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Can I apply external flashing to my exposed cinder block foundation?

jenniferz5 | Posted in General Questions on

In my Zone 5, CT, 1953 ranch house, one room is built over a slab foundation where the cinder block is exposed and damp (due to the rain dripping onto the pavers from the roof overhang).  I am waiting for a cedar planter that will cover entirely the cinder block and will serve as a rain collection vessel. 

In order to further protect that wall, would it be prudent to attach some sort of tape flashing and/or rain screen?  Any suggestions as to which one(s)?  Thanks!

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  1. user-2310254 | | #1


    I suspect the cinder blocks will dry out quite a bit once the planter goes in and the foundation is not exposed to constant wetting. I would try to create some space between the planters and wall to promote air movement.

    Probably the easiest "fix" for this issue would be to install a gutter that would reduce the amount of water splashing on the pavers. A bleach/mildewcide solution and a stiff brush or a pressure water would clean up the surface moss on the blocks--but you might need to repeat this process periodically.

  2. GBA Editor
    Brian Pontolilo | | #2

    Hi Jennifer.

    I agree with Steve on the gutters. The planter sounds nice, but better would be to use gutters to get the roof water as far away from the house as you can.

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