Plumbing Decision
PEX-A vs. PEX-B
Hidden inside the walls — pick once.
Spec
PEX-A
PEX-B
Typical 2026 cost
$0.55–$1.20 per linear ft
$0.40–$0.85 per linear ft
Lifespan
50+ years
50+ years
Performance
Most flexible; expansion-fit (Uponor) connections
Stiffer; crimp or clamp connections
The Verdict
PEX-A is the premium pick for tight retrofits and freeze-resistance. PEX-B wins on cost for new construction with straight runs.
Key Facts
- PEX-A can recover from one freeze cycle without rupture
- PEX-A expansion fittings have larger ID than PEX-B crimp
- PEX-B is more rigid and uses cheaper PEX-B fittings
- Major brands: Uponor (PEX-A), SharkBite/Apollo (PEX-B)
Which Should You Pick?
Pick PEX-A if you have:
- retrofit with tight bend radii
- cold climates with freeze-risk runs
- fewer fittings desired (longer continuous runs)
Pick PEX-B if you have:
- new construction with straight chases
- budget-driven re-pipes
- DIY installs (more familiar fitting types)
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