Know Your HVAC
Air Quality Guide

Air Quality Upgrades Explained

Every IAQ product you'll see on an HVAC quote — what actually works, what the independent research shows, and which ones are pure margin for the contractor.

The two-question filter: Does independent, peer-reviewed evidence show this works in real residential conditions? And does your home actually have the problem it solves? Most IAQ pitches fail one or both. See the full breakdown article for the complete tier analysis.

Tier 1 — Actually Works

Tier 2 — Sometimes Works, Often Oversold

Tier 3 — Mostly Marketing