How to Choose the Right Water Heater Size for Your Growing Family

When your family expands, so do your household’s hot water needs. Whether you’ve welcomed a new baby, have teenagers taking longer showers, or have relatives visiting for the holidays, the water heater that once worked for your home may start falling short. As a Tulsa homeowner, choosing the right size water heater is crucial to keep everyone comfortable and avoid surprises like cold showers or high utility bills. At Colossal Plumbing, we’ve helped families across Tulsa, Jenks, Broken Arrow, and beyond select and install the perfect water heater for over two decades. Here’s what you need to know to make the best decision for your growing family.

Why Water Heater Size Matters

Choosing the proper water heater size is about more than comfort. If your water heater is too small, you may run out of hot water during peak times—think back-to-back morning showers or when company comes to stay. An undersized heater also works harder to keep up, which can shorten its lifespan and increase energy bills. On the other hand, a water heater that’s too large wastes energy, costing you more every month. The right size balances your family’s needs with efficiency and reliability.

Key Factors to Consider

1. Family Size and Daily Routine

Think about how many people live in your home and your day-to-day routines. The number of showers, baths, loads of laundry, and dishes determines your peak hot water demand. For example, a family of four typically needs more hot water than a couple—but if you have small children or teenagers, your usage may spike even more.

2. Peak Hour Demand

Your “peak hour demand” is the busiest 60-minute period in your home for hot water use. Add up the gallons of hot water used during that time. For example:

• A shower uses 10-15 gallons
• Running a load of laundry: 7-10 gallons
• Washing dishes by hand: 4-6 gallons It’s easy to see how your needs add up quickly, especially with a larger family.

The right water heater size should meet your peak hour demand without running out or causing unnecessary wait times.

3. Type of Water Heater: Tank vs. Tankless

Tank water heaters store a set amount of hot water, typically ranging from 30 to 80 gallons. Tankless (on-demand) water heaters heat water as you need it, offering endless hot water and energy savings. Families with high simultaneous usage, like multiple showers at once, may benefit from multiple tankless units or a larger storage tank.

4. Future Planning

If your family is growing, it’s wise to anticipate changes. Are you planning more children? Do you frequently host relatives over the holidays? Consider future needs to avoid another upgrade soon.

How to Calculate the Right Size Water Heater

For tank water heaters, match your “first hour rating” (FHR)—how much hot water it can deliver in one hour—to your peak hour demand. Here’s a quick estimate for families:

• 1–2 people: 30–40 gallons
• 3–4 people: 40–50 gallons
• 5+ people: 50–80 gallons

For tankless water heaters, consider the flow rate (gallons per minute, or GPM) needed to run your peak appliances at once. For example, two showers running at the same time plus a dishwasher may require a tankless unit with a higher GPM output or even multiple units.

Local Considerations for Tulsa Homes

Tulsa’s seasonal temperature swings can also affect water heater performance, especially if cold groundwater lowers output in winter months. Colossal Plumbing’s local experts account for these Oklahoma-specific factors when recommending your ideal unit, ensuring you have reliable hot water year-round.

When to Call a Professional

While online calculators and rough estimates are helpful, every home is different. Factors like plumbing layout, fixture upgrades, and efficiency goals require an expert eye. A licensed, local plumber can perform an in-depth analysis and recommend solutions tailored to your family’s lifestyle, water demand, and budget.

Ready for Endless Comfort? Call Colossal Plumbing

Don’t let an undersized water heater leave your growing family in the cold. The team at Colossal Plumbing has been Tulsa’s trusted water heater experts for over 20 years. We’ll help you assess your needs, recommend the perfect size and type for your household, and ensure a seamless, code-compliant installation with minimal disruption. If you’re ready for reliable hot water—no matter how big your family gets—contact Colossal Plumbing today for a free consultation. Let us handle your hot water needs while you focus on what matters most: enjoying your home and family. Call or visit www.colossalplumbing.com to schedule your assessment!