PEX Piping
Updated February 24, 2026
Cross-linked polyethylene tubing that is flexible, freeze-resistant, and easy to install. The most popular choice for modern residential plumbing. Typical price range: $0.40 – $1.50/ft. Best for: Residential repiping, new construction.
Overview
PEX (cross-linked polyethylene) has largely replaced copper for new residential water supply installations. Flexible, freeze-resistant, corrosion-proof, and dramatically cheaper than copper. Runs in long continuous lengths from a manifold to each fixture with fewer fittings and no joints inside walls. Three types: PEX-A (most flexible, expands for connections), PEX-B (stiffer, crimp connections), and PEX-C (least common). Red for hot, blue for cold, white for either. Cannot be used outdoors -- UV degrades it.
How to Choose PEX Piping
PEX Piping are best suited for residential repiping, new construction. They typically cost $0.40 – $1.50/ft, so plan your budget accordingly. Sizing is important — 3/4 inch for main trunk lines, 1/2 inch for branches to individual fixtures, 3/8 inch for short runs to single fixtures.... Key advantages include flexible and freeze resistant.
Pros & Cons
- Flexible
- Freeze resistant
- Easy installation
- Corrosion proof
- Affordable
- Not UV resistant
- Cannot be used outdoors
- Some fittings restrict flow
Key Features
- Flexible -- bends around corners without elbows, reducing fitting count
- Freeze-resistant -- expands up to 3x pipe diameter before bursting
- Corrosion-proof -- no pitting, scaling, or galvanic corrosion
- Runs in continuous lengths (up to 1000 feet per roll) for fewer joints
- Manifold systems allow individual fixture shut-offs from a central location
Top Brands for PEX Piping
Sizing & Selection
3/4 inch for main trunk lines, 1/2 inch for branches to individual fixtures, 3/8 inch for short runs to single fixtures. Home-run (manifold) systems use 1/2 inch or 3/8 inch from the manifold to each fixture. Trunk-and-branch systems use 3/4 inch mains with 1/2 inch branches. Home-run uses more pipe but provides better pressure and individual shut-off capability.
Installation
PEX-A: expansion connections (Uponor/Wirsbo style). Expand the pipe end and ring, insert the fitting, the pipe shrinks back for a tight seal. PEX-B: crimp rings with a crimp tool, or cinch clamps with a cinch tool. Push-fit fittings (SharkBite) work on all PEX types. Support with hangers every 32 inches on horizontal runs. PEX cannot be directly connected to a water heater -- use 18 inches of copper or a braided connector at the heater.
Maintenance
- PEX is essentially maintenance-free inside walls. No corrosion, no scaling.
- Protect from UV exposure -- even indirect sunlight degrades PEX over time. Cover any exposed runs.
- Inspect accessible fittings annually for signs of dripping, especially crimp connections.
- PEX fittings slightly reduce the internal diameter at each connection point. Minimize fittings on long runs to maintain flow.
Buying Tips
- PEX-A is best for DIY -- expansion fittings are the most forgiving and the pipe is most flexible.
- PEX-B with crimp rings is the most common professional choice -- lower material cost, proven reliability.
- Buy a PEX manifold system if doing a whole-house install. Individual fixture shut-offs are incredibly convenient.
- Viega, Uponor, and SharkBite are the most trusted PEX brands. Avoid unknown brands -- fitting quality matters.
- Color code your runs (red hot, blue cold) even though white PEX works for both. Future you will thank present you.
Frequently Asked Questions
What are the advantages of pex piping?
Flexible Freeze resistant Easy installation Corrosion proof Affordable
What are the disadvantages of pex piping?
Not UV resistant Cannot be used outdoors Some fittings restrict flow
Who should buy pex piping?
PEX Piping are best for: Residential repiping, new construction.
How are pex piping installed?
PEX-A: expansion connections (Uponor/Wirsbo style). Expand the pipe end and ring, insert the fitting, the pipe shrinks back for a tight seal. PEX-B: crimp rings with a crimp tool, or cinch clamps with a cinch tool. Push-fit fittings (SharkBite) work on all PEX types. Support with hangers every 32 inches on horizontal runs. PEX cannot be directly connected to a water heater -- use 18 inches of copper or a braided connector at the heater.
How do I choose the right size for pex piping?
3/4 inch for main trunk lines, 1/2 inch for branches to individual fixtures, 3/8 inch for short runs to single fixtures. Home-run (manifold) systems use 1/2 inch or 3/8 inch from the manifold to each fixture. Trunk-and-branch systems use 3/4 inch mains with 1/2 inch branches. Home-run uses more pipe but provides better pressure and individual shut-off capability.
What are the best brands for pex piping?
Top brands for pex piping include Apollo, BrassCraft, Canplas, Charlotte Pipe. Each offers different price tiers and product lines.
How do I maintain pex piping?
Key maintenance tips: PEX is essentially maintenance-free inside walls. No corrosion, no scaling.. Protect from UV exposure -- even indirect sunlight degrades PEX over time. Cover any exposed runs.. Inspect accessible fittings annually for signs of dripping, especially crimp connections..