Expert Poly B Pipe Replacement in Coquitlam BC

1The Inspection — Mapping Every Metre

Before a single pipe is cut, we walk the entire home. That means going into the crawl space with a headlamp, opening the mechanical room, checking under every sink, and tracing where the main supply trunk runs through the structure. We're looking for the full picture — not just the visible grey pipe in the basement, but the buried runs, the concealed branches, and the sections inside finished walls that will need access cuts.

We document everything with photos and sketch out the pipe layout. This becomes the scope of work — the document that defines exactly what gets replaced, where the access points are, and how the new PEX-A system will be routed. No surprises once work starts.

2Shutoff & System Drain

The job starts with a controlled system shutdown. We close the main water supply at the meter, open the lowest fixtures in the home to drain residual pressure, and confirm the system is fully depressurised before any cutting begins. The hot water tank is also drained and isolated — its inlet and outlet connections are almost always Poly B and need to be replaced as part of the job.

Water is off during working hours. Each evening before we leave, we restore the supply so the home is fully functional overnight. Families stay in the home throughout the job — the only real impact is working hours only.

3Mechanical Room Replumb

The mechanical room is always the first area tackled. This is where the water enters the home, where the hot water tank sits, and where the main supply trunk begins. Every Poly B connection in this room comes out — the inlet to the PRV (pressure-reducing valve), the cold supply to the HWT, the HWT outlet, and the first sections of both the hot and cold trunk lines heading out to the rest of the home.

We rebuild this room in PEX-A, properly clipped and labelled. Red for hot, blue for cold. Every connection uses expansion fittings. The finished mechanical room looks cleaner and is significantly more readable than what was there before.

4Crawl Space — The Highest-Risk Zone

In most Coquitlam and Tri-Cities homes, the longest and most deteriorated runs of Poly B are in the crawl space. The main cold supply trunk typically runs from the mechanical room across the full width of the home, branching off to supply various zones. Hot water return lines often run the same path.

Crawl space work is physically demanding — low clearance, poor light, variable moisture conditions. We carry purpose-built equipment for confined-space plumbing: flexible reel lights, cordless expansion tools that work in tight positions, and the right protective gear. PEX-A's flexibility means we can often route long runs without additional fittings, reducing the number of joints in a zone that can't be easily monitored.

5In-Wall Runs — When Drywall Gets Cut

Not all Poly B is accessible without opening walls. Supply lines to second-floor bathrooms typically run up through interior walls from the mechanical room. Branch lines to kitchen and laundry fixtures may be behind finished drywall in a basement or main floor utility room.

When drywall access is needed, we make the smallest cut that allows proper access — typically a horizontal opening at an elbow location, or a short vertical cut along a wall stud bay. We use an oscillating multi-tool with a dust shroud to keep the cut clean and mess minimal. Insulation is pulled and replaced carefully.

All drywall cuts are patched with backing, mesh tape, and joint compound before we leave. We don't do paint matching — that's the homeowner's call — but we leave a clean, sanded, primeable surface. Most homeowners do a quick touch-up with leftover wall paint and you'd never know the wall was opened.

6Bathroom & Kitchen Connections

Every fixture supply connection in the home gets replaced. Under bathroom vanities, we remove the Poly B stub-out and replace with PEX-A running to a new angle stop (shutoff valve). The braided flexible connectors from the shutoff to the faucet are standard and stay. In the kitchen, the same process applies — cold supply to the sink, hot supply, and often a separate cold line for the refrigerator icemaker if present.

Toilets get new supply lines where Poly B is the connection. Laundry rooms get both the hot and cold supply to the washing machine replaced. Every fixture is tested after connection before we move on.

7Pressure Test & Final Inspection

Once all new PEX-A is in and every connection is made, we pressurize the system and hold it at operating pressure for a minimum of one hour before restoring supply to fixtures. We walk every connection point during the test — any fitting that isn't holding is caught and corrected before the job is called complete.

Where a permit was required, we arrange for the City inspector to sign off on the completed work. In Coquitlam and the Tri-Cities, this is a straightforward process — the inspector walks the accessible plumbing, checks that the work was done to code, and stamps the permit completion.

8Insurance Documentation Package

On completion day, we deliver a documentation package that includes: a written scope of work confirming all polybutylene supply pipe was replaced, a signed completion certificate with our BC plumbing license number, photographic documentation of the old Poly B removed and the new PEX-A installed, and the permit completion record where applicable.

This package is exactly what BC insurers require to reverse a Poly B surcharge, reinstate cancelled coverage, or satisfy a replacement condition written into a policy renewal. Most homeowners have their broker submit it within days of receiving it.