Deck ledger attached to foundation blocks

Hi All,

I came across a deck today that had the ledger board bolted to the foundation blocks. There was no visible flashing and I researched that it is acceptable to put a bead of caulk along the top of the ledger board but that is not visible either since there is deck board installed above it. They applied a scratch coat of mortar after the deck installation and essentially sealed the bottom of the ledger board and the top of the stairs.

Does this appear to be an acceptable installation, I would think if nothing else that board would rot very quickly? Are the numerous moisture marks a result of the installation or common on mortar scratch coats and just drying out more slowly under the deck since it receives no sun?

Thanks in advance!

Do you have pics of what it looks like from above where the ledger is covered by the boards? From below it looks like flashing is missing. Biggest concern is water intrusion into the building. The bottom of the ledger should not be parged so any water could escape.

It’s hard to see since the siding is so close but the last two photos are from above, you can sort of see the mortar joints in between blocks

See page 14, etc. Pay special attention to the bolt spacing in the document.

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If the sill plate is above what we see in the last pic (above the bottom of the vinyl siding, then the flashing isn’t necessary, was it block or solid concrete foundation? if it was block, they have to be filled with concrete for ledger attachement.

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Earlier version of the same document from above:

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Looks to me that they are much to close to the edge, great catch! I will definitely add that to my knowledge bank and make sure to look out for it in the future. Thanks!

There is no way to actually 100% confirm any of those things, right? Aside from the sill plate being above the edge of the siding. As for not needed flashing, the board will more than likely rot much more quickly, especially with some of the bottom of it being sealed up with mortar right?

The ledger is supposed to be pressure treated… the flashing is not to prevent the ledger from rotting, it is to prevent water from going behind it and into the building. The bottom of the ledger should never be sealed so any water does not get trapped.

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see page 15 of Larry’s document.

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As long as the top of the P.T. Ledger is sealed and the blocks are filled, it should not be a problem.
xdeck_ledger_board_connection_6.jpg.pagespeed.ic.Z46I4QnK8t 798e4839b0b8a7bcfeb80cbd729b9ba3

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