November 9, 2025

Tub-to-Shower Conversions in Dover, NH: 5 Missteps to Steer Clear Of

Replacing a tub with a shower is one of the most practical upgrades you can make in a Dover home, especially in older New England capes and colonials where bathrooms run tight and daily routines favor quick showers. Done well, a bathtub-to-shower conversion can improve safety, free up floor space, and lift resale appeal. Done poorly, it can leave you with moisture problems, awkward layouts, and expensive rework. I have walked homeowners through both outcomes. The difference comes down to planning, details, and honest constraints.

Below are the five missteps I see most often when converting a bathtub to a shower in Seacoast-area homes, with field-tested guidance on how to avoid them.

Misstep 1: Ignoring Structure and Drainage

A tub occupies a generous footprint but demands little slope. A shower pan is the opposite. The drain location, joist direction, and existing trap all dictate how cleanly you can execute a tub-to-shower conversion. In Dover’s housing stock, many first-floor baths sit over basements with old-growth joists and notched or sistered sections from prior renovations. I have opened floors to find a 1.5-inch drain on a long run, which is undersized for most modern showers. Altering structure or reworking plumbing after tile is down is a painful change order.

The smart move is to open a small exploratory section before you order any fixtures. Verify the drain size, measure joist depth and spacing, and map the path to the main stack. Ideally, upsize to a 2-inch drain and center it within the new shower footprint to ensure even slope and faster evacuation. If joists run perpendicular to the preferred drain line, expect either a low-profile pan that accommodates an offset drain or limited, engineered notching along with proper reinforcement. In the many homes with finished basements under the bath, plan the ceiling patch below as part of the job, not an afterthought.

Misstep 2: Underestimating Waterproofing

New England winters and spring thaws keep indoor humidity high. A shower enclosure must be a sealed envelope, not a suggestion. Skipping a continuous waterproofing membrane behind tile, relying on green board alone, or mixing incompatible products invites mold and loose grout within a year or two. I have seen beautiful tile installations over moisture-resistant drywall fail simply because the corners and niches were never banded.

Choose a system and stick with it. Cement board plus a liquid-applied membrane, or foam backer panels with integrated seams, both work when installed correctly. Lap seams at least two inches, use preformed inside and outside corners, and flood test the pan for a full 24 hours before setting tile. If you are using a prefabricated base, do not skip a mortar bed under the pan unless the manufacturer says otherwise. In homes with exterior walls on the north side, consider a vapor-smart approach to avoid trapping moisture in the wall cavity. Tile is a finish, not a waterproofing layer, so give it a resilient substrate.

Misstep 3: Designing Without Users in Mind

A sleek render might impress, but your knees and shoulders have the final say. Households in Dover often span generations. The shower should flex for an older parent visiting from Portsmouth, a teenager rushing to school, and a weekend gardener rinsing off after tackling leaves. A common mistake is standardizing everything at one height and calling it done.

Think carefully about entry and reach. For larger footprints, a curbless shower with a gentle slope simplifies access, but it demands precise subfloor work and a linear drain set parallel to the entry or back wall. For traditional curbed showers, keep the threshold around 3 inches high to balance splash control and ease of step. Niches should sit between 42 and 50 inches off the finished floor in most cases, and a second lower niche helps for shaving or seated use. If you have the stud depth, add 2x8 blocking now for future grab bars, even if you do not plan to install them this year. As for doors, pivot doors need room to clear fixtures, while sliders require a true opening and a square pan. In compact Dover bathrooms, I often recommend a frameless slider and a 30 to 36 inch opening to keep circulation smooth.

Misstep 4: Overlooking Ventilation and Heat

Shower conversions often shrink the open air volume in the room by closing off a tub alcove. Steam lingers longer. If your bath fan is rated at 50 CFM and wired to a switch that turns off when you exit, you will invite condensation on windows and paint. I have measured humidity spikes over 70 percent in similar setups, then found paint curling behind mirrors and mildew in corners.

Aim for at least 80 to 110 CFM for a small to mid-size bath, and more if you have a long or complex duct run to an exterior wall or roof. Upgrade the duct to smooth-walled metal and keep runs short with gentle turns. A humidity-sensing timer that runs the fan for 20 to 30 minutes after a shower makes a noticeable difference. On the comfort side, radiant floor heat or a low-profile wall panel heater takes the edge off cold tile in January and doubles as a quick dryer for a wet floor. If you opt for glass doors, treat the glass or choose patterned options that disguise water spots, since Seacoast water can leave mineral marks without frequent squeegeeing.

