..outdoor temperature exceeds design

ASHRAE lists cooling design temperatures at 0.4%, 1%, and 2% design conditions. That percentage refers to the percent of hours per year when that temperature would be exceeded. So, if your design conditions are the 1% number, the "hours per typical year that outdoor temperature exceeds design conditions" would be 8760 x 1%, or 88 hours (rounding to the nearest hour).

A LEED-CI project in China, with much challenges indeed. The Chinese MEP when tested general knowledge on thermal comfort design, appears to know how to navigate around the psychrometric chart but sounds unsure how to pen a narrative for submittal and compliance here...maybe a language issue. Does anybody has a simple sample narrative from a previous project, just to get the hang of it?

I'm not seeing that a narrative is required as part of the submittal requirements. Have I missed something? Typically, we just fill out the tables in the credit form, and upload Psych charts showing full and part load conditions.

Walt, sorry this was meant to be a new thread, but somehow I added to yours, not really relevant to your topic. But yes, it is true that previously we usually just composed a one page narrative and am keen to know what others are doing. Would be good to get just a sample off yours or anyone else out there, can you see my email address? Instead of a narrative, are the MEP just supposed to fill out the credit form plus pychrometric chart relevant for Shanghai climate just as Chris said above? Is that all?

A general rule in LEED Documentation is to only give the information requested. Reviewers have to review every document you post. If you post extra stuff, that means extra review time, so they get surly sometimes.

Christopher: concerning Walt's original question Does this also apply for the heating section? My weather design condition for heating is 99%, based on your calculation that means: 8,760 x 0.99 = 8,672 hrs?