Daytime darkness

The heat here in The Hague is 30C+ this week and since very few homes here have air conditioning (it's never normally this hot), I'm looking on the Internet for ideas to keep the house cool. Many say to close all windows, blinds and curtains during the day to keep the heat out. I personally find this makes the house very stuffy but we'll see as the week goes on. We have a table-top fan but that's not making much difference. I'm not too bothered about how uncomfortable T and myself are, I'm more concerned for Heidi-cat. She's just been pretty lifeless, sprawling out and looking for cool-spots all round the house to lay down in. She's also being sick several times per day. Last year, I bought her 3 cool mats but she never lies on them (I don't think she likes the plastic covering on them) even if I cover them with one of her blankets. So I've taken to putting cool-box ice-packs under her bowls of water, putting ice-cubes in her water bowls and giving her frequent wipe-downs with a cold, wet cloth. The temperature is supposed to go down to the mid-20's by Friday so hopefully she will be better then.