Rain Rain go away

Raining in crawlspace 2 contributing factors

  1. vapor barrier not present
  2. no vents present
    Question I forget and I don’t have my books with me to look it up, what is the proper ventilation for a given square footage.

No answers to Brian’s question from anyone.

Are you talking about foundation crawl space or attic crawl space?

Here’s one opinion and a link to more complete info.

*A rectangular crawl space requires a minimum of two vents, located no farther than 3 ft. from corners. The vents should be as high on the wall as possible to best capture breezes, and landscaping should be planned to prevent obstruction of the vents. The total free (open) area of all vents should be at least 1/1500 of the floor area. In the absence of a ground cover, the vent area should be increased to 1/150 of the floor area. Ventilation alone should not be relied upon where soils are known to be moist.


and another


Thanks for helping us here, Michael.

Thanks for the calculation. I have a 20’x12’ crawl space, no vapor barrier, My numbers I come up with is 240sqft divided by 150 = 1.6 what size opening does this then require? And we need atleast 2 so do you divide by 2? And Ray thanks, I see your from the west coast, if you ever want to come to the east coast I’m from York just south of Harrisburg, PA, near the Amish country of Lancaster and Gettesburg battle fields, let me know I can put you up for free.:wink: :wink:

Cool. However, I always travel with my two companions, Ms Margarita and Dr Cuervo. Do you have room for three? :margarit: