Severe heat, wildfire smoke, and power outages can affect indoor comfort and air quality. Conditions vary by building, equipment, and local guidance. Use this planning guide to collect the information needed to compare options; it does not provide a load calculation or guarantee safe indoor conditions.
For related equipment selection context, see our portable heat-pump and dual-hose AC sizing guide and HEPA air purifier CADR guide.
Thermodynamic Heat Load & Envelope Sizing
Room area alone cannot establish the cooling capacity a home needs. The U.S. Department of Energy’s Building Science Education Solution Center explains that HVAC sizing should account for heating and cooling loads; square-foot rules of thumb can result in oversized equipment. For a home or a complex room, use a qualified professional and an appropriate load calculation rather than applying a universal BTU-per-square-foot figure.
Record the room’s floor area, ceiling height, window exposure, shading, insulation, air leakage, and heat sources. These details help frame a conversation with a qualified HVAC professional, but they do not replace a load calculation.
Air Filtration CADR & Particulate Physics
For wildfire smoke, EPA recommends a portable air cleaner with a smoke CADR of at least two-thirds of the room’s floor area (in square feet). EPA’s example table gives 195 CFM for a 300-square-foot room with an 8-foot ceiling; for higher ceilings, EPA advises choosing a higher CADR. Treat this as a selection aid, not a guarantee of a particular particle level. Check the product’s smoke CADR and room guidance, and follow its operating and maintenance instructions.
For central forced-air systems, EPA advises using a MERV 13 filter or the highest-efficiency filter the system can accommodate. Check the HVAC manufacturer’s instructions or ask a qualified technician before changing filter type. Filtration is one part of indoor smoke management; follow current local guidance and reduce indoor particle sources where practical.
Climate Resilience Equipment Decision Matrix
| Option | What to check | Important limitation |
|---|---|---|
| Portable air conditioner | Room-specific capacity guidance, electrical requirements, and exhaust setup in the exact model manual | Room heat gain and building conditions affect performance; a square-foot estimate alone is not a load calculation. |
| Portable air cleaner | Smoke CADR and room size on the product label; operating noise and filter availability | CADR addresses particles; filtration does not remove every pollutant or guarantee a concentration. |
| Central HVAC filter | Highest filter efficiency permitted by the HVAC manufacturer; fit and replacement instructions | A higher-efficiency filter may not be suitable for every system; consult the manufacturer or a technician. |
| Backup power | Continuous and starting requirements from each device’s manual/nameplate, and the power source’s ratings | Loads and starting needs vary by exact model; installation and transfer equipment may require a qualified electrician. |
Emergency Power Architecture & Load Management
Portable generators and power stations have model-specific continuous and surge ratings. Do not size a source from generic appliance wattages or a single household threshold.
Power Allocation Budget
Make a device-specific list before selecting backup power:
| Device | Running watts from label/manual | Starting or surge watts, if specified | Source rating and margin checked? |
|---|---|---|---|
| Cooling equipment | [write here] | [write here] | [write here] |
| Air cleaner | [write here] | [write here] | [write here] |
| Lights / communications | [write here] | [write here] | [write here] |
Compare the total simultaneous load and starting demand with the exact power-source manual. Follow manufacturer instructions and applicable local rules. Have a qualified electrician assess any fixed wiring or transfer switch. Operate fuel-burning generators outdoors, at least 20 feet from windows, doors, and vents, and use a battery-powered or battery-backup CO detector in the home, as CDC advises. Follow the generator manual for its specific setup and operation.
Sanctuary Room Sizing Record
Use this record to organize questions and verified product details rather than to certify a room as safe:
- Room dimensions, ceiling height, window exposure, and expected occupancy: [write here]
- Local heat, smoke, or evacuation instructions and where to check updates: [write here]
- Cooling product model and its room-sizing, electrical, and exhaust instructions: [write here]
- Air-cleaner model, smoke CADR, stated room size, and filter replacement guidance: [write here]
- HVAC filter type permitted by the equipment manufacturer or confirmed by a technician: [write here]
- Device running/starting loads and compatible backup source, if used: [write here]
Keep doors and windows closed during smoke when public-health guidance says it is appropriate, while following local safety instructions and equipment manuals. Do not block HVAC registers, seal combustion-air openings, modify ducts, or connect equipment in ways the manufacturer does not allow. No room setup or consumer air cleaner guarantees protection from smoke or heat; follow emergency alerts and seek a safer location if authorities advise it.
