Every spring my phone lights up with people who want sparkling windows for Mother's Day. Every spring I tell most of them to wait. Here's why — and what to do if you can't.
Last Saturday morning I was finishing a house in Birmingham, Michigan. The owner, a very nice woman who had been very patient about scheduling, came out with coffee and stood next to the back patio looking at the kitchen window I had just done. The light was good. The window was clean. She tilted her head and said, "It already has stuff on it."
She wasn't wrong. The window had been clean for about forty minutes. In that time, the wind had shifted, a maple tree thirty feet away had decided it was time, and a fine yellow-green dust had settled on the outside of the glass. Not enough to ruin the wash. Enough to be visible if you looked for it.
This is the May problem. Every spring my phone lights up — Mother's Day is coming, the realtor wants the listing photos shot, the in-laws are visiting — and people want sparkling windows. Every spring I tell most of them to wait until June. Here's why, and here's what to do if waiting isn't an option.
Pollen. This is the obvious one. Maples, oaks, birches, and grasses are all dumping it through May, and the timing varies by week and by neighborhood depending on which trees you're under. The pollen itself isn't a hard cleaning problem — it's water-soluble, and a microfiber cloth with plain water handles it. The problem is that it never stops arriving. You wash a window Friday afternoon. By Sunday morning, when the family pulls in, the bottom third of the glass has a faint chartreuse haze on it again.
Pollen plus rain plus pollen. This is worse. The pollen lands, it rains lightly, the pollen sticks, then more pollen lands on the rain residue, and you end up with a layered film that needs an actual wash, not a wipe. If you've had a sequence of dry-rain-dry-rain in the last week, the windows you cleaned a month ago might already look worse than they did before you cleaned them. (Mara wrote a whole piece on why this happens — the short version is that cleaning makes a fresh dirt-tracking surface, and the next round of dirt shows up sharper against it.)
Construction season. The trades come back in May. Roofers, masons, painters, landscapers grinding stumps. If your neighbors are renovating, or if you are, the dust is in the air and on your windows for weeks at a time. A house I do every spring sits two doors down from a perpetual remodel and there is nothing I can do about that house's windows in May. We've moved them to early July, after the masonry guys finish.
The combined effect is that windows washed in May get visibly dirty fast — sometimes within hours — and homeowners interpret that as a bad clean. They'll call back. They'll leave a review. And it isn't a bad clean. It's just that the air is full of stuff and the stuff lands on the cleanest available surface, which is the window I just did.
If I could give one piece of timing advice to homeowners, it would be this: the best six-week window for cleaning residential glass in the upper Midwest is mid-June through late July. The pollen has mostly settled. The masonry dust has settled. The summer storm pattern is still mostly forming, not landing. Your windows will look good for a month, sometimes longer, instead of looking good for a weekend.
The second-best window is mid-September through October. Cool, dry, the trees haven't dropped their tannin-heavy leaves yet, and the sap from the spring growth has hardened and is now mostly being shed in the form of the seasonal solvent-ladder candidates I deal with every fall.
May is the worst month. November is the second-worst, but for different reasons (cold-weather streaks, water that won't dry, salt creeping into glass cleaner solutions). December through February is fine for storefronts but largely impossible for residential because the water freezes on the glass before you can squeegee it.
So: the simple version is, if you can wait until mid-June, wait. Your money goes further.
But you can't always wait. The Mother's Day brunch is Sunday. The realtor wants the listing photographed Tuesday. Here are the three things that actually help.
Inside glass is shielded from pollen, rain, construction dust, and bird strikes. It collects fingerprints, kitchen grease, dog-nose smudges, and the occasional misplaced highlighter. It's a much cleaner cleaning job, in both senses, and the inside surface is what people actually notice when they're sitting in your living room.
The outside glass is what people notice when they pull up the driveway, but they notice it for two seconds. The inside they look at for two hours. Allocate accordingly. If you only have time and money for one side this month, do the inside, and do it well — a proper four-stage wash on the interior gets you 80% of the visual benefit for half the work.
If you must do the outside, watch the forecast and pick a day that has just rained. Not a day before rain — a day after. A real soaking rain, not a five-minute shower, will pre-rinse your windows. The pollen comes off. The dust comes off. The film comes off. You're now cleaning a window that's already partway clean, which means your wash water stays cleaner, your scrim and microfiber cloths last longer, and the result is significantly better.
The timing window is roughly the morning after a substantial overnight rain. If you wait three days, the pollen comes back and you're fighting it again. If you do it during the rain, the wind drives spray onto the glass and you fight your own runoff.
This is the trick the pros use in May. We watch the radar. We work the routes that match the weather. A house I do annually in Royal Oak has been on the post-rain Tuesday rotation for four years.
This is the one no one wants to hear. In May, your windows are not going to stay perfect, and trying to make them perfect is going to make you crazy. Do a fast pass instead of a deep wash. Skip the screens. Skip the frames. Use a pole-fed water-fed-pole setup if you have one — it leaves a slightly different finish than squeegee work, but it's twice as fast and the results are good enough for the second-tier windows. Save the deep work for June.
When I'm doing my own house in May, I do a fifteen-minute pass instead of a sixty-minute pass. I know it'll need redoing. I'm fine with that. The point is to get the worst of the haze off, not to achieve a perfect surface that the air is going to ruin in a week anyway.
You will see, in May, advertising for "long-lasting" or "rain-shedding" glass treatments — Rain-X for windows, hydrophobic sealers, ceramic coatings repurposed from the auto-detail industry. The pitch is that you treat your glass once and the rain pushes the pollen off for you. It is appealing. It is also bad advice for residential windows, and Easton has a piece coming on exactly that. Don't buy the spray.
If you want a real shortcut for May, the only honest one is distilled water for the rinse step. It's three dollars a gallon at any grocery store, it dries with no minerals, and on a pollen day it's the difference between a window that streaks at noon and one that doesn't. Dawn solution, distilled water rinse, microfiber finish. That's the play.
Wait for June if you can. If you can't, do the inside, time the outside to the weather, and accept that your standards have to drop for a few weeks. That's not a failure. That's the season.
Mother's Day is tomorrow. Your windows are not going to be perfect. Your mother is going to be fine.
Jan Davenport is a staff writer at Window Washing Guide. He runs an eleven-year residential route in suburban Detroit and writes mostly about practical fieldwork and pricing. He has cleaned the windows in this piece's anecdote forty-seven times.