Quiet, Continuous, Balanced Air
In small, highly insulated attics, steady low-flow ventilation beats on/off bursts. Pair a variable-speed heat pump (for temperature and dehumidification) with a small ERV set to continuous trickle (e.g., 30–60 CFM). Balance supply and exhaust to avoid pressure imbalances that pull air from cracks.
Smarter Exhaust, Better Ducts
Use a low-sone bath fan on a humidity timer for peak events and duct outdoors with insulated, smooth pipe and a backdraft damper. Keep runs short, avoid soffit terminations, and seal connections with mastic—not tape—so noise and moisture don’t creep back in.
Filtration & Monitoring
Specify MERV-11+ filtration on the HVAC zone, change filters seasonally, and add a CO₂/RH monitor. Target 40–50% RH and CO₂ under ~1000 ppm during sleep for crisp mornings without dry air.
Details That Prevent Drafts
Place supply diffusers away from the bed and use broad-throw registers instead of pencil jets. Undercut doors or add transfer grilles if you use separate rooms so pressure equalizes quietly.
Explore attic-friendly ERV layouts and diffuser placements in our NYC attic ventilation & air quality guide.