When we bought this house, it needed a new roof and I don't just mean the shingles needed replacing. When we chose the trusses we went with a 36" overhang for the eaves to help shade the windows on hot summer days.
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But for now, we open the windows when the outside air cools down and turn on the whole house fan in order to pull the cooler air inside. Then, during the heat of the day, we keep windows and doors closed and draw the blinds so the house maintains that coolness. Every room has a ceiling fan that we can switch on as needed, too.
So it gets hot -- sometimes the steel front door is hot to the touch on the INSIDE, but unless the humidity goes above 60% or so it doesn't feel any worse than it might if we ran the central air. I think it's even better because in previous years (this is the second summer for our "no a/c" policy) when we'd break down and turn on the air, many nights it would be cooler outside than in since we set the thermostat high (78º or 80º) to conserve energy and money.
This is the second house we've put a whole house fan in. I grew up with one my dad had purchased thru the Sears catalog so I knew how effective they can be. DH was willing to give it a try at the other house and then, when we moved here, it was one of the first things he worked on. And considering how much work this house needed, that says a lot. If you're looking at ways to reduce the cost of cooling your house, consider a whole house fan. They're relatively inexpensive to buy, easy to install and cheap to run when compared with the A/C. Drawbacks? Can be noisy, check out the sound levels as it varies between models (direct drive vs. belt driven).