Blog › October 21, 2026 · 5 min read

Are supply pipes typically included in a sink installation quote?

Most sink installation quotes include the flexible supply lines that run from the shutoff valves to the faucet, but they usually don't include replacing the actual supply pipes or shutoff valves behind the wall or under the floor. If those are old, corroded, or leaking, that's additional work and should be called out separately in the estimate.

What "supply pipes" actually means here

There are three different things people lump together under "supply pipes," and they matter for pricing. First is the supply line itself — the short, flexible braided stainless steel or plastic hose that runs from the wall valve to the faucet or sink. Second is the shutoff valve (sometimes called an angle stop), the small valve under the sink that lets you cut water to that fixture without shutting down the whole house. Third is the actual rough-in pipe inside the wall or floor — copper, PEX, CPVC, or in older homes, galvanized steel or polybutylene — that feeds water to that shutoff valve in the first place.

A standard sink installation almost always covers the first item: new supply lines, because they're cheap, they wear out, and reusing an old one on a new faucet is asking for a slow drip later. The second and third items are where quotes diverge. Some plumbers include new shutoff valves as a matter of course if the old ones look rough. Replacing the pipe behind the wall is a different job entirely and should never be assumed as included unless it's written into the scope.

What's usually covered in a standard quote

If you're having a sink or faucet installed and the existing plumbing is in reasonable shape, a typical quote covers removing the old fixture, connecting new supply lines to the existing shutoff valves, hooking up the drain assembly, and testing for leaks. This assumes the shutoff valves turn freely, don't weep when operated, and the threads aren't stripped or corroded.

It also usually assumes there's enough room to work. Under-sink cabinets in South Florida homes often get packed with cleaning supplies and trash bins, and tight quarters can slow down even a simple swap. None of that changes the plumbing scope, but it's worth clearing the cabinet before anyone shows up so the quote and the actual job match.

• New flexible supply lines (braided stainless is the standard now, not the old plastic kind)
• Reconnection to existing shutoff valves, assuming they're functional
• Drain trap and P-trap connection or reuse
• Leak test once water is back on

Why South Florida plumbing often needs more than a swap

Homes built before the mid-1990s in Miami-Dade and Broward sometimes still have galvanized steel supply pipes or, in some subdivisions, polybutylene — a gray plastic pipe used widely in the 1970s and 80s that's known for failing at the fittings. Neither plays well with a simple fixture swap. Galvanized pipe corrodes from the inside, narrowing the opening and sometimes crumbling when a wrench puts any torque on it. Polybutylene gets brittle with age and chlorine exposure, and a shutoff valve that looks fine can snap off in your hand once you try to turn it.

Hard water and humidity add their own wear. Mineral scale builds up inside valves and at threaded connections, which is why a shutoff that hasn't been touched in years often seizes, cracks, or starts weeping the moment it's operated. Salt air plays a role too, especially in homes closer to the coast, where exposed metal fittings under a sink can show surface corrosion even indoors because of how much moisture is in the air for months at a time. None of this shows up in a phone estimate — it shows up when someone opens the cabinet doors and looks.

Signs you'll need pipe or valve work, not just a sink swap

A few things reliably turn a straightforward installation into a bigger job. If the shutoff valve doesn't turn, or turns but still drips past the handle, it needs to be replaced before anything else happens — there's no safe way to install a new faucet on a valve that won't fully shut water off. If you see green or white crusty buildup around a fitting, that's mineral deposit from a slow leak that's been there longer than you think. Rust-colored water when you first turn on the tap after the house has sat unused points to galvanized pipe corroding internally.

Soft spots in the cabinet floor or a persistent musty smell under the sink usually mean water has been getting past a connection for a while, which can mean the cabinet base and possibly subflooring need attention in addition to the plumbing. None of these are things a contractor can diagnose accurately over the phone. They're also the reason a quote given sight-unseen should always be treated as a starting point rather than a final number.

How to get a quote that actually holds up

The fastest way to avoid a surprise mid-job is to send clear photos before anyone commits to a number: the area under the sink with the cabinet doors open, a close-up of both shutoff valves, and a wide shot showing how much room there is to work. If you already know the fixture you want installed, include the model or at least a photo of the box, since some faucets need different supply line sizes or come with their own hardware.

Ask directly whether the quote assumes the existing shutoff valves are usable, and what happens to the price if they turn out not to be. A contractor who's done this kind of work will have a straight answer instead of a vague one. If the home is older, galvanized or polybutylene pipe is common enough that it's worth asking about by name rather than waiting to find out partway through.

How Gold Hands handles sink and faucet jobs

For faucet and sink installation, Gold Hands Miami gives estimates by phone or from photos rather than guessing at a flat number, because the condition of the shutoff valves and the supply pipe behind the wall genuinely changes the scope. Labor runs at an hourly rate of $100* with a two-hour minimum, so a straightforward swap with working valves is a different visit than one that turns into replacing corroded shutoffs or a section of old pipe. If the pipe issue runs into the wall or involves a permit-level repipe, that part gets referred out to the right trade rather than forced into a job it doesn't belong in.

* Minimum visit $200 — smaller jobs can be combined into one visit.

You can see more on what's typically involved on the faucet installation page, or book directly online with a deposit to lock in a visit. For anything that looks more involved than a standard swap — rust-colored water, a cabinet floor that's soft, valves that won't turn — it's worth mentioning that upfront by phone at (786) 788-8714 so the person coming out brings the right parts the first time.

Frequently Asked Questions

Does a sink installation quote include new shutoff valves?

Not automatically. Most quotes assume the existing shutoff valves work and just need the supply line reconnected. If a valve is seized, leaking, or won't fully shut off, replacing it is additional work that should be priced once it's actually inspected.

What if my supply lines are already leaking before the new sink goes in?

That's worth mentioning when you book, since it usually means the valve or the line itself needs replacing regardless of the new fixture. Photos of the leak and the area around it help get an accurate scope before anyone shows up.

Can I buy my own sink or faucet and just have someone connect the existing pipes?

Yes, that's common. Bring or send a photo of the box so the supply line size and connection type can be confirmed ahead of time — some faucets use different thread sizes or come with proprietary fittings.

Do I need a permit to replace a supply pipe behind the wall?

Pipe replacement that goes beyond the shutoff valve and into the wall or floor often falls under plumbing permit rules in Miami-Dade and Broward, depending on scope.

How is a supply line different from a drain line in the quote?

The supply line brings water in and is almost always included as a simple swap. The drain line carries water out through the P-trap, and whether it's included depends on whether the existing trap fits the new sink or needs new parts — worth asking about specifically if you're changing sink styles.

Why does my older South Florida home seem to need more pipe work than newer houses?

Homes built before the mid-1990s sometimes have galvanized steel or polybutylene supply pipes, both of which degrade with age and don't hold up well to being disturbed. Combined with hard water scale and humidity, valves and fittings in older homes fail more often during a routine fixture swap than in newer construction.

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