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<DIV><FONT face=Arial color=#000000 size=2>Hi all-</FONT></DIV>
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<DIV><FONT face=Arial size=2>Thanks for answering that good, albeit simple, question yesterday. I've got another one today, that is more obscure, and one that I've run into on a number of occasions in the last few weeks, as more and more projects are asking for advice on natural ventilation feasibility.</FONT></DIV>
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<DIV><FONT face=Arial size=2>Conditioned spaces, semi-heated spaces, and unconditioned spaces seem pretty straightforward to determine. In my experience, conditioned spaces must simply meet the criteria set forth for cooling load and heating load (which is a Btu/hr.ft2 threshold, which is dependent upon the climate zone for heating load, at least). If a space has no heating or cooling system at all, or virtually no load, then the space is unconditioned. Semi heated kind of falls between the two.</FONT></DIV>
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<DIV><FONT face=Arial size=2>But indirectly conditioned spaces, where do they really apply? This is made more complicated by the ASHRAE 90.1 stipulation that naturally ventilated spaces must be modeled with a cooling system (I guess this is sort of like a hybrid system) to meet the load should your space be poorly designed. We have some people scratching their heads now that nat vent is becoming more inviting.</FONT></DIV>
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<DIV><FONT face=Arial size=2>Have I missed anything here?</FONT></DIV>
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<DIV><FONT face=Arial size=2>Sincerely,</FONT></DIV>
<DIV><FONT face=Arial size=2>Chien Si</FONT></DIV>
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