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. Check indoor levels 20 minutes later with windows closed. The gap tells you how much protection your home already provides. EPA considers indoor PM2.5 above 12 µg/m³ as elevated.[2]
Minutes 15–30: The incense leak test (~$2) On a windy day, light an incense stick and move it slowly along every door frame, window edge, outlet, and floor-wall joint. Where smoke deflects, air is moving through. Mark each gap with a sticky note — this becomes your sealing shopping list. Research shows the average home loses about 30% of its conditioned air through unintentional infiltration.[3]
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. You spend roughly 8 hours per day in the bedroom — more uninterrupted time than any other room — making it the highest-value location for filtration.[4]
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 size your rooms (length × width × height ÷ 12.5 = minimum CADR). You now have a plan, not just a worry.
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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 — creating a "clean room" effect you can sleep in.
Day 2–3: Outlet gaskets on exterior walls Install foam outlet gaskets on every outlet and switch on an exterior wall ($5–8 per pack of 12). Turn off power at the breaker, pull the cover plate, install, replace. Two minutes per outlet. The DOE estimates air leakage through outlets and switches can account for 1–2% of total home infiltration — small per outlet, significant across a whole house.[3]
Day 3–4: Caulk bedroom windows Apply paintable silicone caulk around window frames where they meet the wall. Use removable rope caulk around window sashes if renting. Focus on the side of your home facing the landfill or prevailing wind first.
Day 4–5: Add an air quality monitor Get a monitor that reads PM2.5 and TVOCs. The Temtop M10 (~$65) is the best entry-level option. The Awair Element (~$150) adds Wi-Fi and CO₂ tracking. Place it at breathing height, at least 6 feet from your purifier. EPA's 24-hour PM2.5 standard is 35 µg/m³ — you want to be consistently below 12.[2]
Day 5–7: Right-size your air purifier The Levoit Core 300 handles bedrooms up to 220 sq ft. The Coway AP-1512HH covers 360 sq ft. Both have true HEPA (captures 99.97% of particles ≥0.3 µm[5]) and activated carbon. Run on low or auto continuously — not just when you notice an odor.
Budget: $200–$700 total. Whole-home approach.
Week 1: Complete bedroom optimization 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. Studies of children in urban environments show even short-term bedroom air quality improvements measurably reduce overnight respiratory symptoms.[6]
Week 2: Seal the whole house Work 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 for your living space — the Winix 5510 is our top pick for 360 sq ft. Upgrade your HVAC filter to MERV-13 — a study of wildfire smoke found MERV-13 filters reduced indoor PM2.5 by up to 80% compared to standard filters.[7] Check your furnace manual for compatibility first.
Week 4: Balance ventilation Check whether your now-sealed home maintains CO₂ below 1,000 ppm — the Airthings View Plus tracks CO₂ alongside radon, PM2.5, and VOCs simultaneously. If CO₂ creeps up, add targeted ventilation during good outdoor air quality windows. Set filter replacement reminders — a clogged HEPA loses up to 50% of its rated efficiency.[8]
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.