What Type of Pipes Do I Have? Read the Wall Before You Call

• Water heater connections. The cold inlet and hot outlet show the supply material at eye level, often with a heater-swap transition: old material one side of a fitting, new the other. The Kitec settlement FAQ names the hot water tank and the mechanical room among the best places to look.
• Under sinks, then a long run. Where the pipe exits the wall behind the stop valve; the Kitec FAQ lists kitchen sinks and bathroom vanities, and the polybutylene settlement notice adds attics, crawl spaces and water heater closets. Then one long exposed run, for the joints, color changes and print a stub cannot show.
• The meter entry, where this guide stops. The pipe through the outside wall to the meter is the service line (the Philadelphia Water Department puts the meter usually in the basement by the wall closest to the street; the City of Troy, NY tests that pipe before the shutoff valve and meter). Lead belongs there, on the Water Lines page.

• Galvanized steel. Dark gray to silver-gray metal in rigid sections with threaded, screw-together joints; a magnet sticks and a scratch stays dull gray (City of Troy, NY; North Dakota DEQ). East Bay Municipal Utility District says it was commonly used before the 1960s in its area, and that once the zinc is gone the iron rusts and the pipe leaks. The Galvanized Pipe Replacement page carries the verdict.
• Copper. Penny colored when new, brown with age, sometimes with green or dark brown tarnish; joints are soldered; a magnet does not stick (Village of Allouez, WI; City of Troy, NY). Hard tube is printed in the Copper Development Association's color code: Type K green, Type L blue, Type M red, all ASTM B 88. Condition decides copper's future; the repipe-or-repair guide reads it.
• Polybutylene. Non-rigid, sometimes curved, usually gray plastic with acetal plastic or metal insert fittings, as the Cox v. Shell settlement notice describes it; the notice puts it in an estimated six million homes between January 1, 1978 and July 31, 1995. ASTM withdrew its standard, D3309, in 2010 with no replacement. The Polybutylene Pipe Replacement page carries the verdict.
• Kitec. Blue pipe for cold and orange for hot, with Kitec or KTC on visible fittings; CSA B137.9/10 or ASTM F1974 marks can also point to it, per the settlement FAQ. The FAQ names white residue on fittings and blackening or bulging pipe as the first failure signs, and states a claims deadline of January 9, 2020. The Kitec Pipe Replacement page carries the verdict.
• PEX. Flexible tubing printed with ASTM F876, size, SDR and pressure rating (Plastic Pipe and Fittings Association handbook). Red hot and blue cold is a manufacturer convention (Uponor sells it that way), not a rule. The Plastics Pipe Institute dates ASTM F876 to 1984 and its first model-code listing to the 1993 BOCA code.
• CPVC. Rigid plastic, tan with a yellow stripe in the FlowGuard Gold product Cresline lists, made to ASTM D2846. FlowGuard Gold's history dates the first CPVC-plumbed house to the NAHB Research House in Lansing, Michigan, in 1959.

• Cast iron. The heavy metal stack. The Cast Iron Soil Pipe Institute handbook classifies it as hub and spigot, sealed with a rubber compression gasket or molten lead and oakum, or hubless, joined with stainless No-Hub couplings. Indoors the stack belongs to the Drain / Waste / Vent Pipe Repair & Replacement page; the buried run, after the camera, to Cast Iron Sewer Pipe Repair.
• ABS and PVC. Charlotte Pipe's product guide: ABS DWV pipe and fittings are black, PVC DWV pipe and fittings are white, and solid-wall PVC is often dual marked ASTM D 1785 and D 2665.
• What indoors cannot show. The buried lateral is out of sight; Orangeburg or clay cannot be read from a basement. Sewer Camera Inspection first, then the Orangeburg Sewer Pipe Replacement or cast iron page the footage names.

One word per material, with the material page as the authority: galvanized, replace. Polybutylene, replace. Kitec, replace. Copper, fine. PEX, fine. CPVC, fine. Cast iron drain, watch. ABS and PVC drain, fine. For service life, InterNACHI's estimated life expectancy chart lists copper water lines at 70 years (and a second copper water line row at 50), PEX at 40, ABS and PVC waste pipe at 50 to 80 and above-ground cast iron waste pipe at 60, notes that life varies, and has no row for galvanized or polybutylene supply. Build era is a candidate list; the pipe confirms.

The ASHI Standard of Practice (2026) has the home inspector describe the predominant type and material of visible and accessible supply and drain, waste and vent piping, excludes concealed conditions, and does not require a determination of whether polybutylene or similar plastic piping is present. The Pre-Purchase Plumbing Inspection is the every-visible-point version built for the contingency window.

• Galvanized Pipe Replacement
• Polybutylene Pipe Replacement
• Kitec Pipe Replacement
• Whole-House Repiping
• Lead Service Line Replacement
• Cast Iron Sewer Pipe Repair
• Orangeburg Sewer Pipe Replacement
• Pre-Purchase Plumbing Inspection

• Repair, Replace the Run, or Repipe? The Escalation Ladder
• Whole-House Repipe Cost: What Sets the Number
• Discolored Tap Water: Read the Color, Find the Cause
• Sewer Line: Repair or Replace? Let the Footage Decide