What Is Rough-In Plumbing? Preparation, Consideration, Tools, And Cost

Rough-in plumbing is a construction stage that comprises routing of pipes via wall cavities, installing vents stacks to the roof, and joining water supply line and drain lines to septic systems, water supply valves, or sewer systems. However, installation of building fixtures such as toilets, sinks, and showers is not done during rough-in plumbing. 

Preparation Of Rough-In Plumbing 

It is vital to ensure that all rough framing in your new building house is complete before sending in your plumber to start the rough-in plumbing phase. Besides that, you have to ensure your plumber has all plans, product specifications, cabinet layout, among others, before starting the work. It is helpful for your plumber to work on the framed home to solidify and check sites of every plumbing fixture, washer, /dryer hookups, water heater, core water hookup, and pipes required to join the water and drain lines. 

Throughout The Rough-In Plumbing Phase, The Following Are Done:

1. Routing pipes via the wall cavities 

2. Installing vent stacks to the roof

3. Ensuring drain lines and water supply are joined to septic systems, sewer systems, or core water supply valves

4. Pipes installation are made 

5. Excavation and placing of underground piping that goes from utility connection to a central structure is finalized 

6. Installation of fixtures or end elements will not be done in this phase 

Crucial Consideration Throughout Rough-In Phase:

1. Gravity is essential for proper draining. Therefore, the wastewater drain line pipe should be connected in a position that faces downward. If not done correctly, waste and water won’t drain effectively. It is vital to realize that angling too much might cause issues linked with draining too quickly as well. 

2. The wastewater system should be vented to make sure waste is eliminated effectively and safely.

3. Once the rough-in plumbing phase and inspection are complete, the remaining parts of the plumbing system may be finalized later in the building process.

Rough-In Tools And Materials

The plumbing contractor uses hand tools and power tools to cut and connect pipes in rough-in. They use a manual tubing cutter. To clean copper, plumbers use wire brushes or special sandpaper known as emery cloth, whereas for solder copper, a cleaning compound known as flux is used, a handheld torch and solder. When it comes to cutting the drain, plumbers use handheld hack saws or chop saws.

Moreover, plumbers connect plastic pipes using glue-like solvent cement and join iron pipes with mechanical fittings.  The frame needs various cutting and drilling tools to route and secure pipes within the house, comprising circular saws, reciprocating saws, and power drills. 

The Expectation For The Rough-In Plumbing 

Constructing trade professionals see the rough-in as final and not the work-in-progress. The same should apply to homeowners executing remodeling work. The rough-in must be their best effort, work done exactly to their requirement.  But if the inspector orders a modification or a homeowner needs some changes, the work will be done quickly since the work remains accessible. 

Rough-In Plumbing Cost

The cost of rough-in plumbing varies depending on the size of a home. For a 2,300 square feet home with 2-3 bathrooms, it will cost you $7,000-$15,000 to complete the rough-in stage in new construction. Since rough-in doesn’t include installation of fixtures, it is excluded in the cost. However, you will pay between $600 and $1,600 for the installation of one fixture. The total cost for fixtures thus ranges from $1,500-$2,000. 

Understanding the bid process in new plumbing installation is essential in calculating the final cost. For instance, the plumber can bid by a point or per fixture. There is a specific point value for each fixture; 0.5 point for refrigerator, dishwasher, toilet, 1 point for shower or sink, and 2.5 points for bathrooms. 

The table below can help you in approximating the rough-in plumbing cost in your building:

Rough-In Cost For Homes With ¾ And Full Baths

No. Of BathsApprox. Cost 
2$3,000 – $8,000
3$4,500 – $12,000
4$6,000 – $16,000

N/B: It cost 60% less to do rough-in plumbing in homes with half baths that have few fixtures

Cost Of Rough-In Per Room Or Appliance

Room/ApplianceApprox. Cost
Gas applainces (furnace, stove, dryer)$1,800 – $4,800
Washer$600 – $1,600
Tankless Water Heater$1,100 – $3,200
Electric or Gas Water Heater$600 – $1,600
Kitchen$1,600 – $3,200
Full Bathroom for one room$1,500 – $4,000

What Is Finish Plumbing?

