Everything you need to improve your indoor air quality, organized by time commitment. Start with 60 minutes and build from there.
Do this today. No purchases required.
Minutes 0–15: Establish your baseline (free) Open a window for 5 minutes, then close it. Use a free monitor (or the PurpleAir app) to note outdoor PM2.5. Then check indoor levels 20 minutes later with windows closed. The gap tells you how much protection your home already provides.
Minutes 15–30: The incense leak test (costs ~$2) On a windy day, light an incense stick and walk slowly around every door, window, outlet, and floor-wall joint. Where smoke moves, air moves. Mark each leak with a sticky note. This becomes your sealing shopping list.
Minutes 30–45: Relocate your purifier to the bedroom If you already have an air purifier, move it to your bedroom. Position it at least 18 inches from walls, not aimed directly at the bed. Run it on medium overnight. Your bedroom is where you spend the most consecutive hours.
Minutes 45–60: Build your shopping list Based on your leak audit, write down the weatherstripping and caulk you need. Use our CADR calculator to determine what purifier size your rooms need (length × width × height ÷ 12.5 = minimum CADR). You now have a plan, not just a worry.
Budget: $50–$200. Time: 2–4 hours spread over a week.
Day 1–2: Seal your bedroom door Install a door sweep ($15–25) and foam weatherstrip on the frame ($8–15). These two steps dramatically reduce air exchange between your bedroom and the rest of the house.
Day 2–3: Outlet gaskets throughout Install foam outlet gaskets on all outlets and switches on exterior walls ($5–8 per pack of 12). Turn off power at the breaker, remove cover plate, install gasket, replace plate. This takes 2 minutes per outlet and has surprisingly significant cumulative impact.
Day 3–4: Caulk bedroom windows Apply paintable silicone caulk around bedroom window frames where they meet the wall. Or use rope caulk (removable, renter-friendly) around window sashes. Focus on the side of your home facing the landfill/prevailing wind first.
Day 4–5: Add an air quality monitor Purchase a monitor with PM2.5 and TVOC reading — the Temtop M10 (~$65) is the best entry-level choice, or the Awair Element (~$150) if you want Wi-Fi and CO₂. Place it at breathing height, at least 6 feet from your purifier.
Day 5–7: Right-size your air purifier If you don't have one or it's undersized, the Levoit Core 300 handles bedrooms up to 220 sq ft, and the Coway AP-1512HH covers up to 360 sq ft. Both have true HEPA and activated carbon. Run continuously on low or auto mode.
Budget: $200–$700 total. Whole-home approach.
Week 1: Complete bedroom optimization Finish the bedroom air quality system: sealed door, weatherstripped windows, properly-sized HEPA + carbon purifier, and a monitor. This is your "clean room"—a reliable refuge regardless of what's happening outside.
Week 2: Seal the whole house Work systematically through every exterior door (door sweeps + weatherstripping), all windows (silicone caulk), outlet gaskets on all exterior walls, and plumbing penetrations (spray foam). See our complete sealing guide.
Week 3: Expand filtration to main living areas Add a second purifier sized for your main living space — the Winix 5510 is our top pick for living rooms up to 360 sq ft. Upgrade your HVAC filter to MERV-13. Review monitor data — are your improvements showing in lower indoor PM2.5?
Week 4: Balance ventilation Check whether your sealed home maintains comfortable CO₂ levels under 1,000 ppm — the Airthings View Plus tracks CO₂ alongside radon, PM2.5, and VOCs simultaneously. If levels creep up, implement a strategic window-opening routine during good outdoor air quality periods. Set filter replacement calendar reminders.
Use this as a reference to ensure you've covered all the bases. Check things off as you complete them.
Each guide builds on the previous one. Start from the beginning or jump to what's most relevant to your situation.