Making Indoor Air Actually Breathable in the Northwest

Indoor air quality in Northwest homes has gotten complicated with all the conflicting advice flying around. As someone who’s dealt with every moisture problem and ventilation challenge this region throws at you, I learned everything there is to know about what actually makes a difference. Today, I’ll share it all with you.

Our wet climate and cold winters create a perfect storm for air quality issues. Understanding what you’re dealing with is half the battle.

What Makes Northwest Indoor Air Different

The constant dampness outside leads to problems inside. Mold loves our climate. High humidity warps wood and makes everything feel clammy. And when we seal homes tight against cold winters, we trap all kinds of pollutants inside with us.

Mold and Mildew

Probably should have led with this section, honestly — it’s the signature Northwest problem. Anywhere moisture accumulates, mold follows. Basements, bathrooms, kitchens, even closets against exterior walls. Those spores trigger respiratory issues and allergic reactions in lots of people.

Humidity Levels

Above 60% relative humidity and you’re growing mold and feeding dust mites whether you see it or not. Below 30% and you get dry skin, irritated airways, and static electricity everywhere. The sweet spot is 30-50%, which takes active management in this climate.

Ventilation Traps

Energy efficiency means tight house envelopes, which is great for heating bills and terrible for air quality. VOCs from furniture and cleaning products, carbon dioxide from breathing, smoke from cooking — it all concentrates indoors when fresh air can’t get in.

What Actually Helps

This needs a multi-pronged approach. No single fix handles everything.

Control the Moisture

• Dehumidifiers in problem areas, targeting 30-50% relative humidity
• Exhaust fans in bathrooms and kitchens — use them every time
• Fix leaks immediately, not when it’s convenient
• Run exhaust when cooking, showering, or doing laundry
• Mold-resistant materials for any repairs or renovations

Get Fresh Air Moving

• Open windows when outdoor air quality is good
• HRVs (Heat Recovery Ventilators) provide fresh air without losing all your heat
• Change HVAC filters regularly — dirty filters just recirculate dirty air
• Keep interior doors open for better circulation between rooms

Stop Pollutants at the Source

• Low-VOC or no-VOC paints and cleaning products
• No smoking indoors (obvious but often ignored)
• Carbon monoxide detectors near any combustion appliances
• Proper venting for gas stoves, fireplaces, and space heaters

Clean Regularly and Properly

• Damp dusting traps particles instead of launching them airborne
• HEPA vacuum, not regular — huge difference in what stays captured
• Wash bedding, curtains, and soft furnishings to remove accumulated allergens
• Clean air ducts periodically to prevent dust buildup

Air Purifiers

• HEPA filters for particle removal in high-use rooms
• Place purifiers where you spend the most time
• Follow manufacturer filter replacement schedules — dirty filters don’t filter

Natural Approaches

That’s what makes air quality improvement endearing to us DIY types — some solutions cost almost nothing.

Houseplants

Spider plants, snake plants, and peace lilies filter certain pollutants from air. Don’t expect miracles — they’re supplements, not primary filtration. But they help and they look nice.

Natural Cleaners

Baking soda, vinegar, and lemon clean effectively without adding chemical loads to indoor air. Simple switches that add up over time.

Monitoring What’s Happening

You can’t fix what you can’t see. Regular monitoring catches problems before they become serious.

Consumer Monitors

• Indoor air quality monitors track humidity, temperature, PM2.5, and other key metrics
• Check readings regularly and act on what they show

Professional Help

• If you notice persistent mold, unexplained health symptoms, or musty odors, get a professional assessment
• Pros can find hidden problems and suggest targeted solutions

Northwest indoor air quality requires ongoing attention, not one-time fixes. Start with moisture control and work outward from there. Every improvement compounds over time.