once and for all, flash a deck properly!
stevehoog
| Posted in General Discussion on
Is this deck flashing done properly? I do not want to start framing until I am confident it won’t leak (I had to tear the old deck down and replace sheathing). If you look closely at the picture, there is an opening in the corner. It looks like two pieces of flashing. If it is only one piece..why tuck it behing the ledger? I thought the idea was just to bend it down and over the whole thing (seamless)?
http://i761.photobucket.com/albums/xx259/stevehoog/flashing.jpg
Replies
No you are right, that looking like a leak sooner or later. I'm also not keen on how small the drip in on that flashing. Good chance once the joists are on it will be bent back.
Are the joists the same depth as the ledger? If they are, have you thought out a detail for how water hitting that flashing gets past the first piece of decking installed against the siding?
yes the joists AND the ledger will be 2x10 lumber. It looks to me like I could still tuck a flashing in the over top of what is currently there. This one would come out over top of the ledger and a few inches down the front of it. Im not sure why you would even think about leaving ANY kind of opening where the top of the ledger meets the house, even if it does bend behind the ledger and come back up. Why can't I find a builder who will get this right...or am I the one who is wrong?
I don't know, this is why I hired a builder to do this part of the deck construction. I do not want to have to tear this one down too.
How are you gonna flash that inside 45 degree corner seamlessly with one piece of flashing with no cuts in it? He probably used one piece but sliced it so the folded part overlaps itself... gobbed some silicone under the joint. I say it looks alright.. not the prettiest. but I don't think water will get behind the ledger (assuming the flashing tucks up behind the siding).
"How are you gonna flash that inside 45 degree corner seamlessly with one piece of flashing with no cuts in it?"
Easy. Cheat -- by using copper and soldering the joints.
With all the corrosion issues associated with PT, that's all I'll use to flash the stuff anyhooz.Mike HennessyPittsburgh, PAEverything fits, until you put glue on it.
" "How are you gonna flash that inside 45 degree corner seamlessly with one piece of flashing with no cuts in it?"
Easy. Cheat -- by using copper and soldering the joints."
I had a feeling someone was gonna say that....
That's not flashing; that's a couple of pieces of aluminum drip-edge for roof eaves, flipped upside down and mashed sorta flat. It is actually worse than useless: the hem and creases in that drip edge will hold water rather than shedding it.
The way to flash the deck ledger is with some serious metal, say 26ga galvy, bent so it runs down the wall for the full height of the joists plus three inches, then across the top of the ledger, and down over the face of the ledger with a hemmed 45º kick.
View Image
The flashing should be bedded in pitch, or better yet, laid over strip of I&W membrane.
Dinosaur
How now, Mighty Sauron, that thou art not brought
low by this? For thine evil pales before that which
foolish men call Justice....
Never seen anything like that.
Is that the way you actually build?
What holds joists on the ledger?
Do you nail/screw through the flashing into the ledger?
That 5 degree angle cut on the joists looks like a place to trap debris rather than drain.
Do you put blocking between the joists?
Like I say, very unusual, would like to hear more of the details as to how this is actually better than the conventional way of joists being hung on the ledger with joist hangers.
What holds joists on the ledger?
Do you nail/screw through the flashing into the ledger?
To answer those questions in order, (1) two toe nails; and (2) yes, which is why I specified the flashing should be bedded in pitch or laid over self-healing roofing membrane stuck to the wall and ledger.
What I do shunts water away from the joint between the house wall and the ledger board. That joint is where the serious, expensive, disastrous rot happens that threatens the house itself. To help protect the end grain of the deck joists, I put that 5º 'skash cut' as Mike Smith called it on so no joist end will trap and suck up water running down the face of the flashing. Yeah, it might collect some debris...but not much if the first piece of decking is set properly.
Finally, Yes, you need joist-high blocking.
