A home renovation is the perfect opportunity to upgrade systems that most homeowners take for granted — and your water heater is one of the most impactful. Whether you’re remodeling a bathroom, finishing a basement, or giving your entire home a refresh, selecting the right water heater affects everything from your daily comfort to your monthly energy bills and property value.
With so many options on the market, choosing the right one can feel overwhelming. Here’s everything you need to know to make the right decision for your renovation.
Step 1: Understand Your Household’s Hot Water Demand
Before looking at specific models, calculate how much hot water your household actually uses. This depends on:
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Number of people in the home — A family of four uses significantly more hot water than a couple.
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Simultaneous usage — Do multiple showers, the dishwasher, and the washing machine run at the same time?
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Appliance requirements — Some appliances, like high-efficiency washing machines, need specific water temperatures.
As a general rule:
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1–2 people: 30–40 gallon tank OR a low-flow tankless unit
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3–4 people: 40–50 gallon tank OR a medium-capacity tankless unit
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5+ people: 50–80 gallon tank OR a high-capacity tankless or dual-unit system
Getting this wrong is one of the most common renovation mistakes. An undersized water heater means cold showers; an oversized one wastes energy and money.
Step 2: Tank vs. Tankless — Which One Is Right for You?Traditional Tank Water Heaters
The classic 40- or 50-gallon tank remains the most popular choice for a reason. These units store a reservoir of hot water and keep it ready for use.
Pros:
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Lower upfront cost (400–400–1,200 installed)
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Simple installation with no major electrical or gas line upgrades
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Reliable technology that’s been proven for decades
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Works well for households with moderate, predictable usage
Cons:
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Less energy-efficient due to standby heat loss
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Limited hot water supply — once the tank is empty, you wait
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Takes up floor space (usually in a basement, garage, or utility closet)
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Shorter lifespan (10–15 years)
Tankless (On-Demand) Water Heaters
Tankless units heat water directly as it flows through, providing an endless supply of hot water.
Pros:
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22–34% more energy-efficient than tank models
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Unlimited hot water — perfect for large families or frequent guests
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Compact size mounts on a wall, freeing up valuable floor space
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Longer lifespan (20+ years)
Cons:
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Higher upfront cost (1,500–1,500–3,500 installed)
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May require upgraded gas lines, venting, or electrical capacity
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Flow rate limitations — you may need to stagger hot water usage
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More complex installation, especially in older homes
Which to choose? If your renovation involves significant plumbing work or if you’re already opening up walls, the higher installation cost of a tankless unit is easier to absorb. If you’re on a tighter budget and have adequate space, a high-efficiency tank model delivers excellent value.
Step 3: Consider Your Fuel Type
Your energy source heavily influences both operating costs and installation complexity.
Fuel TypeBest ForConsiderationsNatural gasHomes with existing gas linesLower operating cost, requires proper ventingElectricHomes without gas hookupHigher operating cost but simpler installationPropaneRural homes without natural gasSimilar to natural gas but higher fuel costHeat pumpWarm climates (garages, basements)Most efficient option, requires more spaceSolarSun-rich states with incentivesHighest upfront cost, best long-term savings
If you’re doing a full home renovation, this is the time to add a gas line or upgrade your electrical panel if needed. Making these changes after the walls are closed is far more expensive.
Step 4: Size Matters — Get the First-Hour Rating Right
For tank water heaters, the key metric is the First-Hour Rating (FHR) — the amount of hot water the heater can supply in an hour starting with a full tank. You’ll find FHR on the Energy Guide label of every tank water heater.
To estimate your FHR needs:
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Shower: 10–15 gallons per person
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Bath: 15–20 gallons
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Dishwasher: 6–10 gallons per load
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Washing machine: 15–30 gallons per load
Add up the peak hour usage in your household. For a family of four with morning showers and the dishwasher running, you typically need an FHR of 60–80 gallons.
For tankless units, look at the gallons per minute (GPM) rating. A standard shower uses 1.5–2.5 GPM. If you plan to run two showers plus the dishwasher simultaneously, you need a unit rated for 5–7 GPM.
Step 5: Energy Efficiency and Long-Term Savings
Modern water heaters come with Energy Factor (EF) or Uniform Energy Factor (UEF) ratings. Higher numbers mean better efficiency.
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Standard gas tank: UEF 0.60–0.70
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High-efficiency gas tank: UEF 0.70–0.85
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Electric tank: UEF 0.90–0.95
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Tankless gas: UEF 0.82–0.98
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Heat pump: UEF 2.00–4.00 (most efficient)
While a higher-efficiency unit costs more upfront, the energy savings accumulate. Over a 10-year period, a tankless gas heater can save a family of four 100–100–200 per year compared to a standard electric tank model.
Many states and utility companies also offer rebates for energy-efficient water heaters. Check with your local energy provider before purchasing.
Step 6: Don’t Forget Installation Requirements
Your renovation timeline depends on a smooth water heater installation. Consider these factors before making your final choice:
Venting (gas models): Gas water heaters need proper ventilation. If your renovation doesn’t include access to an exterior wall or roof, a power-vent or direct-vent model adds cost but offers flexible placement.
Electrical: Tankless electric units often require a dedicated 120-amp or higher circuit. Most homes built before 2000 need an electrical panel upgrade to handle this load.
Water quality: Hard water dramatically shortens water heater lifespan. If you live in an area with hard water — and many parts of the country do — consider installing a whole-house water softener alongside your new water heater to protect your investment.
Step 7: Know When to Hire a Professional
Water heater installation is not a DIY project for most homeowners. Improper installation can lead to gas leaks, electrical hazards, water damage, and voided warranties. Licensed plumbers handle:
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Proper sizing of gas lines and electrical connections
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Correct placement of temperature and pressure relief valves
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Compliance with local building codes and permit requirements
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Safe disposal of your old water heater
If you’re planning a renovation and need a new water heater, EliteHomePlumbers can connect you with licensed professionals in your area who specialize in water heater installations. They vet every plumber for proper licensing and insurance, so you can focus on enjoying your newly renovated home rather than worrying about the installation.
Final Checklist Before You Buy
Before making your final decision, run through this checklist:
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Have I calculated my household’s peak hot water demand?
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Have I compared tank vs. tankless options for my renovation budget?
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Is my fuel type (gas, electric, propane) already available, or do I need to add it?
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Have I checked for rebates and incentives in my area?
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Did I verify the installation requirements (venting, electrical, space)?
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Have I accounted for my local water quality?
Conclusion
Choosing the right water heater during a renovation comes down to balancing your household’s hot water needs with your budget, available space, and energy efficiency goals. For most homeowners, a high-efficiency tank model offers the best value, while those planning long-term or with high hot water demand benefit from the endless supply and energy savings of a tankless system.
The most important step? Working with a qualified professional who can assess your home’s specific setup. For reliable water heater installation in Texas and nationwide, EliteHomePlumbers matches homeowners with pre-screened, licensed plumbing contractors who handle everything from simple replacements to complex renovation installs.
