We have on roof PV, which keeps out a lot of heat. We also have mvhr, which automatically heat excahnges or bypasses- it doesn’t handle huge amounts of air though. We keep windows closed on hot days (house upstairs 25, outside 33C recently), then open windows at night when it gets cooler. I’m wondering about getting a ‘brise soleil’ to cut out more heat from 3 south facing windows. External blinds work well, although difficult to retrofit.
|