Dinosaur
How now, Mighty Sauron, that thou art not broughtlow by this? For thine evil pales before that whichfoolish men call Justice....
steve
It looks like they used aluminum flashing. The treated lumbe will quickly corrode thru aluminum or galv unless you use a divorcing membrane like peel and stick or tar paper. I don't like the silicone in the corner either. The leg going down is only about 1/4" and that is not enough.
In the following link you can see how I did it. I&W behind the ledger. Peel and stick roofing membrane on the treated then 24 gal galv metal with a 1 1/2" leg going down. Then I put SS washers under the 1st deck board to help with drainage and tilt the 1st deck board slight out.
Later in the thread shellbuilder has another perhaps better plan.
http://forums.taunton.com/tp-breaktime/messages?msg=113816.3
Rich
Rich--
I hope to heck you kept those SS washers out of contact with the galvy; they don't like each other at all. Never put stainless in contact with galvanised.
Dinosaur
How now, Mighty Sauron, that thou art not broughtlow by this? For thine evil pales before that whichfoolish men call Justice....
thanks guys. I knew this didn't look correct. Dinosaur - in your pic it looks like the deck joists are "resting" on the top of the ledger board - please forgive me I have never built a deck. I guess Im getting a bit upset that I paid a man 900 bucks to prepare this ledger after a small re-sheathing and adding tyvek, yes, this house has vinyl with NOTHING but OSB behind it...should I just sell it ASAP? It sounds like I will already have to remove the ledger that was just installed TODAY and redo it.
Cargin, is it okay to put fasteners through these membranes you added under the ledger board? Does this compromise them?
steve..... your picture is too close up... where's the long range view ?
Dinosaur's method is very unconventional and problematic
there may be nothing whatsoever wrong with what you have but it is really impossible to say from that pic
is the finished deck the same elevation as the interior floor ?
where do you live so we can make a judgement about your climate ?Mike Hussein Smith Rhode Island : Design / Build / Repair / Restore
I don't know why, but almost everybody gets this wrong. It's simple:
A ledger is called that because it creates a 'ledge' upon which you set the joists. This is the best and least complicated way to attach a deck to a house wall. But remember: You do not nail or hang joists from the face of a ledger. The top of the ledger board has to be mounted to the house wall at joist-depth + decking thickness below the level you want the surface of your deck.
If height restrictions dictate that you can't place a ledger below the joists, then you need to bolt a rim joist to the framing of the house wall, and toe-nail your joists to the face of that (or use joist hangers). Flash the entire face of the rim joist over I&W membrane, and nail through it to attach joists. Best to use joist hangers for this situation so you can make that relief cut on the ends of the joists.
Much better than using a rim joist in cases where you have not enough height for a ledger, you should think about supporting the deck framing independently of the house. That way, you don't need any flashing.
Dinosaur
How now, Mighty Sauron, that thou art not broughtlow by this? For thine evil pales before that whichfoolish men call Justice....
In nearly twenty years of construction I've never seen a deck actually use a ledger. In this neck of the woods it's always a rim joist (though always called a ledger). At ground floor, to do a true ledger you would have to mount it to the foundation.I agree that the best practice is to make it free-standing. But you know how much people love digging 4-foot holes.Steve
In nearly twenty years of construction I've never seen a deck actually use a ledger. In this neck of the woods it's always a rim joist (though always called a ledger). At ground floor, to do a true ledger you would have to mount it to the foundation.
So? What's so hard about lag-bolting a ledger to a foundation wall? It's a helluva lot less trouble than finding mis-spaced studs behind the sheathing, IMO....
But I hear where you're coming from. In remods and 'deck disaster' calls, I see mostly rim-joists, too. Please note that that doesn't make it good, just common.
The reason a lot of decks are built with rim joists around here is they are built on the ground, as cribs, and then the frame is hoisted up into place as a single unit and the rim joist is nailed (yes, nailed, in most cases) to the house wall and a couple of 2x posts are stuck under the rim joist as 'insurance'. Real garbage construction...but it's fast and cheap and the guys building decks that way are all working on flat-price quotes.
