Ask Woodiwiss: how should I ventilate a room while painting?

The obvious way to ventilate a room while painting is by opening the doors and windows for natural ventilation. As we’ve discussed before about paint fume dissipation, you could cycle fresh air and any paint fumes or smells multiple times an hour with the windows open. Coupled with today’s modern paint formulas, that chemical smell of fresh paint will likely be unnoticeable in about 36-48 hours.

With some exceptions with oil-based paints, most paint today is low in volatile organic compounds, or low-VOC, and generally not harmful to people or pets. But even no-VOC paints have some odor to them. 

If you’re worried about the kids, pregnant women, or someone suffering from breathing or asthma problems — or just find the paint fumes onerous and headache-inducing — you can speed up the ventilation process with these additional steps. 

Use box fans to circulate fresh air

Box fans placed near windows or doors can help flush in more air. Ventilate a room while painting by placing the fans strategically throughout the house. 

• Always place a fan by the door, with the air flowing in. It might seem counterintuitive, but you want to cycle fresh air outside into the house, not blow the fresh paint smell out of the house. A newly painted room needs to dry, and blowing fresh air into the house from your largest openings helps circulate air.
• Position a few box fans throughout the house to create a draft cycle so air comes in from a front door, then up the stairs, down a hall, and into a freshly painted room.
• A window can provide enough ventilation if you’re only painting a small space or room. Just remember to open another window across the house or nearby to get cross-house airflow.
• You could also opt to shut the doors leading to the smaller space. This will require a slightly longer drying period, maybe up to half a day more. But strong paint fumes will be limited to the smaller area — if you can spare it for a while.

Carpet blowers, standalone fans, special-fitting box window fans, and other exhaust fans can work, too.

Position air purifiers with activated charcoal

The best air purifiers use a HEPA-grade filter with an activated charcoal “pre-filter,” usually a thinner black mesh that pulls air from the room through the filter and out again. Depending on the size of your space and purifier, these may take a while to work. 

The activated charcoal helps eliminate unpleasant odors, but remember that despite their name, air purifiers do not remove toxic fumes. So if you’re reading this and assuming they’ll work when using more toxic chemicals, like varnish, they are not replacements for proper ventilation and masks.

Use the kitchen range hood and bathroom exhaust, if it ventilates outdoors

If you’re painting the kitchen, turn on the overhead range hood — if it blows exhaust outdoors. 

Many range hoods simply pull air up from the range and up and out overhead (a common source for yellowing and grease stains on kitchen ceilings). They’re usually not large fans, either, but in a kitchen it can help encourage constant airflow.

In the bathroom, ceiling exhaust fans can help pull air up and out of the home. However, in the bathroom exhaust fans don’t vent outside in older homes. Instead, they merely blow air up into the attic. That might be sufficient ventilation to get the smelly air out of the bathroom, but recognize it’s just moved from one room to another — and might even spread it across the entire house.

Turn on your central ventilation system

Even if the temperature is pleasant outside, turn on the whole-house ventilation system if you have one. You can opt to close air vents in select rooms, but a mechanical ventilation system is designed to fully refresh your home’s air every two or three hours. Combined with one or more fans, you’ll be able to carry unpleasant odors away and keep air moving as paint cures.

You do not have to run the furnace or air conditioner if it’s a comfortable day. Instead, just turn on the blower fan. You’ll use far less energy, won’t waste electricity or gas, and treat it for what it is: a giant whole-house fan.

As a bonus, many hardware stores carry activated charcoal pre-filters for HVAC systems. Placing one right before your existing air filter can significantly improve indoor air quality and eliminate paint fumes at a scale most standalone air purifiers can’t match. You might even consider replacing them each season, like your existing filter, so you enjoy a steady flow or odor-free air all year. 

Most importantly: give it time. Freshly painted rooms have a significant amount of water on the walls that has to dry. Like curing a piece of pottery, the best method is to be patient and give it time.

Avoid these myths — they don’t reduce paint fumes quickly or noticeably 

We’ve been in a few homes where people have tried to make up for a poorly ventilated space in unusual ways. We see these techniques to try and reduce unwanted smells, but they don’t work. Or if they do, not in a way anyone can notice.

• Place buckets filled with water around the room, presumably believing the water will “absorb” the VOC fumes. They don’t. If anything, they might slow the process of drying the walls by adding humidity back into the room on a warm day.
• “Freezing air” by blasting the air conditioner. The temperature of the air does nothing to odors or harmful fumes of any kind. This is really pushing the air conditioner to cycle air — which does help — and masking the odors by changing the air temperature. Warm air rises, so cold air falls to the floor — further away from our noses. Chilling the air to unusually low temperatures does nothing but make everyone uncomfortable, wastes energy, and might even put pets and small children (who are closer to the ground) at higher risk.
• Setting bowls of vinegar or apple cider vinegar around the room while painting doesn’t work any better than spraying Febreze or other air fresheners. The theory goes that the acidity of the vinegar latches on to odors and neutralizes them. That can work, but a few bowls or even buckets in a typical room isn’t going to cut it. This technique does not ventilate the room and works by merely covering up the paint fumes so we go “nose-blind” to the original problem. They do nothing to eliminate odor.
• Other harmful chemicals in cleaning agents may do just as much to stuff up a room with subpar air as the paint fumes you’re trying to reduce.

Ready to get started on your next painting project? 

Our teams come to each job with powerful exhaust fans, box fans, and more that reduce odor and fumes quickly. 

If you’re concerned someone in your home may have other chemical sensitivities, let us know, and our professional paint consultants can identify a high-quality low-VOC paint designed for minimal paint fumes that will work best in your home and won’t sacrifice coverage or quality.

Call (925) 595-3081, email info@woodiwisspainting.com, or message us online.