This refers to work that happens after interior finishing, like drywall and plaster. In the finish plumbing phase, the following will be done:

1. Plumbers Install and connect plumbing fixtures, such as toilets, sinks, and tubs are finalized 

2. Removal of caps on drain and water supply pipes is done 

3. Installation of under sink drain supplies 

4. Installation of water supply values and water supply lines 

5. Caulking and sealing of plumbing fixtures and testing of new connections is finalized 

Finish Plumbing Tools And Materials 

Like the rough-in plumbing, finish plumbing requires some tools as well. These tools are used for twisting and tightening drain assemblies and plumbing fixture parts. Typical finish plumbing tools comprise a wide variety of wenches, such as pipe wrenches, box wrenches, and adjustable wrenches. Plus, plumbers carry a long set of screwdrivers and other general-purpose tools to finalize finished plumbing works. 

How Long Does Plumbing Rough-In Take?

Plumbing rough-in takes several days to be completed.  Whereas average home building only requires approximately three to five days for this process, numerous factors can extend it. 

The larger building projects, such as multi-family apartments, will need more period for rough-in plumbing. The same applies to larger single-family homes with many bathrooms. 

Climate also plays a crucial part. Rain and windstorms can interrupt any building project, comprising plumbing rough-in. 

Having an adequate human resource to finalize the work in time is vital to reducing the time required for rough-in plumbing. However, having a conflicting arrangement with other construction contracts or inspectors can lead to delays as well. For example, electricians usually install the primary electrical supply lines, whereas plumbers do the rough-in task. If the electricians delay with their work, pouring foundation and inspections could take experience setback as well. 

What Comes First, Plumbing Or Framing?

Framing comes first before plumbing. Next after framing is the mechanical rough-in plumbing, HVAC, electrical, media wiring, gas, and fireplace installations. If on a slab, framing happens before rough-in. But if on a basement, plumbers come in to install rough plumbing before framing. 

Should You Do Electrical Or Plumbing First?

It is perfect for most home construction projects for plumbing fixtures, such as tubs and toilets, to be installed first before electrical. While installing plumbing rough-in, all water supply, water pipes, and drain pipes are connected via holes in the home’s studs and framing structure. 

What Is Included In Rough Framing?

It entails fittings together pieces of materials, such as brick, concrete, steel, and wood. Wood is the most used material to frame houses—rough framing new home building and constructing room additions. 

What Are The Three Stages Of Plumbing?

Plumbing Can Be Divided Into Three Stages:

1. Underground rough-in phase

2. Aboveground rough-in phase

3. Finishing/trim-out phase 

Underground Plumbing

This is the first stage in plumbing where the plumber identifies all the supply and waste connections from the building to the public utilities. The entry and the exit of the plumbing system from the structure are also established. 

Aboveground Rough-In Phase

The Aboveground Rough-In Stage Involves The Following:

1. Cutting holes in floors, ceiling, or wall to hang or attach pipes that will be connected to fixtures

2. Installation of supply and waste pipes in the building

3. Joining pipe tuns using welding tools or special chemical where plastic pipes are used

4. Operation of power tools such as propane torches and threading machines

Finishing/Trim-Out Phase 

This is the last stage in plumbing where the plumber installs the building fixtures such as showers, sinks, and toilet appliances like water heater and water purification system. Installation of automatic control to regulate the pressurized pipe system can be done during this stage. 

After the finishing stage, the plumbing system will be complete. After that, periodic maintenance is carried out to keep the system running smoothly. Service and maintenance involve; checking test gauges, lubrication levels, meters and pumps, verification of the operating system, repair of faulty components or fixtures, and regulation of flow and usage rates. 

Why Is PEX Plumbing Bad?

Some people say PEX plumbing is bad since piping fails once exposed to direct sunlight before its installation or exposed to chlorine around the water. Also, PEX piping is susceptible to contact with such solutions as oxygen and petroleum products. Furthermore, it can leak toxic chemicals and is prone to destruction by pests.

Final Word

New construction is a vast project that demands multiple contractors to work together. There are a lot of things to be done, from rough-in to fixture installation. In rough-in, the plumbers identify the supply and waste connection and install the pipes to the building. After the rough-in, the remaining part will install the building fixtures such as sinks, showers, and toilet appliances. A plumber’s work does not end there, as there is a need to do perioding service and maintenance to keep the system in good shape. 

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