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Sample Project

Project: Green Bathroom Remodel

While You're Updating the Fixtures, Don't Forget about Water, Moisture, and Ventilation Issues

Choose durable green materials

Bathrooms are often among the smallest rooms in the house, but they are rich with opportunity in a green remodel. No matter what the design goals for the renovation, two practical essentials are managing water and steam and selecting durable materials that are made to handle what’s often a tough environment.

Updating the bathroom's ventilation can retard mold and mildew growth.

There are several reasons a client may decide to remodel a bathroom. The most common are a desire to upgrade the fixtures in the room, to fix leaks and water damage, and to increase or reconfigure the room's floorplan.

Active water leaks and a lack of mechanical ventilation should be among the top priorities for correction. When changes are more than skin deep, improving the building’s envelope with an effective air barrier, vapor retarder and adequate insulation all should be part of the plan. Because humidity levels tend to be very high in a bathroom, extra care should be taken to minimize the risk of moisture accumulation and condensation in wall cavities.

While addressing those issues it's important to open a discussion about bathroom ventilation and how a proper fan system can improve the air quality and the longevity of not just the bathroom but the whole house by exhausting moist warm air that can promote mold and mildew growth.

Are there mechanical, electrical or structural problems?

The project may require extensive rewiring and plumbing. If that’s the case, consider how changes in the bathroom might be integrated with other remodeling projects under consideration and plan accordingly.

Does someone in the house have health or mobility problems to consider?

Designing a new bathroom with the needs of less mobile people in mind can let older homeowners stay in the house longer. Taller toilets that meet ADA guidelines, sinks that are accessible to wheelchairs, framing that accommodates grab bars and curb-less showers all can be valuable features.

Is the bathroom big enough?

Using what space is available is the least expensive option. Enlarging the bathroom by expanding into an adjacent but underused closet or spare room would be a next step, and building a new addition an expensive last resort. The goals should be to minimize the amount of remodeling that’s required, saving money and materials.

More About Bathroom Remodeling


New fixtures should use as little water as possible. Choose low-flow showerheads, high-efficiency toilets and water-conserving aerators on sink faucets. If a water heater needs replacement, pick a high-efficiency model and consider a tankless heater or a hot-water circulation option if the main water heater is some distance away from the bathroom. Include a plumbing access door for shower valves.

Water management

Be sure your choice for tub and shower surroundings sheds water effectively and is easy to clean. Never use gypsum drywall (even the moisture-resistant variety) under tile in a shower or around the tub.


Install a quiet fan of appropriate capacity and vent it to the outside. Consider more than one fan if the bathroom is large, and timers or humidity-sensing switches to ensure that the fan runs long enough after a bath or shower.

Wall, ceiling and floor finishes

Use durable materials that are not unduly affected by moisture. Consider tile made from recycled materials, and use paints, finishes, grout and caulk that are low in volatile organic compounds (low-VOC). Reuse existing subflooring and flooring where possible. Avoid carpeting.


Avoid cabinetry made of particleboard or medium-density fiberboard; these will not tolerate moisture. Install environmentally friendly countertops.

Image Credits: Julia Jandrisits/REGREEN, Debra Lynn Dadd/REGREEN

Content By GBA

A moldly oldie goes new and green

With a 5-by-8-foot bathroom combining 1960s décor with original features from 1940, the homeowners hoped to renovate eventually, when they could budget it. They ended up acting sooner after discovering that mold in the bathroom was the cause of their recent breathing and sleeping problems. A house inspection team uncovered the mold infestation and recommended taking the bathroom down to the studs for full remediation. The couple took advantage of the problem to create a visually appealing, nontoxic and mold-resistant bathroom within the existing space. They tailored the bathroom to meet their needs while also keeping in mind future resale.

Provide good ventilation and durable, nontoxic finishes

The old bathroom had no ventilation, causing consistently high humidity, and its galvanized steel pipes had corroded, saturating the floor around the tub and toilet areas and damaging the floor and subfloor. The couple’s highest priority was to create a durable bathroom that would remain mold-free. This meant proper detailing and rethinking plumbing, ventilation, and finishes. They also wanted to include as many environmental features and materials as their budget and the small space would allow. They chose a bathroom theme celebrating water and nature as works of art, and a style befitting an average suburban home, making it suitable for resale.

Key Systems

  • HVAC
  • Ventilation ducted to outdoors
  • Plumbing
  • Low-flow fixtures for sink, toilet, and shower
  • Low-flow showerheads designed for efficiency (not retrofitted with flow-restrictors)
  • Lighting
  • Natural lighting provided by skylight over shower
  • Finishes
  • Tile floor and tile walls throughout the bathroom
  • Durable marble baseboard
  • Breathable (natural-colored) clay plaster finish
  • Nontoxic grout and grout sealer
  • Waterproof detailing

Compromises cut costs but not priorities

The homeowners found they had to make some compromises to meet their budget for the project. Although they used nontoxic finish products and prioritized durability in aspects such as plumbing and tiling, they passed on other, less affordable features, such as recycled-content tile. Because Larry performed so much of the actual work, he was less prepared for the unknown than a professional may have been. While mixing the mortar for the tiled shower pan, for example, Larry discovered—too late—that the instructions he had didn’t match the included illustrations.

Team and processes

Taking one year to complete the project, the couple hired skilled contractors to do the mold remediation, plumbing, and electrical work but did the finish work themselves. An extra toilet in the house and a shower in their rental property nearby gave them the flexibility to take whatever time they needed. They made sure to research correct tile shower installation to avoid future leaks. Larry first installed cement backerboard underlayment on walls and floor instead of paper-faced greenboard, which is cheaper but cannot tolerate the amount of moisture generated in a bathroom). He then used nontoxic, thin-set mortar to hold the tile and applied nontoxic grout and grout sealer to finish the job. Their research on tile shower installation led Larry to follow the methods and materials of Ontario Tile Setters (

  • Location: Clearwater, Florida
  • Homeowner and Environmental Consultant: Debra Lynn Dadd
  • Homeowner and Amateur Builder: Larry Redalia
  • Area affected: 40 ft2

Debra and Larry had not budgeted for this emergency bathroom remodel. Although their insurance paid for basic mold remediation,it did not cover the cost of updating fixtures, furnishings or finishes. By undertaking much of the design and construction themselves, the homeowners were able to budget more for materials and consider products&rsquop; durability and style, not just affordability. They also shopped architectural salvage yards to acquire, at lower cost, quality materials such as handmade tile.

  • ASID