Why include minimum slope with pipe size?
Adequate slope is essential for gravity drainage performance and is typically tied to pipe size and code requirements.
Methodology and Review
This page is generated from the same conversion definition used by the main calculator page, which keeps the calculator, reference table rows, and FAQ schema aligned.
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Use this page as a fast lookup reference, then confirm final project values using applicable standards and manufacturer documentation.