What Is Your Home's Bio-Load? A Plain-English Guide for Austin Homeowners

Quick answer: Your home's bio-load is the mix of microscopic particles and microbes that builds up in its air, on its surfaces and inside its HVAC system over time. Humidity at 50% or below, a clean filter and HVAC system, and regular HEPA vacuuming keep it low, and an occasional whole-home dry fog treatment reaches what cleaning misses.

What does "bio-load" mean?

Bio-load is our name for the microscopic mix that collects in a house: dust, pet dander, pollen, cooking residue, skin flakes and the microbes that ride along with them. It lives in the air, on surfaces and inside the HVAC system.

You can't see a bio-load, and a clean-looking home can still carry a heavy one. It isn't a sign that you're a bad housekeeper. It's simply what happens when people, pets and weather share the same air for years.

Think of the film that builds on a windshield: a little every day, kept thin by regular wiping and an occasional deep clean.

How does a bio-load build up over the years?

A bio-load grows slowly. Most homeowners only notice it when the house starts to feel or smell a little "off." Here are the biggest drivers in Central Texas homes.

Humidity

Austin's air is damp for much of the year. When indoor humidity stays above about 50%, dust and fabrics hold more moisture, and microbes settle in more easily. Carpets, closets, bathrooms and the cool spots near AC vents are common trouble areas. Our Central Texas humidity guide covers this in more detail.

Your HVAC system

Your heating and cooling system moves all of the air in your home many times a day. Along the way, particles settle on the filter, the indoor coil, the blower and the inside of the ductwork. The coil stays wet while the AC runs, which makes it a natural collecting spot. Every time the system kicks on, some of that buildup can blow right back into your rooms.

Pets

A dog back from a roll in the St. Augustine grass carries the yard inside, and dogs and cats add dander, hair and saliva on top of that. Pet beds, rugs and couches become small reservoirs of bio-load.

Cooking and daily life

Frying, searing and even boiling water put grease and moisture into the air. Showers, laundry and houseplants add more moisture. All of it settles on cabinets, ceilings and fabrics.

Closed-up homes

Our long cooling season keeps Austin homes sealed up for months. Newer homes are built tight to save energy, which is great for your power bill but lets less fresh air in to dilute what builds up inside. Older homes have their own story: decades of dust in wall cavities, attics and older ductwork.

Seasonal pollen

Cedar in winter and oak and grass pollen in spring all find their way inside on clothes, shoes, pets and open doors.

What are the signs of a high bio-load?

A heavy bio-load mostly shows up as small annoyances that add up:

• Stale or lingering odors that come back soon after you clean
• More dust settling on furniture a day or two after dusting
• A stuffy feel in certain rooms, even when the temperature is right
• A musty or stale smell when the AC first turns on
• Pollen and dander that seem worse indoors than out

In July, when the walk to the mailbox feels like opening an oven, most Austin families spend nearly the whole day inside, so the indoor air sets the comfort level. For questions about how your home's air affects someone in your family, talk with your doctor.

Which habits keep the bio-load low?

Most of these take ten minutes or less and cost little or nothing.

• Change your HVAC filter on schedule. For most homes that's every 1-3 months, and homes with pets or heavy pollen do better at the shorter end. A good pleated filter catches far more than a thin fiberglass one.
• Keep indoor humidity at 50% or below. A simple hygrometer from a hardware store tells you where you stand.
• Run the kitchen and bath fans. Use them during cooking or showering and for 15-20 minutes after.
• Vacuum with a HEPA vacuum. Focus on rugs, pet areas and upholstered furniture.
• Wash bedding and pet beds weekly in warm water.
• Leave shoes at the door. It cuts down on what gets tracked in from outside.
• Keep up with HVAC maintenance. A yearly tune-up that checks the coil and drain line keeps your system cleaner. Gold Eagle Services handles filters, coil cleaning, duct work and whole-home dehumidifiers.

What if habits aren't enough?

Even with great habits, some of the bio-load hides where a vacuum or rag can't reach: inside ductwork, behind furniture, in closets, in cracks and crevices, and up near the ceiling. That's where a whole-home dry fog treatment comes in.

Pure Maintenance's patented VaPURE dry fog system handles those spots in two steps:

1. A fine dry fog of a hydrogen peroxide and peracetic acid solution fills the home. The droplets are so small they float through the air and reach every room, surface and closet, plus the HVAC ductwork, without getting things wet. Afterward the solution breaks down into nothing more than water, oxygen and vinegar.
2. A surface protectant is then applied to help surfaces stay cleaner going forward.

On treated hard, non-porous surfaces, the treatment helps neutralize odors, and it temporarily reduces airborne particulates as the fog settles.

The whole job takes one day. Good times to schedule one: after moving into a new house, after a renovation, at the start of allergy season (cedar season, December through February, for many Austin homes), or when a stale smell keeps coming back no matter how often you clean.

Independent research on dry fog: the U.S. Army Corps of Engineers studied the Pure Maintenance dry fog process. Read the U.S. Army Corps of Engineers case study on Gold Eagle Services' site.

What to do next

1. Check your indoor humidity with a hygrometer and aim for 50% or below.
2. Write today's date on a fresh HVAC filter.
3. If the house still smells stale after a few weeks of good habits, book a free phone consultation.

Get a free phone consultation

Pure Maintenance Austin, brought to you by Gold Eagle Services, serves all of Central Texas, out to College Station (about 2.5 hours), including Round Rock, Georgetown, San Marcos, Bastrop and Marble Falls. Book a free phone consultation: a Comfort Advisor calls you, learns what's going on in your home and sends a written quote based on square footage. Call 512-904-4646 or email IAQ@goldeagleservices.com. We're open Monday through Saturday, 7am to 7pm.