The problem with using rim-joist construction for a deck is that flashing it is a cast-iron bitch (most of the decks I get called to see were never flashed at all; they used PT and skeedaddled).
Most people who build these abortions don't even understand what the flashing is supposed to protect, so they don't do it properly (or at all). What I see ranges from nothing to a strip of handy-coil alu stuffed up under the vinyl siding and kicking out on top of the deck boards. That's about as useless as teats on a bull, but the poor bastard HO doesn't know any better, and thinks his 'contractor' has done him right.
The flashing on a deck is there to protect the house wall, not the deck itself. There is no way to protect the deck (except to cover it with a roof, of course); the best one can do is top the joists with membrane or 100# and pitch, use HDG or stainless fasteners, and make damned sure the decking is laid heart up. All that slows rot by promoting good drainage and avoiding rust-rot at fastener penetrations. But in the grand scheme of things, the deck is considered disposable. The house, OTOH, is not. That's why you flash the ledger (or rim joist) to keep water from getting behind it and rotting out the sheathing and house framing.
Flashing a ledger is easy; my drawing in the earlier post shows how to do that.
But, to flash a rim-joist, the flashing has to run across the top and down the face of the rim joist, and the joists are toe-nailed (or joist-hangered) through the flashing into the rim-joist. This means there are lots of penetrations, which obviously ain't a good thing. (It also means the crib can't be built on the ground; the rim joist has to be bolted to the house framing, then flashed, then the joists have to be placed. Another reason a lot of quickie-decksters don't bother with flashing or bring it out on top of the decking.)
In addition, to do a drainage cut on the wall-end of the joists, you have to use joist hangers (which cost extra dough and take time to install properly). Without that 5º relief, the joist end sits flush up against the flashing, trapping any water that runs down its face and sucking it up into the end grain. Hmmm. I don't think so, Tim....
I agree that the best practice is to make it free-standing. But you know how much people love digging 4-foot holes.
Yeah, LOL. And around here, it's 5 feet, or until you hit the Canadian Shield, which ever comes first....
Dinosaur
How now, Mighty Sauron, that thou art not broughtlow by this? For thine evil pales before that whichfoolish men call Justice....
bs.... you can hang joists on joist hangers from a LEDGER
what keeps your joists from overturning if you have that skash cut on them ?
View ImageMike Hussein Smith Rhode Island : Design / Build / Repair / Restore
you got a permit for that concealed hanger? :)
what software did you make that with Mike?
i copied it right off a website
the back flash and counter flash is part of our normal procedure
and keeping the deck finish elevation 4 " - 6 " below finish floor when possibleMike Hussein Smith Rhode Island : Design / Build / Repair / Restore
I agree 100% on the backflash. I call it counter flashing but not sure that term is appropriate though.
Great drawing! Now if you were to rip the top of that rim joist at about 15 deg and use custom "Z" metal you would have it. Or as posted earlier, rip 3/4" off the rim joist, but I prefer to have the 15 deg. slope on the top of the rim.
Recently I had occasion to visit a house I built in 1983. 2nd. story deck , done as you drew but with the 15 deg. slope modification. All PT framing, red cedar decking. Lagged to the house rim joist ( added blocking behind the house rim where lags were to go). Second "Z" metal starts behind the flashing at the bottom of the deck rim and allows siding to be protected below the rim joist. Decking needed replacing in some spots, but the deck structure was perfectly sound and the house shows zero signs of water penetration at the deck/house juncture.
May not be a life time but 26 years worth of Rainy Oregon weather and it is still sound.
They can't get your Goat if you don't tell them where it is hidden.
I know you work hard at being a dinosaur and all that, being proud of the olden ways, but your ledger detail creates more problems than it solves. As Mike shows it is perfectly acceptable to use hangers.
Welcome to the Taunton University of Knowledge FHB Campus at Breaktime. where ... Excellence is its own reward!
