Two stages, two sets of tools
New plumbing generally happens in two stages. Rough-in comes first, while the walls and floors are open: supply lines and drain, waste and vent pipes are run, supported and tested. Trim-out comes after the walls are finished: fixtures, faucets, stops and supply connectors are set. The tools overlap, but thinking in stages helps you avoid hunting for a tool at the wrong moment.
The tools that cut, join and thread pipe by material are their own topic, covered under pipe fitting tools. This article focuses on everything around those operations that gets a new fixture working.
Layout and measuring
Good installation starts with knowing where things go. Fixture manufacturers publish rough-in dimensions, such as how far a toilet drain sits from the wall, and those documents should come out before any pipe is cut.
- A tape measure and pencil or marker for locating drain and supply points. Keep the reading-tape-measure habits in mind, since a misread by a fraction of an inch can cause trouble later.
- A level, plus a laser level if you want a straight reference line across a room or along a wall.
- A stud finder to see where framing lies before you drill, and a pencil to mark it. Our note on stud finder use applies here.
- A combination square for marking, and a habit of checking square on boxes and mounting boards.
- A slope gauge or a level with a slope guide. Drain lines need a steady downhill pitch. The exact requirement is set by local code, so look it up rather than guessing.
Opening and drilling framing
Pipes run through studs and joists, so you will be making holes and notches.
- A drill with a hole saw or auger or spade bit makes the pass-through holes. A right-angle drill can help between studs. Our drill bit types article covers which bit suits which job.
- A reciprocating saw is useful for cutting out old pipe or opening a wall. Its plunge cuts are quick but can strike hidden pipes and wires, so turn off power and water before cutting into a wall, and shallow cuts are safer.
- A drywall saw and utility knife for access openings. Rules for how large a hole you may bore in a stud or joist are set by building codes, and drilling too large a hole weakens framing. Check local requirements and ask a professional if you are unsure.
- A step drill bit can be handy for neat holes in thin metal, such as sinks or steel panels.
- Nail plates, where code or good practice calls for protecting pipe from screws and nails that might later be driven into a wall.
When drilling or cutting into walls, wear eye protection and a dust mask, and check for electrical cable first. Unplugging tools before changing bits is a basic habit worth keeping.
Supporting and securing pipe
Pipe needs support at intervals to prevent sagging and noise. The right spacing depends on the pipe material and local code.
- Pipe straps, clamps and hangers matched to the pipe material.
- A cordless drill or impact driver with the right driver bits for the screws. Our guide to pilot holes explains how to avoid splitting wood.
- Blocking and brackets to hold stub-outs, the short pipe ends that stick out of a wall, solidly in place for the fixture.
- Wall anchors are sometimes needed for fixtures that mount to hollow walls or masonry.
Making connections
The connection tools depend on the pipe, but a few are common to nearly every job:
- Adjustable wrenches and channel-type pliers for compression and threaded connections.
- A basin wrench for faucet nuts in tight spots.
- Braided supply lines or flexible connectors, which are components rather than tools, but they simplify hooking up faucets and toilets. Follow the manufacturer’s tightening guidance; overtightening can damage fittings and gaskets.
- Thread sealant or PTFE tape where the fitting instructions call for it.
- Plumber’s putty or silicone for sealing certain drains. Check the fixture’s instructions to see which it needs. Good caulking tools make a neat bead where a fixture meets a wall or countertop.
- A closet auger and basic toilet setting tools, including a wax ring or similar seal, shims and a closet bolt wrench or socket.
Shutoffs, venting, and testing
New work needs to be tested before it is covered up. Many installers use a test plug or cap to close the end of a line, a gauge and pump for a pressure test, or simply fill the line and check each joint. Requirements for testing and inspection differ by jurisdiction, and in some places a permit and inspection are required before walls are closed. Look into this before starting.
A shutoff valve at each fixture, and a main shutoff you can find quickly, are worth installing or confirming. Keep a bucket, towels and a wet/dry vacuum nearby, since lines hold water even after they are drained.
Working conditions
Rough-in often happens in crawl spaces, basements and attics where lighting is poor. Portable work lights make a real difference. Knee pads, gloves, safety glasses and a hard hat in low-clearance areas all earn their keep. If you use a torch, keep a fire extinguisher nearby and shield wooden framing with a heat-resistant barrier. Our overview of personal protective equipment is a useful reference for choosing gear.
When to call in help
Some parts of installation, such as gas lines, main drain connections or changes to a water heater, can be unsafe or illegal for unlicensed people to attempt. This guide is general information, not professional trade advice. When in doubt, check local rules and consult a licensed plumber.