Yes, you can sometimes convert a tub to a shower without major plumbing relocation. This is most likely when the new shower stays within the existing bathtub footprint and its drain position works with the current plumbing. That does not mean every old plumbing part should remain untouched. The drain, P-trap, shower valve, supply lines, and connections still need to work with the new shower design.
This distinction matters. Keeping plumbing in roughly the same location can simplify a tub-to-shower conversion. Keeping plumbing that is damaged, poorly positioned, or incompatible can create problems later. Before choosing a shower base or wall system, it helps to know what can stay and what may need adjustment.
What Plumbing Can Stay During a Tub-to-Shower Conversion?
A bathtub uses several plumbing components. Each one should be considered separately during the conversion.
| Existing Component | Can It Sometimes Stay? | When It May Need to Change |
| Drain location | Yes | New shower base does not line up with it |
| Drain piping | Sometimes | Pipe is damaged, poorly configured, or incompatible |
| P-trap | Sometimes | Condition or setup does not suit the new shower |
| Hot and cold supply lines | Often | Pipes are damaged or the fixture location changes |
| Shower valve | Sometimes | Valve is old, incompatible, or being upgraded |
| Showerhead connection | Often | Showerhead height or position changes |
| Tub overflow | No | A shower does not use a bathtub overflow |
| Plumbing inside the wall | Often | Layout or fixture placement changes |
The key point is simple: keeping plumbing in the same area is different from leaving every part exactly as it is. A remodeler may be able to keep the drain and supply lines in the same general location while still changing fittings, the valve, or other connections.
Tip: Do not choose a shower base from appearance alone. Check the existing drain location first. A compatible base may prevent unnecessary plumbing changes.
The Drain Is Usually the First Thing to Check
The existing drain can determine how simple the conversion will be. Bathtub drains are commonly positioned closer to one end of the tub. A replacement shower base may have a center, side, or offset drain. If the new shower base has a drain opening that works with the existing plumbing location, major drain relocation may not be necessary. If it does not line up, the installer may need to open part of the floor and adjust the drainage system.
The drain evaluation should look at more than its visible location. It may also include:
- Pipe condition
- P-trap location
- Drain slope
- Available floor access
- Connection to the branch drain
- Compatibility with the selected shower system
This is why a drain that appears to be “in the right place” may still require some work.
Does a Shower Drain Have to Be in the Center?
No. A shower drain does not automatically have to be centered.
Different shower bases use different drain positions. Some designs can work with an existing tub drain near one side of the shower.
What matters is that the shower base, drainage system, slope, and plumbing work together correctly. Choosing a center-drain shower simply because it looks standard could create extra plumbing work when an offset-drain system might better match the existing layout.
Tip: If reducing plumbing changes is a priority, ask about shower bases designed around common bathtub drain locations.
Do You Have to Change the Drain Size?
Not every tub-to-shower conversion should be approached with the assumption that the drain must automatically become a specific size.
The 2024 International Plumbing Code lists a minimum 1½-inch waste outlet for showers. Broomfield has adopted the 2024 plumbing code as part of its current building-code framework.
However, that does not mean every existing bathtub drain should simply be reused. The installer still needs to consider the selected shower system, drainage capacity, existing pipe condition, connections, local requirements, and the amount of water the new fixtures may deliver.
A tub-to-shower conversion should not be designed around a drain-size assumption. The existing drainage system should be evaluated against the new shower design.
That approach is more reliable than assuming every project requires the same plumbing modification.
What Happens to the Existing Tub Faucet and Shower Valve?
Removing a bathtub also changes how the wall fixtures are used.
A standard tub-and-shower setup may include:
- Hot and cold supply pipes
- Mixing valve
- Tub spout
- Shower riser
- Showerhead
The tub spout will normally no longer be needed once the tub is removed. Other parts may be reusable depending on their condition and the new fixture design.
The shower valve deserves particular attention.
An older valve may not work with the new trim or fixture package. A homeowner may also decide that opening the shower wall is a good time to upgrade the valve rather than covering an aging component behind a new wall system. The supply lines themselves may still stay in the same wall. This is another example of modifying plumbing without completely relocating it.
Tip: If the walls are already being opened, ask whether replacing an aging shower valve now makes more sense than trying to access it after the new shower is complete.
When Can the Plumbing Usually Stay in the Same Area?
Avoiding major plumbing relocation is more realistic when the new shower closely follows the existing bathtub layout.
Factors that can make this easier include:
- Keeping the shower within the current tub footprint
- Selecting a shower base compatible with the drain location
- Keeping the shower controls on the same plumbing wall
- Using supply lines that are still in suitable condition
- Avoiding major changes to the room layout
A standard or low-threshold shower may also require fewer structural changes than a more complex custom design.
Vision Sync Bath’s tub-to-shower conversion service provides more information about changing an existing bathtub area into a shower. Keeping the plumbing nearby does not guarantee that nothing needs replacement. It simply reduces the amount of relocation that may be necessary.
When Does Moving the Plumbing Make More Sense?
Sometimes preserving the existing plumbing location creates more limitations than benefits.
The New Shower Is Larger
Expanding beyond the original bathtub footprint can change where the drain, valve, or showerhead works best.
A larger shower may also require floor or wall changes that make plumbing adjustments easier to complete during the remodel.
You Want a Curbless Shower
A curbless shower requires careful coordination between the floor structure, slope, drain, and waterproofing.
