What size water heater do I need after adding a bathroom during a renovation in NB?

Adding a bathroom typically requires upgrading to the next water heater size up from your current unit. Most NB homes with 2-3 bathrooms need a 50-60 gallon tank or a tankless unit rated for 3-4 simultaneous fixtures.

The standard rule is 10-15 gallons of hot water storage per person in the household, but bathrooms are the biggest hot water users. A standard bathtub uses 25-30 gallons to fill, while a 10-minute shower consumes 15-25 gallons depending on the showerhead flow rate. Adding that extra bathroom means potential simultaneous use — someone showering while dishes are being washed or laundry is running.

Current NB water heater sizing typically breaks down as follows: 40 gallons for 1-2 people in a 1-bathroom home, 50 gallons for 2-3 people with 2 bathrooms, 60-80 gallons for 4+ people with 3+ bathrooms. If you're currently running a 40-gallon unit and adding a second bathroom, upgrading to 50-60 gallons makes sense. If you have a 50-gallon unit and adding a third bathroom, consider 60-80 gallons or switching to tankless.

Tankless water heaters are increasingly popular in NB renovations because they don't take up basement floor space and provide unlimited hot water. A whole-house tankless unit costs $2,500-$4,500 installed compared to $1,200-$2,000 for a tank unit, but the space savings and endless hot water appeal to many homeowners. Tankless units require adequate gas supply (if gas-fired) and may need electrical upgrades for electric models.

NB's cold incoming water temperature affects sizing calculations. Our groundwater enters homes at 6-8°C in winter compared to 12-15°C in warmer climates. This means your water heater works harder to reach the 60°C output temperature, effectively reducing capacity. Size up accordingly — what works as a 40-gallon unit in warmer regions may need to be 50 gallons in New Brunswick.

Installation requires TSANB-licensed plumbers and gas fitters. Water heater installation involves gas lines (if applicable), water connections, venting, electrical connections, and pressure relief valve installation. This is not DIY work. The installation cost runs $500-$1,200 depending on complexity, venting requirements, and whether gas lines need upgrading. Factor this into your bathroom addition budget.

Consider your renovation timeline carefully. If you're adding a bathroom as part of a larger renovation, coordinate the water heater upgrade early in the project. Running out of hot water mid-renovation when contractors need to clean up creates delays. Many contractors appreciate adequate hot water for cleanup and testing new fixtures.

Energy efficiency matters in NB's climate. Look for ENERGY STAR certified units with high efficiency ratings. Tank units should have thick insulation and electronic ignition (for gas models). Heat pump water heaters work well in heated NB basements, extracting heat from basement air while providing hot water. They cost more upfront ($3,000-$4,500 installed) but can cut water heating costs by 50-60%.

Need help finding a TSANB-licensed plumber for your bathroom addition and water heater upgrade? New Brunswick Renovations can connect you with experienced local professionals who handle both the plumbing rough-in and water heater installation as part of your project.

---

Looking for experienced contractors? The New Brunswick Construction Network connects homeowners with qualified professionals:

• Thirty Four Renovations
• Gionetterenovations