Smoky skies are becoming a seasonal reality in the East Bay. When PM2.5 from wildfire smoke drifts over Danville, Alamo, Walnut Creek, San Ramon, and Pleasanton, your home should be a refuge with clean, filtered air. With a few smart upgrades and settings, you can reduce smoke particles indoors and protect daily routines. This guide shows you what works, how to prep, and what buyers and sellers should know. Let’s dive in.
Why smoke‑ready HVAC matters in the East Bay
Wildfire smoke carries fine particles called PM2.5 that can reach deep into your lungs. Public agencies recommend reducing exposure during smoke events and keeping indoor air as clean as possible. You can learn more about the health context from the California Air Resources Board’s Smoke Ready guidance.
The Bay Area Air Quality Management District issues Spare the Air alerts and has strengthened protections in 2025, which can make alerts more frequent. That means you should expect more days when indoor filtration matters. Stay current on advisories and preparedness steps through the Air District’s wildfire prep resources and local alerts.
The layered approach that works
No single device solves smoke exposure. A layered plan is the most reliable.
Seal and weatherize first
Reducing leaks helps keep smoky air out so your filters work better. Focus on gaps around windows and doors and refresh weatherstripping where needed. The Air District lists weatherization as a practical step on its wildfire safety page.
Upgrade your central filter if the system allows
A MERV 13 filter removes much more PM2.5 than common MERV 8 filters. The EPA explains MERV ratings and why higher MERV captures finer particles in its MERV guide. Before you switch, have a technician check static pressure so your blower can handle the added resistance. Building America guidance outlines design and sizing considerations for high‑MERV filters.
Add portable HEPA air cleaners
A portable HEPA unit provides strong room‑by‑room protection and is recommended for a clean room or for sensitive occupants. Choose a CARB‑certified device and size it by smoke CADR for your room. ENERGY STAR explains how to pick the right CADR in its guide on choosing a room air cleaner, and you can verify devices on CARB’s certified air cleaner list.
Use the right settings during smoke
When outdoor smoke is high, set your HVAC fan to ON so it filters continuously and close any outdoor air intake or set to recirculate. Do not run whole‑house fans or swamp coolers that pull in outside air. CARB’s Smoke Ready page summarizes these steps for preparing your home.
Avoid ozone‑producing devices
Stick with mechanical filtration like MERV and HEPA. California restricts devices that generate ozone, and agencies advise against using ozone for smoke control. Check CARB’s list for certified low‑ozone devices.
Step‑by‑step checklist for Bay Area homes
Pre‑season prep
- Stock the right filters. Know your sizes and keep spare MERV 13 filters or the highest your system supports. The EPA recommends planning ahead in its guide to preparing for smoke and heat.
- Schedule an HVAC check. Ask a licensed pro to measure static pressure, confirm the highest compatible MERV, and review return sizing and duct condition. See design tips for high‑MERV filters.
- Buy a properly sized HEPA unit. Choose a CARB‑certified model and size by smoke CADR. You can review how to size using ENERGY STAR’s air cleaner guide and confirm devices on CARB’s certified list.
- Weatherize. Seal window and door gaps and replace worn weatherstripping. The Air District includes weatherization in its wildfire safety guidance.
- Plan for outages. Consider how you would power fans and HEPA units during heat or Public Safety Power Shutoffs. The EPA covers outage planning in preparing for smoke and heat.
During a smoke event
- Create a clean room. Pick an interior room, close doors and windows, and run a portable HEPA on a higher setting. The EPA provides step‑by‑step clean room guidance.
- Run filtration continuously. Set your central fan to ON if possible and keep the HEPA unit running at the recommended speed for the room size. The EPA notes filters load faster during smoke in its preparation guide.
- Avoid indoor particle sources. Skip vacuuming, candles, fireplaces, grilling, and minimize gas stove use until air improves. See CARB’s Smoke Ready tips.
- If you must go outside, mask up briefly. A properly fitted N95 or similar offers better particle reduction than cloth masks. Alameda Health System outlines local smoky air tips.
After the smoke clears
- Replace dirty filters. Swap HVAC and HEPA filters more often following heavy smoke. Inspect registers and wipe visible residue.
- Check the system. If you see soot on coils or in drain pans, have a professional clean targeted components. The EPA explains when duct cleaning is warranted in its guidance on air ducts in your home.
Options and tradeoffs for East Bay floorplans
- Central HVAC with MERV 13. Great for whole‑home coverage if your air handler and ducts can handle the pressure. Have a pro confirm compatibility first using the high‑MERV design guide.
- Portable HEPA units. Ideal for bedrooms and a designated clean room. ENERGY STAR explains how to choose the right size in its air cleaner guide.
- In‑duct or whole‑house HEPA. Strong protection but usually requires contractor design and higher cost. Many households combine central MERV 13 with one or two HEPA units for a cost‑effective approach.
Costs to expect
- MERV 13 filters. Retail pricing varies by size and thickness. Expect a broad range, and plan for more frequent changes during smoke season. See typical retail examples in Home Depot’s MERV 13 filter listings.
- Portable HEPA air cleaners. Small bedroom units can be under a few hundred dollars, while high‑CADR models for larger rooms cost more. CARB’s certified list helps you verify devices permitted for sale in California.
- HVAC upgrades. From a simple filter change to adding a media cabinet or duct improvements, costs vary. Ask for a static‑pressure assessment and written scope before you commit. Review technical considerations for high‑MERV designs.
For buyers and sellers in the East Bay
Smoke‑season readiness is becoming a practical feature of home habitability. If you are selling, document factual items such as filter sizes, the date of your last HVAC service, whether the system can accept MERV 13, any return or duct improvements, and the presence of portable HEPA units. If you are buying, ask about these same details and look for a simple clean‑room setup plan and sealed windows and doors.
Ready to position your home with confidence or find a property already set up for cleaner air days? Connect with Cynthia Money for guidance tailored to East Bay living and introductions to trusted local pros.
FAQs
What is the best HVAC filter for wildfire smoke in the Bay Area?
- Public‑health and building guidance recommend using MERV 13 or the highest MERV your system supports to capture more PM2.5, as outlined in the EPA’s overview of MERV ratings.
Should I run my HVAC fan continuously during smoke events?
- Yes, set the fan to ON so air recirculates through the filter and close any outdoor air intake or set to recirculate, consistent with CARB’s Smoke Ready recommendations.
Do I still need a portable HEPA cleaner if I upgrade my furnace filter?
- Often yes, because a properly sized HEPA unit in a clean room gives reliable room‑level protection, while central filtration improves whole‑home air; using both together is a strong strategy backed by the EPA’s preparation guidance.
How do I set up a clean room at home?
- Choose an interior room, close windows and doors, seal gaps, and run a portable HEPA on a higher setting; follow the EPA’s step‑by‑step clean room guide.
Are ozone or ionizer air cleaners recommended for smoke?
- No, agencies advise avoiding ozone‑generating devices in occupied homes; rely on mechanical filtration and verify devices on CARB’s certified air cleaner list.
