How to know if I need an 80k or 100k BTU furnace
Contractors often give conflicting estimates and recommendations, leaving homeowners unsure whether to downsize or stick with their current capacity. This confusion makes it difficult to choose the correct size without risking a home that is either underheated or overpaying for equipment.
What people tried
Every workaround mentioned in the threads below. We haven’t tested any of them — and nobody here is claiming they worked.
- 1Getting multiple contractor estimates
- 2Collecting and comparing replacement quotes from multiple contractors
- 3Consulting online forums for advice on proper sizing
In their words
Unedited, grouped by where they were said, most upvoted first within each place, each linked to the thread it came from.
“How can i determine if the 60,000 or 80,000 btu is best?”source ↗
“I am getting very different quote and very different information.”source ↗
“Trying to decide whether 80k is enough vs replacing with another 100k (including humidifiers.)”source ↗
“Also very confused about the disparity between contractors with the BTU offering. From 80k and 100k.”source ↗
“Main question: Would you go with an 80k 2-stage/variable-speed furnace, or is there any reason to stay at 100k?”source ↗
Where this came up
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