ASTM F877
Standard Specification for Crosslinked Polyethylene (PEX) Plastic Hot- and Cold-Water Distribution Systems
Last updated: March 26, 2026
Contents
Overview
ASTM F877 covers crosslinked polyethylene (PEX) tubing and fittings used in hot and cold water distribution systems. PEX is a flexible plastic piping material that has revolutionized plumbing installations through its resistance to scale and chlorine, flexibility for fewer connections, and ability to expand without bursting in freezing conditions. The standard covers PEX-a, PEX-b, and PEX-c manufacturing methods.
Performance Requirements
- Pressure ratings: 160 psi at 73°F, 100 psi at 180°F
- Temperature resistance: Continuous operation up to 200°F
- Chlorine resistance: 4.3 ppm chlorine at 140°F for 50-year life
- UV resistance requirements for outdoor storage
- Burst pressure testing and long-term hydrostatic strength
Installation Advantages
PEX flexibility allows for continuous runs with fewer fittings, reducing potential leak points. The material can be snaked through walls and around obstacles, minimizing demolition during retrofits. Home-run manifold systems eliminate hidden joints in walls. PEX expansion during freezing provides freeze-break resistance superior to rigid piping, though it's not freeze-proof and must still be protected from sustained freezing.
Code Compliance and Limitations
ASTM F877 is referenced in major plumbing codes including the IPC and UPC. However, PEX has limitations: it cannot be used outdoors exposed to UV light, requires protection from physical damage, and isn't suitable for compressed air systems. Some jurisdictions restrict PEX use in certain applications. Proper support spacing (32" for 1/2" horizontal runs) and expansion compensation must be provided per manufacturer instructions.
Compatible Fittings and Connection Methods
F877 covers the complete PEX system, not just tubing. The fitting connection method you use determines which additional ASTM standard applies. Not every fitting type works with every PEX type (a, b, or c), so matching is important.
| Method | ASTM Standard | PEX Types | How It Works |
|---|---|---|---|
| Crimp (copper ring) | ASTM F1807 | PEX-a, PEX-b, PEX-c | Copper crimp ring compressed over a barbed brass fitting. Most common method. Requires a crimp tool and go/no-go gauge. |
| Expansion (cold expansion) | ASTM F1960 | PEX-a only | Tubing is expanded, fitting inserted, tubing shrinks back to form the seal. Strongest joint. Requires an expansion tool. |
| Push-fit (push-to-connect) | ASTM F2159 | PEX-a, PEX-b, PEX-c | Tubing pushes into fitting with internal teeth and O-ring. No tools needed. Good for repairs and tight spaces. SharkBite is the common brand. |
| Press (ProPress style) | ASTM F2080 | PEX-a, PEX-b | Stainless steel sleeve pressed over fitting with a powered press tool. Fast for commercial runs. Requires press tool with PEX jaws. |
| Clamp (stainless steel) | ASTM F2098 | PEX-a, PEX-b, PEX-c | Stainless steel cinch clamp over barbed fitting. Similar to crimp but uses a ratchet clamp tool instead of a crimp ring. |
PEX-a vs PEX-b matters here. Expansion fittings (F1960) only work with PEX-a because PEX-b does not have enough shape memory to shrink back and form a seal. Crimp, clamp, and push-fit work with all three PEX types. If you are specifying a system, confirm the tubing type before choosing fittings.