Upgrade HVAC filters to MERV 11-13

What to Do

Replace standard fiberglass HVAC filters with MERV 11-13 pleated filters. Replace every 60-90 days during pollen season. Run the fan continuously ("fan on" not "auto") on high-pollen days.

Why It Works

Standard HVAC filters (MERV 1-4) catch less than 20% of pollen-sized particles. MERV 13 captures 85-95% — the level recommended by ASHRAE for improved indoor air quality. Running the fan continuously filters air even when heating/cooling is not active.

Tips

• Do not exceed MERV 13 without confirming your HVAC system can handle the air resistance
• 4-inch-deep filter housings allow higher MERV ratings with lower restriction
• Replace more frequently during pollen season than the manufacturer default
• This filters air throughout the entire home, unlike a portable purifier which covers one room