One of my friends was looking to cool down his screened porch, so he came to me knowing I had some bacic physics knowledge and might be able to help.
read more- [ ] We've found a lot of people talking about roof vents. We read about one person who tried to do what you suggested with the cross ventilation near the roof, and they said it didn't work unless you were standing in the flow of the air (which is what Joe had anticipated when we first thought about your suggestion). - [ ] Could ceiling fan placement/speed be improved? It seems to us as though the best bet for staying cool is to have air blowing directly on you all the time. Can you also confirm that the direction of the ceiling fans is correct? - [ ] We explored evaporative coolers, which appear to be well suited for a situation like this. But it became clear that this was only for climates that are much less humid than NC. So this isn't a good option. - [ ] Shades are an option, depending on how much direct sunlight you get. But it's not preferred because you obviously want to be able to see outside and feel like you're part of the outdoors on a screen porch. - [ ] Before committing to anything, we think you should see if there's a way to test it. For instance, for your idea, you should have two ladders or otherwise temporarily affix a box fans to the ceiling so that you can see if you have any effect after running them for a while. A/B test, so try it with and without the fans running. For this test, the direction of airflow might matter, so you might want get fans that would allow you to test both directions. You can also A/B test your "items from the freezer" idea, but we think that's going to be very difficult to keep up and don't anticipate it having enough of an impact. One very unfortunate thing is we're not sure how you could test the roof vents idea without actually installing them, which is unfortunate. - [ ] We talked to our friend last night who works in construction and he also thought that the roof vent would be a good thing to try, he also thought that your idea of the cross ventilation near the roof is worth a try too. He said that the house probably stays a lot cooler on a 72 degree day with no A/C compared to the porch (which is very hot) because the house is insulated, so it takes more heat + time for it to heat up during the day compared to the porch, which will heat up more quickly. He said he would also consider insulating the roof, which we've seen others say is a good idea too. He said he would ask his friend who has done historical renovations in NC for about 40 years what he thinks. - [ ] Ultimately, I think the best thing to do is ventilate the roof (e.g. ridge vent, roof vent) + add insulation to the roof. What's probably happening right now is the roof is getting really hot, and then your ceiling fans are blowing the hot air from the roof down onto you.