I'm an Italian architect and I'm planning an experimental bioclimatic nZEB for Mediterranean climate with high thermal mass  and capacity internal, (inertia between 13-21 hours), superinsulation with Periodic Thermal Transmittance< 0,002 W/mqK  (U-values wall= 0.13 W/mqK, U-values roof= 0.18 W/mqK, U-value ground floor = 0,30 W/mqK,  U-value of windows: 0,80 W/mqK), automatic shading and sunscreens, construction without thermal bridge, good air tightness, etc. But I have great doubts about the mechanical ventilation heat recovery balanced flow for the following reasons:
1) the lack of sustainability of the MVHR system (footprint and CO2 emissions): I can recommend the book: http://www.sciencedirect.com/science/article/pii/S0378778812002071
2) from some research I've done, there is some risks to health in passive house with MVHR: the air flow that passes from the channels and the filters causes poor indoor air quality and increased of bronchitis, tiredness, frequent colds, etc): I can recommend  a research about this:
3) the real efficiency of heat recovery systems: the user doesn't keep the air-filters completely and regularly cleaned with consequent losses of load;
4) in warm climate I don't think that is short the return on investment (because  I have to install also an air conditioning systems for the summer);
5)  there are some research in Mediterranean climate zones or warm climate area (Passive-On, Passive House California standards, etc) which don't exclude the use of conventional mechanical ventilation without heat recovery.
For these reasons I  thought of using  a little heat pump  (heating-cooling air/air or air/water no radiant flooring but multi-split with solar panel and photovoltaic) combined with conventional mechanical (exhaust) ventilation with natural inlet functions, without heat recovery (CV): ie a single-flow ventilation in which the intake of air takes place via simple wall or windows fresh air inlets (hygro-adjustable no channeled easy to clean ),  while only the extraction duct is channeled and connected  to an extraction machine. (type bahia compact- microwatt Aldes). 
Can give me some examples of Passivhaus buildings, in warm or temperate climate, without heat recovery system?
Do you know some indipendent or epidemiological research about the quality of MVHR air and CV air?
Hoping for your help !!!

Tags: MVHR, Mediterranean-climate, Passivhaus, casa-passiva, heat-recovery-system, high-energy-efficient-Buildings, indoor-quality-air, mechanical-ventilation, nZEB, natural-ventilation, More…net-zero-energy-building, passive-house

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