How to Design a Sustainable Bathroom

Bathrooms are one of the most-used spaces in a home, and a bathroom renovation can transform an essential part of your day. When we moved in, our bathroom was barely functional - the toilet barely worked, and the hot water in the shower was lukewarm as best.

For me, sustainable bathroom design requires thinking about the big picture and the little details. It’s about asking: What can I reuse? How can I save water and energy? Which materials will last for decades instead of just a few years?

If you’re planning an eco-friendly bathroom remodel, here are some practical ideas that will leave you with a space that is sustainable, healthy, and timeless.

Start with What You Already Have

The most sustainable material is the one that’s already in your home. Before you start pulling out tile or ordering a new vanity, take stock of what can stay.

Vanities and cabinets can often be refinished or painted with a low-VOC paint rather than replaced. Originally, I planned to sand and refinish our cabinet, but after testing one door, I realized that we would need to repaint it.

Before

After

Bathtubs can be resurfaced instead of tossed into a landfill. We kept our tub–it was in perfectly good condition, even though we would have preferred a built-in, tiled sub.

Tile and hardware can sometimes be salvaged, either reused in your bathroom or passed along to a local building salvage nonprofit. We gave away our old vanity hardware to someone in our local Buy Nothing group. Not only does reuse reduce waste, it saves money that you can put toward higher-impact upgrades like water-saving fixtures or energy-efficient lighting.

Save Water with Smart Fixtures

Bathrooms are where we use the most water indoors, so swapping out fixtures is a powerful tool to conserve water. Look for EPA WaterSense labeled toilets, showerheads, and faucets.

Toilets: Look for EPA WaterSense toilets that use 1.28 gallons per flush or less. A dual-flush model can save thousands of gallons per year in a family home.
Showerheads: EPA WaterSense showerheads use 1.8 gallons per minute or less.
Faucets: EPA WaterSense faucets use 1.2 gallons per minute or less, and you can find fixtures that use as little as .5 gallons per minute. The Kohler Castia faucet is one example of a faucet that is .5 gallons per minute.
Piping: Avoid plastic piping options such as PVC or PEX; choose copper and cast iron.
Plumbing upgrades are one of the most immediate and measurable ways to make a bathroom more sustainable.

Choose Materials That Are Durable, Non-Toxic, and Sustainable

Bathrooms are subject to a lot of moisture, so you want to make sure that materials will hold up and will have a long life. You also want to consider materials that are non-toxic, local, and sustainable..

Tile: Recycled-content porcelain or ceramic tile is widely available, and it’s even better if it’s local. There are several tile makers here in Portland who use natural, non-toxic glazes.
Countertops: A natural stone is my favorite countertop finish to use, but quartz can be a good option as well. There are some health concerns for quartz fabricators, so make sure to educate yourself about the issue and verify that your supply has appropriate precautions in place.
Paints & finishes: Always choose low- or zero-VOC paints and sealants.
Flooring: Local or recycled tile is always a great choice. FSC or reclaimed wood could be an option, but I wouldn’t recommend it in a full bathroom due to the moisture. We used leftover black slate tile from a friend.

If you’re choosing new finishes, try to avoid chasing trends. A classic material palette will feel fresh for decades and keep you from wanting a remodel again in just a few years.

Pay Attention to Energy Efficiency

Water heating alone makes up about 18% of home energy use. Lighting, ventilation, and even heating can all be designed with efficiency in mind.

Lighting: LED fixtures are a must. Focus fixtures where you need them - over the shower and at the vanity. Consider secondhand fixtures or eco-friendly brands.
Ventilation: Install a high-efficiency bath fan with a timer to keep humidity under control without wasting energy. Bonus points if it also integrates a light.
Heating: If you need extra heat in the bathroom, radiant floors can be a good option, and are about 30% more efficient than electric baseboards.

If you’re remodeling, this is a great time to add insulation behind bathroom walls, ceilings, and floors. Improvements here can reduce energy loss for the whole home.

Let in Natural Light

A bathroom with good natural light and ventilation feels healthier and more calming. If your layout allows, consider adding a window, enlarging an existing one, or even adding a skylight or solar tube.

Daylight reduces the need for artificial lighting during the day and helps tune our circadian rhythms.

Think About Longevity

The most sustainable bathroom is one you don’t have to remodel again anytime soon. That means investing in quality where it matters most, while keeping decorative elements flexible and easy to change.

Timeless design doesn’t have to mean boring. Natural materials, clean lines, and classic color palettes provide a foundation that can adapt to your style for years to come.

Add Human Comfort and Well-Being

At the end of the day, sustainability isn’t just about numbers. A bathroom should be functional, but it can also be a retreat that makes you feel good.

Add living plants if there is enough light. Plants love the humidity in bathrooms.
Use natural textures, like linen, wood, and stone, for warmth and balance.
Use warm toned lights - they’re more calming and inviting.

Final Thoughts

Designing a sustainable bathroom is less about following strict rules and more about making intentional choices. Reuse what you can, invest in water- and energy-saving systems, choose healthy materials, and think long-term.

With these steps, you can create a bathroom that reduces your environmental footprint, saves you money over time, and feels like a true sanctuary in your home.