BoilerBuying Guide2026-03-10
What Size Boiler for a 3-Bedroom House?
Sizing depends on heat loss and bathrooms, not just bedrooms — a calculation is essential.
Bedroom count is a rough guide at best; proper sizing uses heat loss and hot-water demand.
Why bedrooms aren't enough
Two homes with three bedrooms can have very different heat loss depending on insulation, age, windows and layout.
How we size it
We calculate your home's heat loss and peak hot-water demand to recommend the right output and flow rate.
Key takeaways
- Bedrooms are only a rough guide
- Heat loss and bathrooms matter
- We do a proper calculation
- Avoids over- and under-sizing
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Licensed, gas-certified technicians serving Greater Vancouver since 1999. CombiBoiler.ca — A division of ROMA Heating Ltd..
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