MyFloridaCode.com

In 1972 I had a office I rented in a small strip center in Connecticut. The 
rear exit was a 5' wide by 3' deep wood landing with stairs to the ground 
12' below. It overlooked a small stream. My cousin and the girl from the 
office next door use to flirt with each other out there. One day I came in 
and walked out to say hi. As soon as my additional weight was added to the 
landing the whole thing went down into the stream. The girl broke her arm 
and never talked to my cousin again. I had a few punctures from rusty nails, 
and my cousin just got wet.

Afterwards we looked to see what had failed. There was aluminum head 
flashing still attached to the wall. The 20 year old PT ledger was somewhat 
rotted but did not fail. It had a sort of end flashing but there was no 
shingle overlap with the head flashing. Rot damage was primarily at the ends 
of the ledger. The 5/6" x 3" lag screws were well rusted but still 
servicable however they had all pulled right out of the ring joist. Enough 
moisture had worked its way under the ledger from the ends and around the 
lag screws to rot out the lag screw conection to the ring joist.

Whenever I have a exterior wood connection to a home I think of that wood 
landing that fell. You must keep the moisture out. It doesn't take extra 
cost you just need to flash it properly. I think you would be crazy to 
attach the ledger to the stucco. There is just no way to properly fash it.

Saw cut out the stucco for the size of the ledger. Use a putty knife to make 
sure you can slide at least 1 1/2" to 2" of aluminum flashing up under the 
top and sides of the stucco. If fasteners are in the way, just make your saw 
cut larger and plan on a stucco patch. Use to be you could get a 5000 series 
aluminum but today all that is available is 6061, if your job is near the 
shore use stainless flashing as 6061 is next to useless in salt conditions. 
I would start by installing 1 1/2" flashing at the bottom stucco cut with a 
turn out at the two corners to divert water, then cover the cutout area with 
Grace Ice and Water Shield. Slide in the head flashing and end flashing, 
attach the ledger, attach a strip of aluminum as a drip edge to the bottom 
of the ledger, then bend the head and end flashing over the ledger, shingle 
style. Cover the whole flashing / ledger assembly with a layer of Grace Ice 
and Water Shield. Use hangers to attach the joists. I would use coated or 
stainless screws to assemble the deck.

If the deck is to be water tight, the head flashing would be a simple "L" 
attached to whatever surface membrane your using.

The hardest areas to flash are the 4 corners of your ledger and the ends. 
You must overlap the head flashing such that the end flashing is counter 
flashed. Adding a turn out to the bottom corners to divert water flow is 
also a must but there just isn't a good way to seal the ends that doesn't 
rely on caulk.

Good Luck,

Alex Koskey, Pres.
Koskey Corporation, Inc.
Florida Lic. CBC1250552
Cell: (850) 585-7883
Fax:  (850) 654-9812
E-Mail: AKoskey at cox.net
Web: www.KoskeyHomes.com