Whole-house repiping in Saint Paul, MN

Galvanized steel pipe has a zinc coating meant to slow rust. Over decades the zinc wears away and the steel starts to corrode inside. Rust and mineral deposits build up on the walls, shrinking a half inch pipe down to a pencil sized hole. You feel it as weak flow and see it as discolored water. The outside can look fine while the inside is nearly closed.

Joints are the weak points. Every threaded connection removes metal from the pipe wall, so leaks tend to show up there first. Repairing one leak often disturbs rust nearby and causes another. Galvanized lines can also hold lead in their scale if they were ever downstream of a lead service line, which is one more reason to replace them rather than patch.

Both are solid choices, and we install both. Copper is rigid, long lasting and handles high heat, and many homeowners like how it looks in an unfinished basement. It costs more in materials and takes more labor to route through finished walls. PEX is flexible plastic tubing that bends around obstacles, needs fewer fittings, and is less likely to burst if it freezes. It usually means fewer wall openings.

Many repipes use both. We might run copper near the water heater and in the basement, where it's exposed, then switch to PEX for the runs that snake up through walls to bathrooms and the kitchen. We often use a manifold for PEX, which gives each fixture its own line and shutoff in one spot, so a single repair doesn't mean shutting water off to the whole house.

• Copper: rigid, heat tolerant, long track record
• PEX: flexible, fewer fittings, fewer wall openings
• Manifold systems: individual shutoffs for each fixture
• Hybrid: copper in the basement, PEX in the walls

The biggest worry most people have is torn up plaster. We plan routes before cutting anything. Old Saint Paul houses often have chases next to chimneys, in closets or behind stair walls where pipes can run with very little demolition. In balloon framed homes, open stud bays sometimes let us pull lines from basement to attic without opening walls between floors.

When we do need access, we cut small, neat openings at fixtures and where lines change direction. We protect floors and furniture, use dust control, and keep each opening as small as we can. After the repipe, we close the openings with drywall or plaster patches ready for paint, or leave them neat for a finisher you hire if you prefer.

A full repipe covers the main supply line from the meter, the hot and cold distribution lines throughout the house, and the branch lines to every fixture. We install new shutoff valves under sinks and toilets and new supply lines to fixtures. We also look at the water heater connections, laundry valves and outdoor faucets, and replace those that are worn or corroded.

Some homeowners choose a partial repipe instead, replacing the worst sections first. That can make sense if the main runs are already copper and only branches remain galvanized. We'll tell you plainly what we see, and you can decide the scope. Either way, we pressure test the new system before closing anything up.

Most families stay home during a repipe. We plan the work so water is off for as short a time as possible, typically during the day, with service restored each evening when we can. A typical house takes two to five days, depending on size, number of bathrooms and how hard the routes are to reach.

Before starting, we'll walk through the plan, which rooms we'll work in each day, and when water will be off. We pull the city plumbing permit and schedule inspections. At the end, we flush the new lines, check every fixture for flow and leaks, and show you where the new shutoffs are.