Plumbing installation in Dedham, MA covers any new plumbing work: adding a bathroom, moving a kitchen sink, running a line to a garage, or fitting a new fixture. In Massachusetts, only licensed plumbers may do this work, and a permit comes first. We schedule these jobs as planned work, with same-day appointments offered when available for smaller installs. This page lays out the rules, the choices, and the questions to ask.
Start with the permit and the code.
The state plumbing code, 248 CMR 10.00, governs the installation, alteration, removal, replacement, repair, or construction of plumbing. Mass.gov's consumer fact sheet says a local plumbing inspector must issue a permit before this work starts, and that permits go only to licensed plumbers.
In Dedham, the Building Department has a Plumbing/Gas Division, and permit applications go through the OpenGov online portal. For you, this means a contractor who says you can skip the permit is a red flag. Minor repairs like fixing a leaky faucet need no permit, but replacing or relocating fixtures or piping does. Ask to see the permit number before work begins.
Which installation jobs are we talking about?.
Fixtures and appliances.
Sinks, toilets, tubs, showers, dishwashers, and disposals all connect to supply and drain lines. A simple swap of a like-for-like fixture is often quick. Moving a fixture means moving the lines, and that is where permits, venting, and wall access come in.
New lines and extensions.
A bathroom in the basement, a laundry room, or an outdoor spigot all need new supply and drain runs. Drains need slope and venting, and basement bathrooms often need a pump if they sit below the sewer line. Ask the plumber how the drain will work before the floor is cut.
Water heaters and appliances with gas.
Water heater work has its own rules, including a relief valve and a safe waste pan in some installs. See water heater installation for details. Gas piping falls under a separate fitting license, though a licensed plumber may also do gas fitting.
Planning plumbing work? Call to schedule a visit.
Call (617) 752-0573Planning a remodel without surprises.
Remodels go well when plumbing is planned before cabinets and tile are ordered. Decide fixture locations first. Then confirm where the supply, drain, and vent can run. A change after drywall is up costs far more than a change on paper.
Dedham's housing is largely older. The Town's Master Plan says 74 percent of houses were built before 1978. In practice, that means you may find mixed pipe materials when walls open, and the plumber might recommend replacing a section while access is easy. Ask for that decision to be written into the scope. If the scope grows into a bigger replacement, our repiping page explains the trade-offs.
Adding or moving a water line.
A new line to a garage, shed, or addition starts with Dig Safe. Massachusetts requires a call to 811 at least 72 business hours before excavation, and it applies to homeowners too. Municipal water and sewer lines may not be marked, so the plumber should say how they will locate them.
For a buried supply line, the state residential code lists a frost depth of 48 inches, which is the depth to plan around so the pipe stays below ground frost. If the new run ties into your service line, ask the Dedham-Westwood Water District where its responsibility ends and yours begins. Our water line repair page covers what happens when an existing line fails.
New construction and additions.
New construction is about layout, not diagnosis. The plumber works from drawings, roughs in supply and drain lines before the walls close, and an inspector reviews the work at stages. Ask which inspections are scheduled and who will be on site when the inspector comes.
In a new addition, put shutoff valves where you can reach them, and leave access panels at tub traps and key valves. A little planning here saves a future wall opening.
Backflow and hose connections.
The plumbing code requires a backflow preventer or vacuum breaker on hose connections, and the District recommends hose-bib vacuum breakers for all hose connections. A vacuum breaker keeps hose water from being drawn back into the house supply. If you are adding an outdoor faucet or irrigation, ask the plumber to include the right device and explain it.
Choosing the installer: questions that matter.
| Question | Good answer. |
|---|---|
| Are you a licensed plumber? | Yes, with a license number you can check. |
| Who pulls the permit? | The licensed plumber, in their name. |
| What is in the written scope? | Fixtures, pipe material, access, patching. |
| Who patches the drywall? | Named in the quote. |
| What happens if walls reveal old pipe? | A written change process. |
You can verify a license through the state's eLIPSE portal or by calling the Board of State Examiners of Plumbers and Gas Fitters at 617-727-9952. A license type and number should appear on the contractor's ads and signs.
What plumbing installation costs.
- Number and type of fixtures, and whether you are moving them..
- Pipe material, length of new runs, and whether drains need venting changes..
- Access: open framing, finished walls, or a concrete floor..
- Permit, inspection, and any excavation for buried lines..
- Finish work: drywall, tile, and paint, which are often separate trades..
Insurance does not usually pay for planned installation. Homeowner policies generally cover sudden and accidental damage rather than wear and tear or upgrades, so ask your insurer if you are unsure. Want your real number? Call (617) 752-0573.
Before the plumber arrives.
- Measure and mark where each fixture is going..
- Have the fixtures on site, or at least the model numbers..
- Clear the work area and protect floors..
- Find your main shutoff and test it..
- Ask your landlord or HOA for approval if you do not own the property..
Frequently asked questions.
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Replacing or relocating fixtures or piping needs a permit, which a licensed plumber pulls. Minor repairs like a leaky faucet do not. Call the Dedham Building Department's Plumbing/Gas Division if you are unsure.
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Use the state's eLIPSE portal or call the Board of State Examiners of Plumbers and Gas Fitters. The license type and number must appear on signs and ads.
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Massachusetts says only licensed plumbers may do plumbing work, and permits go to them. Ask the Dedham Building Department what a homeowner may do. Do not guess, because unpermitted work can cause trouble when you sell.
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A fixture swap can take hours. A new bathroom takes days and depends on inspection timing. Your plumber should give a schedule with inspection steps.
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Often yes, but drains below the sewer level may need a pump. Ask the plumber how the drain will work and what the vent plan is before work begins.
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Get your landlord's written approval first. The owner usually authorizes plumbing changes, and a permit goes in the licensed plumber's name.
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Ask for a written change process before work starts. If old pipe is found, the scope should say how you will approve extra work.
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Yes, including Norwood and Walpole. The plumbing services hub lists every service.
Codes, standards and sources.
Plumbing work in Massachusetts is governed by 248 CMR 10.00, the Uniform State Plumbing Code, and plumbers are licensed by the Board of State Examiners of Plumbers and Gas Fitters. You can read the state's consumer fact sheet on plumbers and gas fitters before you hire anyone.
Local facts on this page come from the Dedham-Westwood Water District, the Town of Dedham, the other towns named and Mass.gov, and were checked in October 2026. Where a fact could not be confirmed, the page says to ask the utility or the town.