Tub to Shower Conversion in Bethesda, MD: Real Costs, Permits, and Local Advice

Should You Convert the Tub at All?

Convert when the shower you use every day is the one over a tub nobody bathes in, when stepping over a 15-inch cast-iron rim has started to feel like a chore, or when the surround tile is loose and water has already found the wall. Those three conditions describe most of the hall baths we open up in Bethesda, Chevy Chase, and Kensington.

Keep the tub in one specific case: it is the only tub in the house and the house sits in a family neighborhood. Buyers with small children in this market still look for a tub, and losing the last one narrows your buyer pool. If the home has two or more full baths, convert the one you use and leave a tub somewhere for the resale conversation.

Do not convert purely as an investment. The Cost vs. Value data for the Washington, DC metro puts a midrange bathroom remodel at roughly 60 percent of cost recouped, below the national figure of about 74 percent. A conversion is worth doing because you will use the room every morning for the next fifteen years, not because it pays for itself at closing.

One cheaper path is worth checking first. If the tub is structurally sound and the problem is a chipped, stained, or dated surface, bathtub refinishing runs $450 to $1,200 and buys you several more years for a fraction of a conversion. We will tell you honestly which one your bathroom needs.

What Bethesda Bathrooms Are Actually Like

The 1940s through 1960s capes, ramblers, and split-levels through Edgemoor, Bradley Hills, Westmoreland Hills, Glen Echo Heights, and the streets off Old Georgetown Road almost all share the same hall bath: about five feet by eight feet, with a 60-by-30-inch alcove tub on the back wall. That alcove happens to be the exact footprint of a generous walk-in shower, which is why most conversions here need no new framing and no wall moved.

What does drive cost in these houses is everything behind the tile:

• • Cast iron. The original tubs weigh 300 to 400 pounds and do not come down a narrow 1950s stair intact. They get cut in place with a demo saw and carried out in pieces, and protecting a plaster stairwell on the way is real labor, not a line you can skip.
• • Plaster and lath, not drywall. Opening a plaster wall to reach the valve produces a bigger patch than clients expect, and the new tile plane has to be brought flat against old wavy plaster before a single tile goes up.
• • Original supply lines. Many of these baths still run galvanized branch lines or early half-inch copper. Once the wall is open, replacing the branch to the new mixing valve is inexpensive. Doing it later means opening finished tile, so do it now.
• • Joist direction. A curbless entry needs the floor recessed. In a typical Bethesda rambler the joists run the short way across the bathroom, so a linear drain along the back wall usually means notching fewer joists than a center drain. If the bath sits over a finished basement, add a ceiling patch below to the scope.
• • Vent stack location. Moving the drain more than a foot or two often means re-venting, and in a two-story colonial that can mean opening a wall on the floor below. Keeping the drain where it is keeps the price in the lower half of every range in this article.

Condos and newer townhomes around the Pike District, Grosvenor, and White Flint are a different problem entirely. Concrete slab floors mean the floor cannot be recessed, and a shared plumbing stack means the drain cannot move. A low-profile base or a tiled pan with a very low threshold is the honest answer there, along with building board approval, a contractor certificate of insurance, and weekday-only work hours.

In the larger primary baths of Potomac, Avenel, and the newer Rockville builds, you often do not have to choose. There is room to convert the tub alcove into a full walk-in shower and still place a freestanding soaking tub elsewhere in the room, which is the outcome most of our bathtub installation clients in those neighborhoods end up choosing.

Four Ways to Convert a Tub to a Shower

1. Acrylic or solid-surface conversion

A molded base plus wall panels, no grout to maintain, three to five days on site. This is the right call for rental units, basement baths, condos with slab restrictions, and anyone who needs the bathroom back in a week. It looks like what it is, but it is watertight and it is fast.

2. Tiled walk-in shower in the same footprint

The most common conversion we build in Bethesda. A mud-set or foam pan, a sheet or liquid waterproofing membrane, porcelain wall tile, a recessed niche, and a semi-frameless glass panel and door. Same footprint, same drain, dramatically different room.

3. Tiled walk-in with frameless glass and upgraded fixtures

The same build with heavy frameless glass, a thermostatic valve, a rain head plus a hand shower on a slide bar, a full-height niche, and often a bench. See our shower enclosure page for glass thickness and hardware options, since the glass is usually the single largest line item at this tier.

