Originally Posted By: jnosworthy This post was automatically imported from our archived forum.
I’m using the calculation of computing minimum foundation ventilation as : heated square footage time 1.5% is minimum quantity recommended. What other formula’s are out there floating around. Any opinions are welcome
Originally Posted By: mboyett This post was automatically imported from our archived forum.
I’m assuming you are referring to an under-floor situation, i.e. a crawlspace. If so, the 2003 IRC specifies 1sf vent/150 sf of space (.67%) with one of those vents being within 3’ of each corner. This number changes depending upon how the crawlspace is built, i.e. vapor retarder, mechanically vented, etc.
Originally Posted By: jnosworthy This post was automatically imported from our archived forum.
Mike,
Thanks for the feedback, and sparing me possible egg on my face for the second time this week. You assumed correctly that I was speaking of an area over a crawlspace. The house is 9 months old, has 12.44 sq.ft. It looks adequate. Your method says it needs 12.66, while my “rule of thumb” would have suggested it requires 28.5 sq ft. Big difference. How much more can you factor down for having 6 mil poly ??
Originally Posted By: mboyett This post was automatically imported from our archived forum.
You should be able to wait till it loads, maximize the page, then position your cursor in the bottom right side of the page, near the page number and then an icon should appear that will allow you to “Expand to Regular Size”. That might or might not work for you. Give me a little time & I’ll re-scan it and try to put it into a pdf file later this evening & repost it.