May is Asthma Awareness Month, and CMM's coverage this week loops back to a problem we already write a lot about: pollen, mold, and the role of exterior glass in carrying allergens indoors. Here's the through-line, and the tools we built around it.
May is Asthma Awareness Month, and Cleaning & Maintenance Management ran a piece on Monday about the cleaning industry's role in allergen management for the millions of Americans living with asthma. Worth reading. The piece focuses on interior surfaces — carpet, HVAC, soft furnishings — and on the products and protocols that reduce indoor allergen load.
We want to extend that conversation by half a step. Windows are an allergen reservoir, and the part of the cleaning trade that handles them sits inside the indoor-air-quality story even when nobody invites us to.
Three places, mostly.
Pollen accumulation on horizontal sash bottoms. Springtime tree-pollen waves deposit on horizontal surfaces, and the bottom sash of a double-hung window, the muntin tops on a divided lite, and the threshold of a sliding glass door are all horizontal traps. When the window opens, that pollen mobilizes. For a sensitive household, the difference between an unwashed and a properly washed bottom sash at the start of pollen season is real and noticeable. We've written about the seasonal pollen problem on residential windows and the practical timing for May washes.
Mold and mildew at the IGU perimeter on north-facing units. Cold-side condensation creates a thin moisture film on the interior glass and on the frame perimeter. North-facing units in humid climates run the highest mold-load reservoir, and our IGU Self-Check walks through what's surface mold (cleanable) versus what's an interpane seal failure (a different problem entirely).
Bioaerosols carried in by reopening a window after rain. Less well-documented, more anecdotal. When a window has been closed against rain and is reopened, the exterior glass film — wet, dried, wet again — can carry a heavier microbial load than a continuously-clean window. Pure-water-fed-pole systems are particularly good at this part of the cleaning because they leave no surfactant residue for the next biofilm to adhere to.
Two tools on the site speak directly to this:
The Pure-Water TDS Diagnostic is the right starting point for any cleaner who wants to position pure-water residential service as an allergen-management offer. Pure-water cleaning leaves zero mineral residue, which means no surfactant film for pollen to bond to. It's a real differentiator on a residential route if you can communicate why.
The Cleaning Schedule Builder bakes pollen-wave timing into its regional recommendations. For an asthma-sensitive household, the right cadence is usually two to three exterior cleans through April–June rather than the standard spring–fall pair.
If you do residential commercial in a pollen-heavy market — Atlanta, Nashville, Memphis, the Carolina Piedmont — Asthma Awareness Month is a low-effort, high-relevance touch point for talking about service frequency with sensitive customers. The trade press tends to write the indoor-cleaning angle. The exterior side is yours to write.
Filed by the Window Washing Guide News Desk.