Paul, you didn't read my post carefully enough; I actually suggested using hangers when you have to build the deck on a rim joist because there's not enough height to use a ledger.
I don't like hangers much, but they come in useful sometimes and that situation is one of them.
Dinosaur
How now, Mighty Sauron, that thou art not broughtlow by this? For thine evil pales before that whichfoolish men call Justice....
hangers avoid the need to poke holes in that flashing. you are depending on the 'pitch' or whatever sealant you are using under that to keep water out, not a good primary plan
Welcome to the Taunton University of Knowledge FHB Campus at Breaktime. where ... Excellence is its own reward!
"custom "Z" metal"
Is that where you put it face down on the garage floor and step on it?
:-)
Dang man You been spying on me?? I actually use a sheet metal shop to bend a lot of stuff, they do a neater job.
They can't get your Goat if you don't tell them where it is hidden.
I bought that used Tapco 10' brake last year, and while not mastery, I have bent some z metals, pan flashings for windows and doors, a skirt to cover up some foundation foamboard, and a belly band cap!
But mostly it sits in the backyard...
enjoying our weather?
I thought about buying a small brake for years, just never could justify it, although I probably have spent 10 x the cost of one on custom bent flashing over the years. Weather? I was up in Wenatchee Wa. for the last 4 days. While it wasn't unbearably hot, I will take our weather over the heat there any day .
Nice trip though, watched a friends son play ball with his American Legion team and then watched him ump a couple of Little League games.
More baseball than I have watched in 40 years! Good Time , no worries, just kick back and watch the kids play their hearts out.
They can't get your Goat if you don't tell them where it is hidden.
what keeps your joists from overturning if you have that skash cut on them ?
Blocking, what didja think? I'm way too lazy to put cross bracing in every joist bay....
Mike, I never said you can't hang joists from the face of a 2x; I just said you can't call it a ledger. What I'm doing is I'm insisting on the terminology. There's enough confusion in the business already; we don't need any more. If a hunk o' wood creates a ledge that's used to support another hunk o' wood, it's a ledger. If it doesn't, it ain't. I don't care how many badly-edited construction books are in print that say otherwise.
Dinosaur
How now, Mighty Sauron, that thou art not broughtlow by this? For thine evil pales before that whichfoolish men call Justice....
dino... the rest of the world and all the codes call it a ledgerMike Hussein Smith Rhode Island : Design / Build / Repair / Restore
>>the rest of the world and all the codes call it a ledger<<When in Rome...We have a small town near here...spelled Cairo...pronounced care-oh. Used work near a town spelled Buena Vista...pronounced Byew-na vista.Realtors call everything colonial...Nobody gets muntin/mullion right...(except me <g>)Steve
Nobody gets muntin/mullion right...(except me <!---->)<!---->
So, that's funny. Because I went to wiki the definitions, and right there on the muntin page, they list this as an example.
I see plenty of mullions there, but not a muntin in sight. Maybe I'm confused? You can see the full photo here
View Image'Man who say it cannot be done should not interrupt man doing it' ~ Chinese proverb
View Image
mulled is a verb...
muntined ain'tMike Hussein Smith Rhode Island : Design / Build / Repair / Restore
I had mulled that over, but I'm glad you, erm, muntined it!'Man who say it cannot be done should not interrupt man doing it' ~ Chinese proverb
View Image
the rest of the world and all the codes call it a ledger
And since when is that a recommendation???
Oh, boy--now you gone and lit ma fuse!
Mike, large groups of people and official/semi-official bodies get things wrong all the time. For instance, the Boy Scouts taught generations of youngsters to use a square knot the wrong way (and not incidentally put their lives in danger by so doing). I don't for a second question the good will or good intentions of the BSA...but you know with what the road to Hell is paved.
If you allow 'people' to call something by the wrong name for long enough, eventually people wind up having precisely the argument we are currently having. Tolerating sloppy communication sows confusion; it also degrades the precision of the language.