4. Curbless or roll-in accessible conversion

The floor structure is modified so the shower floor sits flush with the bathroom floor, with a linear drain, a 36-inch clear entry, solid blocking for grab bars, and a hand shower reachable from a seat. This is what we build for Montgomery County clients who intend to stay in the house, and it is the version that may qualify for the county tax credit described below.

Where the Money Actually Goes

A single range is easy to distrust, so here is the same tiled conversion broken into the lines that appear on our quotes. These are Bethesda-area figures for a standard 60-by-30 alcove with the drain staying put.

Figures are 2026 Bethesda-area planning estimates for a standard alcove conversion with the drain staying in place. Your quote depends on in-home measurements, the condition behind the existing tile, and the finishes you select.

Permits, Code, and WSSC in Montgomery County

This is the part that catches homeowners here, and it is worth understanding before you sign anything. A tub to shower conversion in Montgomery County involves two agencies, not one.

The building alteration permit comes from the Montgomery County Department of Permitting Services (DPS), now at 2425 Reedie Drive in Wheaton. Any electrical work, a GFCI receptacle, a wet-rated light inside the shower, or a replacement exhaust fan, is a separate DPS electrical permit.

The plumbing permit does not come from the county. In Montgomery and Prince George's counties, WSSC Water issues plumbing and gasfitting permits, and WSSC regulations require that most plumbing work be performed by a WSSC-licensed plumber or gasfitter. Converting a tub means a new mixing valve and a drain change, so the plumbing permit applies even when you keep the same footprint. If a contractor tells you a conversion needs no plumbing permit because nothing moved, that is a red flag.

Plan two to four weeks for permitting before demolition. DPS aims to complete code review in about 17 days for a complete application, and WSSC reviews on its own schedule. DPS adopted the 2021 International Code Council family of codes in December 2024, with a transition window for applications filed before the end of March 2025.

The code points that actually shape a conversion:

• • The shower floor needs at least 1,024 square inches of area with a minimum 30-inch dimension in every direction. A 60-by-30 alcove clears this comfortably, which is another reason the standard Bethesda footprint works so well.
• • The shower needs a pressure-balancing or thermostatic mixing valve limited to 120 degrees. A tub spout diverter valve does not satisfy this on its own.
• • Wet walls need code-compliant backer and waterproofing, not the old greenboard that came out of the wall.
• • The bathroom needs mechanical ventilation or an operable window, and the fan has to duct to the outside rather than into the attic.
• • Rough-in inspections happen before the walls close. Tiling over un-inspected plumbing is the single most expensive mistake on this list.

Two local wrinkles. If you are in a condo or a managed townhome community around Pike & Rose, Grosvenor, or downtown Bethesda, the building will want board approval and your contractor's certificate of insurance, and will often restrict work to weekday hours. Start that the same week you apply for permits. And if your home sits in a designated historic district such as Chevy Chase Village, Garrett Park, or parts of Kensington, the Historic Preservation Commission reviews exterior work, so a purely interior bathroom conversion generally does not need a historic area work permit. Confirm it before demolition anyway.

We pull and manage both permits on every project and schedule the inspections, which is most of why our Bethesda clients do not have to learn any of the above.

The Design for Life Tax Credit Most People Miss

Montgomery County runs a program called Design for Life, administered through DPS, that gives property tax credits for accessibility retrofits. It is aimed at exactly the features an accessible shower conversion involves: a roll-in or curbless entry, grab bars, a wider bathroom door, and comfort-height fixtures.

As the county describes it, adding a single qualifying feature costing between $500 and $2,500 earns a credit of 50 percent of the cost. Meeting the county's full visitability standard earns $3,000, and meeting the livability standard earns $10,000, applied against your property tax bill up to an annual cap. Amounts and eligibility rules change, so confirm the current figures with DPS before you build a budget around them.

The practical advice: raise it before you file. The county wants the accessibility features identified with the permit application, not discovered after the tile is grouted. If aging in place is any part of why you are converting the tub, tell your designer at the first meeting.

