WindowWise blog
Plain-English articles on opening windows for energy savings + comfort.
The physics of natural cooling
Where natural cooling actually works (and where it doesn't)
You've heard the advice: open the windows at night, close them before the heat hits. Free cooling. It's mostly right. But "mostly" is doing a lot of work — there are climates where…
What is diurnal swing?
If you've read anything about natural cooling, passive design, or whether opening your windows actually saves energy, you've probably seen the term "diurnal swing." Or maybe…
The math of natural cooling
If you have a building-science background or just like seeing the numbers behind a claim, this post is for you. We're walking through the thermal model WindowWise uses internally…
How much can window-cooling save you?
Short answer: somewhere between $50 and $300 a year for most US households in climates with a meaningful daily temperature swing. The exact number depends on five things you can…
Smart thermostat vs window-cooling: where do the savings actually come from?
If you've been quoted "save 10-23% on heating and cooling with a smart thermostat," you've heard one of the most successful pieces of energy-marketing copy of the last decade. It's…
Weather signals beyond temperature
Should I open my windows during wildfire smoke?
The short answer first, because that's why you searched. If the AQI in your area is 101 or higher, keep your windows closed. Don't open them at night, don't open them for a few…
Pollen season + open windows
If you have seasonal allergies, you've probably been told to keep your windows shut from April through June. Maybe longer. That advice is half right and half a missed opportunity.
Why opening windows on a "cool" humid night makes your house feel worse
You've probably lived this one. It's August in Houston. You check the thermometer at 4 AM — 76°F outside, 82°F indoors. Cooler outside than in. So you open the windows, expecting a fresh breeze.
The window you've been opening on the wrong side
Open your windows on a breezy afternoon. Stand in the middle of the room. Notice anything? For most people, the honest answer is "not really." A faint stir near the window, maybe a…
How to use your phone's 30-minute rain forecast for fresh air on rainy days
Most people in rainy climates have a habit: when it's raining on and off, they leave the windows closed for the whole day. By hour 36 the house smells like yesterday's dinner, the…