Dave B plans on installing a range hood in the kitchen of his new house so any evidence of the blackened redfish or pan-seared scallops he might want to cook can be quickly whisked away.
The house will be tightly air sealed, and Dave wonders which of the two Broan kitchen fans he is considering—moving 250 and 390 cubic feet of air per minute respectively—would be best, and whether he should provide a source of makeup air for them.
“I seem to get conflicting information regarding if the unit needs makeup air,” Dave writes in a Q&A post. He wonders whether a clothes dryer also will need some kind of makeup air.
That’s the topic for this Q&A Spotlight.
Even some manufacturers don’t get it
Dave isn’t the only one who’s confused by what he’s heard. Martin Holladay points him toward two articles on this topic that GBA has published in the past (see the “Related Articles” sidebar below). One of them describes the frustrations of a homeowner whose 1,200-cfm range hood was so powerful that it pulled ashes out of the fireplace. She wanted to know what could be done about it.
In poking around for answers, Holladay learned that the manufacturer of the GE Monogram range hood offered no guidance on the topic of makeup air, and in telephone calls to the company, various representatives basically had nothing to offer.
So the problem is not new and not unique.
That said, Tom Wheeler notes that range hoods that exhaust less than 400 cfm do not require makeup air, and Dave’s own research suggests that even in a tight house—one with an air leakage rate of 1.5 ach50 or less—no makeup air should be needed for a vent hood with…
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