Local Details That Change the Design

Hard water is the number one complaint we hear a year later. WSSC water runs hard enough that a clear frameless glass panel shows spotting quickly, and the same minerals leave a film on dark tile near the head. Three things help: specify low-iron glass with a factory-applied hydrophobic coating, choose a textured or fluted glass panel that hides spotting far better than clear glass, and keep a squeegee in the shower. Clients who do all three stop noticing the water.

Matte black is the most requested finish here and the least forgiving. It shows water spots and damages under the wrong cleaner. In a primary bath used by two adults it is fine. In the kids' hall bath, brushed nickel stays looking new with less effort.

Ventilation matters more after a conversion than before it. Summer humidity in the DMV is heavy, and an open walk-in shower puts far more moisture into the room than a tub with a curtain did. If the existing fan is a builder-grade 50 CFM unit venting into the attic, replace it and duct it through the roof or gable. Nearly every mold complaint we get called about after somebody else's conversion is a ventilation problem, not a waterproofing problem. It is worth coordinating with your lighting plan while the ceiling is open.

Large-format tile makes a small Bethesda bath read larger. Twelve-by-24 porcelain on the wet walls gives you a fraction of the grout lines of the original 4-inch tile, and less grout is both less visual noise and less cleaning. Pair it with a small mosaic on the shower floor, where the extra grout lines buy you slip resistance.

Plan the door swing before you fall in love with a door. In a 5-by-8 hall bath, a hinged glass door frequently will not clear a 30-inch vanity. The usual fixes are a fixed panel with an open walk-in return, or a sliding door on a track. Deciding this early also affects where the vanity can go.

Put the niche opposite the valve. Reaching through cold spray for the shampoo is a daily annoyance that costs nothing to avoid. In a 60-inch alcove there is nearly always a free stud bay on the back wall.

Project Timeline, Day by Day

This is a realistic schedule for a tiled conversion in a Bethesda hall bath, counted from the first day on site. Add two to four weeks of permitting in front of it.

• • Day 1: floor and stair protection, demolition, cast-iron tub cut out and hauled away, old backer removed to the studs.
• • Days 2–3: plumbing rough-in, mixing valve set to the correct depth for the finished tile plane, drain converted, blocking added for grab bars and a bench while the wall is open.
• • Day 3 or 4: rough-in inspection. Nothing closes until this passes.
• • Days 4–6: backer board, waterproofing membrane, corners and pan, then a 24-hour flood test on the pan.
• • Days 6–9: wall and floor tile set, cured, then grouted.
• • Day 9 or 10: the glass shop templates the finished opening. This is where schedules stretch: most local shops need seven to ten days from template to installation, and no honest contractor can compress it.
• • Days 12–16: glass installed, fixtures and trim set, patching and paint, final inspection.

Call it two to three weeks on site for a tiled shower, three to five days for an acrylic conversion. If a bid promises a tiled conversion in under a week, ask when they intend to flood test the pan and when the glass gets templated.

Mistakes We See Most Often

• • Removing the last tub in a three-bedroom family house without thinking through resale
• • Tiling over the existing surround backer instead of replacing it, when the reason the old tile was loose is that the backer is already wet
• • Buying the valve after demolition, when the valve determines the rough-in depth and has to be on site first
• • Skipping the 24-hour flood test on a new pan to save a day
• • Templating the glass before the tile is grouted and cured, because the opening moves
• • Closing the wall without blocking for grab bars, which means opening finished tile later
• • A curbless entry with too little floor slope or too short a linear drain, so water migrates onto the bathroom floor
• • Assuming the county issues the plumbing permit, then finding out mid-project that WSSC never reviewed it
• • Reusing an undersized exhaust fan that vents into the attic

Frequently Asked Questions

Working With a Local Team on This

A tub to shower conversion looks like a small project and behaves like a plumbing, waterproofing, tile, and glass project stacked in sequence, each one dependent on the last. iDesign Interior Solutions has done this across Bethesda, North Bethesda, Rockville, Chevy Chase, Potomac, Silver Spring, and the wider DMV for more than two decades, with over 2,700 completed projects. We know how these houses are plumbed, we pull both the DPS and WSSC permits, and we sequence the glass so the bathroom is not sitting open for a week waiting on a template.

If you are weighing a conversion against a full remodel, our bathroom remodeling page covers the wider scope, and our bathroom design ideas guide is a good place to gather the look before you talk numbers.