Misstep 5: Chasing Trend Over Durability

Matte black fixtures, herringbone tile, and ultra-large format panels have their place. They also have maintenance realities. Hard water shows on dark finishes. Narrow grout joints with aggressive patterns can chip if the substrate is not dead flat. A tub-to-shower conversion should favor materials that hold up to daily use in a coastal climate, not just look sharp for listing photos.

This is where honest trade-offs pay off. I often recommend a balanced palette: a solid-surface or stone-composite base for stability and easy cleaning, 12-by-24 porcelain for walls to minimize grout, and a slip-resistant rating of at least DCOF 0.42 on floors. Polished nickel or brushed stainless stands up well to water spots. If you love real stone, reserve it for a feature wall away from the main splash zone and seal it on a schedule. For grout, spend the extra on epoxy or high-performance cement grout to cut down on maintenance. Glass thickness matters too; 3/8 inch tempered glass resists flexing and rattling in older homes with slightly out-of-square framing.

What a Realistic Timeline Looks Like in Dover

Even straightforward tub-to-shower conversions require coordination. For a best bathtub replacement options typical alcove, expect one to two days for demo and rough inspection, one day for plumbing and drain upgrades, a day for pan setting or mud bed, one to three days for walls depending on tile layout, then glass templating if doors are custom. Lead time for glass can run 10 to 15 business days. All told, you are often looking at two to three weeks from first hammer to final squeegee, with longer timelines if you are moving walls, reworking a window, or addressing structural surprises. Winter work adds the wrinkle of curing times in cooler spaces, so plan for temporary heat.

Cost Ranges You Can Bank On

Every house varies, but in the Seacoast market a basic tub-to-shower conversion using a quality acrylic or composite base, waterproof wall panels, upgraded 2-inch drain, and a stock glass door typically falls in the 8,500 to 12,000 dollar range. A tile surround with a custom niche, epoxy grout, upgraded fixtures, and custom glass usually lands between 12,000 and 18,000 dollars. Curbless entries, linear drains, large-format porcelain, and radiant heat can push the project to 20,000 dollars and beyond. These figures assume no major structural remediation. Hidden damage around an old tub spout or window can add 1,000 to 3,500 dollars quickly, which is why a thorough site assessment up front saves headaches later.

A quick pre-project checklist

  • Verify drain size and route, and plan for a 2-inch drain whenever feasible.
  • Choose a complete waterproofing system and schedule a 24-hour pan flood test.
  • Confirm door swing or slider clearance with real measurements, not guesses.
  • Upgrade ventilation and add a timed or humidity-sensing control.
  • Add blocking for future grab bars and choose slip-resistant floor materials.

When to Bring in a Pro

Handy homeowners can tackle parts of a tub-to-shower conversion, like demolition or painting. The riskiest steps, the ones that can cause lasting problems, are plumbing alterations, pan installation, and waterproofing. If your bathroom sits over finished space, or if your home is in one of Dover’s older neighborhoods with mixed-generation plumbing, it pays to hire a contractor who has converted dozens of similar baths and is comfortable navigating permits, inspections, and the quirks of century homes. The right pro will not push you toward a catalog package, but will help you weigh the trade-offs with a clear eye.

Plan for structure and drainage, commit to proper waterproofing, design for the way you live, manage humidity, and choose materials that endure. Do those five things, and your tub-to-shower conversion will serve you well through winters, renovations, and resale alike.


Jeff Coleman has been serving home owners in various roles over the last 25 years. In 2020 Jeff started Cloud 9 Tubs LLC due to his frustration with the sales tactics and poor customer service he experienced working for larger companies. He also has a passion for bathroom safety as most falls in the home happen in the bathroom and his own grandmother passed after experiencing a fall. His focus is not just on updating bathrooms but in providing a safer and more accessible bathing experience and creating a better quality of life for his customers. Cloud 9 Tubs LCC stands apart from their competitors in the emphasis that they put on the customer experience. Jeff takes great pride in the personal service that he and his team provide.