Plumbing & Leak Repair

Plumbing in a mobile home works differently than plumbing in a site-built house, and that difference matters when something goes wrong. The supply lines and drain lines in a manufactured home run through the crawlspace underneath the floor, not through walls and basements like a conventional home. That means a leak under a mobile home doesn't drip into a visible basement, it drips onto the ground, soaks into insulation, saturates the vapor barrier, and quietly rots the subfloor from below. By the time you notice a soft spot in the floor or a musty smell in the room, the leak has been doing damage for weeks or months.

Murray Mobile Home Services provides plumbing and leak repair for manufactured homes across Florida. From fixing a dripping supply line under the home to replacing a shower unit or repairing water damage caused by a plumbing failure, we handle the work that happens where the crawlspace meets the living space.

What Makes Mobile Home Plumbing Different

If you've ever called a traditional plumber to work on a mobile home, you may have gotten a "we don't work on mobile homes" response. There's a reason for that. Manufactured home plumbing uses different materials, different sizing, different connection methods, and a different layout than site-built homes.

Supply lines in a mobile home are typically 1/2 inch for individual fixtures and 3/4 inch for the main line and water heater connections. These are smaller than the standard sizes used in conventional construction. The pipe material varies by the era the home was built in (more on that below), and the fittings are often specific to manufactured housing rather than the standard hardware store inventory.

Drain lines are usually 1-1/2 inch to 3 inch PVC or ABS, running through the crawlspace beneath the home to a central drain that exits to the sewer or septic connection. Because these lines run horizontally across the crawlspace with relatively little slope available, they rely on precise grading to drain properly. If the home settles unevenly or gets knocked out of level, drain lines can lose their grade and develop slow drains, standing water, or backups.

Fixtures in mobile homes (tubs, showers, sinks, toilets) are often manufactured-home-specific sizes. A standard site-built shower base may not fit a mobile home shower opening. A standard toilet may not align with the drain flange spacing. Replacement parts and fixtures need to be sourced from manufactured home suppliers or carefully matched to the home's specifications.

What's in Your Pipes? A Timeline

The type of supply pipe in your mobile home depends almost entirely on when the home was manufactured. Knowing what you have helps you understand the risks and the options.

Before 1978: Galvanised Steel or Copper

Homes from this era may still have original galvanised steel supply lines. These pipes corrode from the inside out over decades, gradually restricting water flow and eventually developing pinhole leaks. Copper was also used in some homes from this period and holds up better, but can develop issues at joints and connections over time. If your home still has galvanised supply lines, they are well past their expected lifespan and replacement is a matter of when, not if.

1978 to Mid-1990s: Polybutylene

This is the era that causes the most problems. Polybutylene (PB) is a grey plastic pipe that was widely used in manufactured homes (and site-built homes) during this period. It was inexpensive, easy to install, and seemed like a breakthrough material at the time.

The problem is that polybutylene degrades when exposed to chlorine and chloramine, which are standard disinfectants in municipal water supplies. The pipe becomes brittle from the inside, develops micro-fractures, and eventually fails. The failures are unpredictable, a pipe that looks fine on the outside can rupture without warning. Multiple class-action lawsuits resulted from polybutylene failures, and the material was taken off the market by the mid-1990s.

If your mobile home was built between roughly 1978 and 1996 and you haven't had the supply lines replaced, there is a high probability you have polybutylene. The pipe is grey in colour (sometimes white or blue in other applications, but grey in most mobile homes). The fittings, particularly the original plastic (acetal) fittings, are the most common failure point. A polybutylene system with plastic fittings is considered a ticking clock by most plumbing professionals.

Mid-1990s to Early 2000s: CPVC

Chlorinated polyvinyl chloride replaced polybutylene as the standard in many manufactured homes. CPVC is a rigid, cream-coloured pipe that handles hot and cold water well and resists chemical degradation better than PB. However, CPVC becomes brittle with age and UV exposure. It cannot flex, so any stress on a joint (from home settling, vibration, or someone bumping a pipe in the crawlspace) can cause a crack. Freezing will shatter CPVC.

2000s to Present: PEX

Cross-linked polyethylene (PEX) is the current standard for manufactured home plumbing and is widely considered the best option available. PEX is flexible, resistant to freezing (it can expand up to 15% before bursting), resistant to chemical degradation, and available in red (hot) and blue (cold) for easy identification. It requires fewer joints than rigid pipe, which means fewer potential failure points. If you're replacing supply lines in a mobile home today, PEX is the material of choice.

