another shed project question

Oct 30, 2009 7 Replies

I have my shed almost finished.....I poured slab, then one row of concrete blocks, and then built shed....It rained quite a bit last night and I noticed some wetness at the mortar joint between slab and concrete blocks in a couple of places along one wall only. the top of the slab is at least 4 inches above grade. I guess water is passing through mortar.......Do I need to seal mortar joints somehow? any advise appreciated...


Brush a couple of coats of cementitious waterproofing, such as Thoroseal, on the outside of the block and lapping it onto the concrete. It comes in gray/grey and white.

How much of a roof overhang do you have on the shed?

R

Block walls are not waterproof. You can trowel stucco over it or you can paint it with a sealer.

That's reasonable for a shed. I was asking because I've seen quite a few sheds where there is no overhang and the lower parts of the building take a bigger beating from the weather over the years - they rot more quickly.

R

There are products specifically for concrete. I used a white sealer that contains both rubber and concrete to paint my basement poured walls. Either at Lowes or Borg. For cracks there is a caulk specific for concrete.

and use the products on the OUTSIDE not the inside. don't want moisture trapped inside the block.

nate

Does that stuff stay flexible? I'm still having a problem with water going under the block and mud and into the crawl space slab under the house. Hydraulic Cement didn't work after a couple warm/cold cycles.

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