The existing tub drain may not be positioned where the new design needs it. Floor height can also become a factor. Depending on the bathroom structure, additional floor work may be necessary to create the required slope.
For homeowners considering easier shower access, Vision Sync Bath’s guide to planning a walk-in shower explains several design considerations.
You Want the Controls in a Different Location
The old bathtub layout may put the valve somewhere inconvenient for the new shower. Moving the controls can improve access, especially when someone wants to turn the shower on without standing directly under the water.
That convenience may justify some additional plumbing work.
The Existing Plumbing Is in Poor Condition
Opening the wall or floor may expose corrosion, leaking connections, damaged pipe, or previous work that should not be covered again. Keeping questionable plumbing simply to avoid extra work can create a larger problem later.
Tip: Ask the contractor to separate “recommended replacement” from “required relocation.” They are not the same thing, and the distinction can make a quote easier to understand.
Does Keeping the Plumbing in Place Save Money?
It can.
Avoiding major drain relocation, wall reconstruction, and floor work may reduce project complexity and labor. However, plumbing is only one part of the total tub-to-shower conversion cost.
Wall materials, shower base design, glass, fixtures, grab bars, seating, waterproofing, and hidden repairs can also affect the final price. This is why two projects using the same bathtub footprint can still have very different costs. The goal should not be to avoid every plumbing change. It should be to avoid unnecessary plumbing work while correcting anything that should be addressed before the new shower is installed.
Check the Plumbing Before Choosing the Shower
One of the easiest remodeling mistakes is selecting products before understanding the existing bathroom. A shower base may look perfect online but place the drain on the opposite side of the existing plumbing. Another model may offer a similar appearance while matching the current drain much better.
Before making final product choices, confirm:
- Existing tub alcove dimensions
- Current drain position
- Drain and P-trap condition
- Access below or around the floor
- Supply-line location
- Shower valve condition
- Desired shower-entry height
- New shower-base drain configuration
Wall materials should also be chosen with maintenance and installation needs in mind. Homeowners comparing options can review Vision Sync Bath’s guide to acrylic, solid-surface, and tile shower walls.
Tip: Measure and inspect first. Choose products second. That order can prevent a simple conversion from becoming an unnecessarily complicated one.
What Do Broomfield Plumbing Rules Mean for the Project?
Plumbing changes also need to fit local requirements.
The City and County of Broomfield adopted the 2024 International Plumbing Code, effective April 15, 2026, as part of its current building-code framework.
Permit and inspection requirements depend on the type and extent of work being completed. Altering plumbing may trigger different requirements than simply replacing finishes. Homeowners should therefore confirm permit responsibilities before work begins instead of assuming that every tub-to-shower conversion follows the same process.
For larger projects involving more than the bathing area, homeowners can also review Vision Sync Bath’s information about bathroom remodeling in Broomfield County.
Keeping Plumbing Is Helpful. Keeping Bad Plumbing Is Not.
There is a difference between simplifying a project and cutting the wrong corners.
If the existing drain, supply lines, trap, and valve are in good condition and work with the new design, keeping them in the same area may make sense.
If they are damaged or incompatible, preserving them just to avoid opening a wall or floor can work against the purpose of the remodel.
A good tub-to-shower plan should consider four things:
Condition + compatibility + design + code requirements
The goal is not to keep as much old plumbing as possible.
The goal is to keep the plumbing that still works correctly with the new shower.
Frequently Asked Questions
Can you use the existing tub drain for a new shower?
Sometimes. The drain may remain usable if its location, condition, trap, drainage setup, and connection work with the selected shower system. It should be evaluated before the shower base is chosen.
Does a shower drain have to be in the center?
No. Shower drains can be placed in different locations depending on the shower base and drainage design. Side and offset drain configurations may work better with some existing bathtub layouts.
Do all tub-to-shower conversions require a 2-inch drain?
No blanket rule applies to every project. The 2024 International Plumbing Code lists a minimum 1½-inch shower waste outlet. The selected shower system, existing plumbing, local requirements, and installation conditions still need to be considered.
Can the existing shower valve stay during a tub-to-shower conversion?
Sometimes. The valve’s age, condition, type, location, and compatibility with the new fixtures determine whether it should stay or be replaced.
Is it cheaper to convert a tub to a shower without moving plumbing?
It can be. Keeping usable drains and supply lines in the same general location may reduce demolition and plumbing work. Other choices, including wall materials, glass, fixtures, and repairs, still affect the overall cost.
Does a curbless shower require moving the drain?
Not always, but it can make drainage changes more likely. Floor slope, waterproofing, structural conditions, and drain placement all become more important with a curbless design.
Should you choose the shower base before checking the plumbing?
No. The existing drain location, floor structure, plumbing condition, and bathroom measurements should be checked first. Choosing a compatible shower base may help avoid unnecessary drain relocation.
Plan a Tub-to-Shower Conversion Around the Existing Bathroom
A tub can often become a shower without completely relocating the plumbing, especially when the new design stays close to the existing layout. The safest approach is to inspect the plumbing first and then choose a shower system that works with the space.
Vision Sync Bath can help homeowners plan a tub-to-shower conversion in Broomfield, CO, including shower-base, wall-system, access, and layout decisions.
Explore the tub-to-shower conversion service or contact Vision Sync Bath to discuss the existing bathroom and conversion options.