Where Leaks Hide

The challenge with plumbing leaks in a mobile home is that the evidence often shows up far from the source. Water follows gravity and the path of least resistance. A leak at a supply line connection near the water heater can travel along a joist or the belly wrap, pooling at a low point twenty feet away. The soft spot you feel in the hallway floor might be caused by a leak in the bathroom that's been running along the subfloor for months.

Because the plumbing runs through the crawlspace, leaks drip onto or near the vapor barrier and insulation. A slow drip can saturate insulation without leaving any visible sign above the finished floor for a long time. The first indication is usually a soft spot in the floor, a musty smell, or a spike in the water bill.

Finding the actual source requires getting into the crawlspace and tracing the path from the damage back to the origin. It's not always where you'd expect.

Services We Provide

Our plumbing work focuses on the areas where plumbing meets the structure of the home, the crawlspace connections, the fixtures, and the damage that plumbing failures cause to the floor and subfloor systems. The services we handle include:

Leak detection and repair: locating and fixing leaks in supply lines, drain lines, and fixture connections in the crawlspace and at fixture points within the home.

Pipe repair and replacement: repairing damaged sections of supply or drain lines, or replacing failed pipe runs with PEX (for supply lines) or PVC (for drains).

Shower replacement: removing and replacing mobile-home-specific shower units, including the drain connection, supply lines, and any subfloor work needed around the shower pan area.

Fixture repair and replacement: faucets, toilet connections, water heater connections, and supply valves that are leaking, corroded, or no longer functional.

Water damage repair: when a plumbing failure has caused damage to the subfloor, insulation, or vapor barrier, we address both the plumbing issue and the resulting structural damage. Fixing the leak without fixing the damage it caused (or vice versa) doesn't solve the problem.

Plumbing and Your Crawlspace

A plumbing leak in a mobile home isn't just a plumbing problem, it's a crawlspace problem. Water that escapes from a leaking pipe enters the crawlspace environment and affects everything in it. Insulation absorbs the moisture and sags. The vapor barrier may pool water or get displaced. The subfloor above the leak softens and begins to rot. If the skirting has gaps, the added moisture can attract pests.

This is why plumbing repairs in a mobile home often extend beyond the pipe itself. When we're under the home fixing a leak, we assess the surrounding crawlspace condition and let you know if the leak has caused damage that needs attention. If floor repair, insulation replacement, or vapor barrier work is needed alongside the plumbing fix, we can handle it all in one project rather than having you schedule separate visits with separate contractors.

Drains That Don't Drain

Slow drains in a mobile home aren't always caused by clogs. Because drain lines in a manufactured home run horizontally through the crawlspace with minimal slope, they depend on precise grading to function. If the home has settled unevenly since it was installed, or if it needs leveling, the drain lines may have lost their grade. A section of pipe that used to slope toward the outlet may now be flat or even sloping slightly backward, creating a low point where water and waste collect.

If you're experiencing persistent slow drains that don't respond to conventional clearing, the issue may be structural rather than plumbing. Having the home checked for level and the drain lines inspected for grade can identify whether repositioning the home or re-grading the drain lines is the actual solution.

A Note on Polybutylene

If your home was manufactured between the late 1970s and mid-1990s and you haven't had the supply lines replaced, we strongly recommend having the system assessed. Polybutylene doesn't give reliable warning signs before it fails. A pipe that looks intact today can rupture tomorrow, flooding the crawlspace and potentially causing thousands of dollars in damage to insulation, subfloor, and floor joists.

Replacing polybutylene with PEX is a straightforward job that eliminates the ongoing risk. The transition fittings and connection methods are well-established, and PEX's flexibility makes it well-suited to the crawlspace environment. If your home still has the original grey polybutylene lines, replacing them before they fail is significantly less expensive and less disruptive than dealing with the aftermath of a blowout.

Something Leaking? Let's Track It Down

If you've noticed a soft spot in the floor, a persistent drip underneath the home, water bill increases you can't explain, or a musty smell concentrated in one area, there's a good chance plumbing is involved. Call us and describe what you're seeing. We'll get under the home, find the source, and give you a clear picture of what needs to happen to fix both the plumbing issue and any damage it's caused.