Pipes & Fittings Buying Guides

Choosing the right pipe material and fitting type is critical for code compliance, longevity, and water quality. Your selection depends on the application (supply vs drain), local building codes, water chemistry, and installation skill level.

We have 5 buying guides covering pipes & fittings topics.

All Pipes & Fittings Buying Guides 5

Drain Pipe Materials: PVC vs ABS vs Cast Iron

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Drain pipes carry wastewater by gravity -- no pressure. The three materials used in residential DWV (drain, waste, vent) systems are PVC, ABS, and cast iron. PVC is the current standard. ABS is common in western states. Cast iron is found in older homes and is quieter but heavy and eventually corrodes.

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Key tips:PVC is the standard choice for new residential DWV work in most areas.If noise matters (drains running through bedroom walls), consider cast iron for those specific runs.Never mix PVC and ABS with solvent cement. Use a mechanical transition coupling.Schedule 40 is standard. Schedule 20 (thin-wall) is for non-structural drain applications only.

Bottom line: PVC for new work. Replace cast iron when walls are open during renovations. ABS is equivalent to PVC where code allows. Use cast iron selectively for noise-sensitive runs.

Fitting Types & Connection Methods

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Every pipe connection is a potential leak point. The connection method you choose affects reliability, ease of installation, cost, and whether you can DIY the work. Push-fit fittings need no tools. Soldering requires skill and a torch. Crimp and expansion need specific tools. Threaded connections are the oldest and most universal.

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Key tips:Push-fit for repairs and tight spaces. Soldered or crimped for new full-line installations.Always deburr pipe ends before any connection method. Burrs cause leaks.Keep spare push-fit caps and couplings for emergency repairs.PEX expansion connections are the most forgiving -- the pipe self-heals minor misalignment.

Bottom line: Push-fit for DIY repairs and transitions. Solder for copper new work. Crimp or expansion for PEX new work. Each method is reliable when done correctly -- the key is proper preparation.

PEX vs Copper Pipes: Complete Comparison

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PEX has overtaken copper as the most-installed residential water supply pipe in new construction. It costs 60-70% less in materials, installs 3-4x faster, and resists freezing better than copper. But copper still has advantages: it handles UV exposure, does not need special fittings at every joint, and has a 50+ year track record. The right choice depends on your project scope, budget, local code, and whether the pipes will be exposed to sunlight. Here is the full comparison with real numbers.

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Key tips:Check your local plumbing code before choosing. Some jurisdictions require copper for specific applications (like the water heater connection or the first few feet from the meter). Most accept PEX for all interior supply lines.PEX comes in three types: PEX-A (most flexible, expansion fittings), PEX-B (most common, crimp fittings), and PEX-C (least common). All three are acceptable for residential supply lines. PEX-A costs 20-30% more but is easier to work with.Copper scrap has value. If you repipe from copper to PEX, save the old copper and sell it to a scrap metal dealer. A full house of 1/2-inch and 3/4-inch copper is worth $100-$400 in scrap.For a repipe, PEX manifold systems run dedicated lines from a central manifold to each fixture. This eliminates tee fittings in walls, reduces leak points, and allows individual fixture shut-offs from the manifold.

Bottom line: PEX is the better choice for most residential projects: 60-70% cheaper, easier to install, freeze-resistant, and code-approved nearly everywhere. Copper is the better choice for exposed outdoor runs, water heater connections, and situations where the 50-year track record matters. For a full house repipe, PEX saves $3,000-$7,000 vs copper with equivalent performance.

Pipe Sizing & Flow Rates

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Undersized pipes mean low pressure, slow filling, and poor shower performance. Oversized pipes waste material and money. Getting the sizing right ensures every fixture performs well, even when multiple fixtures run simultaneously. This guide covers supply and drain pipe sizing for residential applications.

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Key tips:When in doubt, size up. A 3/4 inch line costs marginally more than 1/2 inch but delivers significantly more flow.Long runs need larger pipe. Friction loss increases with distance -- a 50-foot 1/2 inch run loses more pressure than a 10-foot run.Home-run PEX manifold systems deliver better pressure to each fixture because each line is dedicated.If adding a bathroom or fixture, verify the existing main line can handle the additional demand.

Bottom line: 3/4 inch supply mains, 1/2 inch branches, 2 inch drains for kitchens and baths, 3 inch for toilets. Size up for long runs. The cost difference is small but the performance difference is significant.

Supply Pipe Materials: Copper vs PEX vs CPVC

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Copper, PEX, and CPVC are the three materials used for residential water supply lines. Each has strengths and tradeoffs in cost, durability, installation difficulty, and longevity. PEX has largely replaced copper in new construction due to lower cost and easier installation, but copper remains the premium choice.

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Key tips:PEX is the best choice for most DIY repiping projects -- flexible, forgiving, and affordable.Copper is worth the premium if longevity and resale value matter most.Use push-fit fittings to transition between pipe types during repairs.Check local code -- some areas restrict CPVC or require specific PEX connection methods.

Bottom line: PEX is the best value for most residential projects. Copper is the premium, long-term choice. CPVC is the budget option but is declining in popularity. Check local code before choosing.

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Frequently Asked Questions

How many buying guides are there for pipes & fittings?

We cover 5 buying guides for pipes & fittings: Drain Pipe Materials: PVC vs ABS vs Cast Iron, Fitting Types & Connection Methods, PEX vs Copper Pipes: Complete Comparison, Pipe Sizing & Flow Rates, Supply Pipe Materials: Copper vs PEX vs CPVC.

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