Indoor Air Quality & HEPA Filtration

MERV 8 is the standard residential filter — captures larger particulates (dust, lint, pet hair) but lets fine particulates through. MERV 11 captures smaller particles including most airborne allergens. MERV 13 captures fine particulates including bacteria and PM2.5 — often considered the sweet spot for households with allergies. MERV 16+ is HEPA-equivalent — captures viruses and ultrafine particulates, but requires furnace airflow capacity to handle the increased pressure drop. We confirm furnace can handle higher MERV ratings before recommending.

For airborne pathogens passing through the air handler — yes, UV-C light is effective at deactivating bacteria and viruses with sufficient exposure time. For surface mold and biofilm in the ductwork — yes, UV light installed near the cooling coil prevents mold growth on the coil itself. For comprehensive protection against household pathogens — UV is one tool among several, not a complete solution. The systems are reasonably priced and meaningfully effective for what they target.

For allergies caused by airborne particulates (pollen, pet dander, dust mites) — meaningfully yes. HEPA filtration in particular can reduce indoor airborne allergen concentration by 80–95%. For allergies to substances that aren't airborne (food allergies, contact allergies) — IAQ systems won't help. For allergies that are partly seasonal and partly chronic, IAQ systems significantly improve indoor environments during peak seasonal periods.

Highly dependent on the specific household's needs. For a healthy household with no allergies or respiratory issues, IAQ system upgrades produce modest, hard-to-measure benefit. For households with severe allergies, asthma, or immune-compromised members, comprehensive IAQ systems can produce dramatic quality-of-life improvement. We recommend based on actual household need, not the most expensive equipment available.

Portable HEPA air purifiers (Coway, Levoit, Dyson) work well for the room they're in, but only that room. Whole-home systems integrated with your furnace clean every cubic foot of air that passes through your HVAC, which means every room. For households where one or two rooms need particularly clean air (a bedroom for someone with severe allergies), a portable unit may be cheaper and adequate. For whole-home cleanliness, integrated systems are more effective.

Standard MERV 8 filters: every 1–3 months. High-MERV (11–13) filters: every 3–6 months. HEPA cabinet filters: annually. Electronic air cleaner cells: annual cleaning, no replacement. UV bulbs: annually. Carbon filters: every 6–12 months depending on usage. We can include these in maintenance plan visits.