I recently looked at an older home that has a yard which slopes down from back to front. The crawl space vents on the back of the house are below ground level and the vents in front are above ground level. Rain water will run into the vents in back but will not come out in front as the front vents are above ground and there are no drain holes. I believe that water trapped in the crawl space would create condensation that will eventually rot the floor joists and sub-floor. Any ideas on how to remedy the situation since it is an older home built in the 70’s?
Crawlspace vents are for air flow not water flow. Crawlspaces ideally should always be dry and the vents should be above ground level. My advice is get a good home inspector to help you before you spend your money.
Sounds like the rear yard needs to be regraded if possible. Have you been into the crawl space to see if water has been getting in?
Water always flows downhill. So regrade, drains, gutters. Or a combination of these.
As Randy stated, crawlspace vents are meant for for air flow, not water flow.
It sounds like the grade should be lowered in the back, you should have at least 6 inches between the grade and the top of the foundation walls with a slope falling away from the structure of a half inch, per foot, for 10 feet, if possible for site drainage.
If water has been flowing through all these years, there’s a good possibility there will be structural damage. Be sure you hire a good inspector, he could save you from a potential nightmare scenario.
In saying this, crawlspace vents have been proven to be ineffective and the building science has changed concerning crawls.
http://buildingscience.com/documents/information-sheets/crawlspace-insulation
Thanks for the reply. Appreciate it.
Thanks for the reply. I considered regrading and adding drains, gutters but decided it would not be worth the extra cost.
Thanks for the reply. I thought as much and we decided to pass on buying the house.