The answer is it depends on the leakiness of the building. The maximum flow through a Model 3 fan at 50 Pa is about 5,800 CFM. A 10,000 square foot house that was built with airtightness in mind may not have 5,800 cfm of leak while a 1,200 square foot Georgian with huge holes to various parts of the building may not be able to reach 50 Pa with the Model 3 fan at full speed. With this information, that is why our fans are rated based on the amount of flow each can generate.
What is the maximum square footage that can be tested with a single fan Model 3 blower door?
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