Passive house with hot summers

AstraMonti

How do you guys think a passive house will work in countries with very hot summers? Places like Spain, Italy or Greece they can easily reach 40+C around noon in July, August.
I 've read various articles about it and some say you ll need to incorporate a central a/c in the design while others say with detailed shading by a good architect you ll keep the heat out.

If an a/c is needed doesn't that go against the "passive house" guidelines?

sydthebeat

It would.
Over heating is an factor considered in passive design.

This is dealt with by clever design and detailing to include cross ventilation, thermally massive elements, and shading with overhangs, bris soliel etc

BryanF

why should it not perform better than an average spainish (for example) house?

You design to avoid overheating, you design for thermal mass, you design solar shading, you design in amounts of insulation that keep the heat out in summer. The occupants don't need the HRV part of the system in summer so they turn it off and they may need AC but no more than any other house, and I would suspect less than a standard house

Strolling Bones

http://passivhaustagung.de/Passive_House_E/PH_MedClim.html

good thermal protection also helps to provide high thermal comfort in summer

Calahonda52

was in Poland recently, some houses have the adjustable brise soleil as do many offices.
In Greece I have seen an extra, ventilated underneath, roof above the weathertight roof just to stop the intense solar radiation getting to the roof.

I suppose a veiled cross battened tiled roof construction would help