Correction for coverage of window on Man J

david_caryJune 1, 2011

So I was looking over a man J calc. They have all my W facing windows with the same multiplier. 3 of the windows are facing a covered porch - like 12 feet deep just a foot above the windows. I don't feel like I ever get direct sun on these windows and they act more like a North facing window from a cooling standpoint. They wind up being the same btu/hr/sqft as uncovered windows which clearly isn't right.

Is there a way of correcting this that I don't see? These windows add up to 5000 btu/hr despite being low-e.

There are just so many ways to fudge manual J's. Does anyone know about what a 10 sqft West facing low-e window (shgc of .3) equals in btu/hr in NC?

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Good information to know! I am suppose to have my load calculation on tomorrow, so I look it over really good. I just fired my HVAC who could never produce a Manual J for me. I guess he was using square footage. Luckily for me I'm using a energy rater who requires it. So its kind of like a checks and balance for me.

Sorry I don't have any information to give you.

On a side note-- I have followed a lot of your posts and our home is similar in size (also doing an unfinised walkout) Just read today that you used M&W windows as well.

    Bookmark   June 2, 2011 at 1:07PM
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