It doesn't just happen in English, either; the last four weeks I've had an apprentice roofer working for me who keeps referring to 'dormers' as 'gables' (in French, of course) and vice-versa, because the sloppy local slang usage has blurred the distinction between those two words.
Got any idea how much time I've wasted over the course of the month trying to figure out what he is talking about at any given time...?
Oops. Gotta go; big T-storm just hit and we've lost electrical power. Hah! finally I'm getting $$ value for that UPC unit I bought for the computer after it fried the power supply last winter.
Back Later, I hope. I wanna ask Paul how to attach a joist hanger without using nails....
Dinosaur
How now, Mighty Sauron, that thou art not broughtlow by this? For thine evil pales before that whichfoolish men call Justice....
Ok,so it's not a ledger. But "Rim Joist" already describes the piece behind it under the sheathing, so how do you differentiate between the two?
"Rim Joist" already describes the piece behind it under the sheathing, so how do you differentiate between the two?
In a new construction, I can see the possibility of several different rim joists being exposed at one time, but in the usual case of a deck add-on or re-build, it doesn't seem likely there would be any confusion. However, if I needed to, I could specify the structure of which the rim joist in question formed a part. "Main floor rim joist" or "second storey rim joist" or "verandah rim joist" or ....
If you want to have some fun, take a look at an old architectural elements or moulding catalogue. There are precise names for every individual element you can imagine, and then some. It's absolutely fascinating. But many of the names have fallen out of usage, even among professionals, and those that remain in the lexicon are frequently abyssmally abused.
As I said in another post, this phenomenon isn't limited to English. I work in French most of the time, and I see the same thing happening. For instance, people don't talk about moulures ('mouldings') anymore, they talk about quart-de-ronds ('quarter-rounds'). So you'll hear somebody telling a carp to go put some 'quarter rounds' on that door....
On Thursday I was at the yard placing a large order for 2x2 clear cedar balusters (350 pieces). The yard's inventory system showed 400 pieces in stock, but when I got out to the shed, they only had 35; the rest were 'patio grade' (which is to say #2 & 3). At the price I was paying ($4 a piece) that wasn't good enough.
First, nobody understood the distinction among 'clear,' 'select,' and 'patio.' I had to specify that 'clear' (which is what was on my invoice) meant 'clear of knots'.
Next, the buyer started calling around to find me some clear balusters (which in French is 'balustre')...but he kept asking his suppliers for 'barratins'. (A barratin is a little tune or rhyme that one sings or hums over and over.) I listened to him on the phone; it was like hearing one of those old Bob Newhart telephone routines.
"Yeah, that's right, I need 300 clear red cedar barratins up here by tomorrow.... No, barratins! .... What? .... Barratins! you know, 2x2x42 inches with both ends cut off on a slant...."
Since French is my second language, I wasn't dead sure that barratin might not have a second meaning of which I was unaware, so I asked one of my guys when I got back to the site. French is his mother tongue, and he's got a better than average formal education for this area, so he's usually a pretty good source for me when I'm in doubt about something.
'Barratin? That's like a children's rhyme for skipping rope, or nonsense syllables for dancing an old-fashioned reel or jig. Da-da-dee, da-da-dah.... You know, like that. Who was the buyer?" he asked.
'Jocelyn,' I answered. 'The tall guy with the red hair.'
'Oh,' he laughed. 'He's from Lac St-Jean. That explains it....'
Dinosaur
How now, Mighty Sauron, that thou art not broughtlow by this? For thine evil pales before that whichfoolish men call Justice....
Dino, great story, and it is a good thing to pass on correct terminology. It just makes it easier to communicate effectively, if nothing else.
But I have to disagree with you on "ledger." Language is a living thing, and it has evolved to the point where pretty much every carpenter out there knows what you mean if you tell him to install the deck ledger. Maybe it's because we don't use true ledger boards as much anymore, with joist hangers taking their place. I don't know. But I do know that if I asked any carpenter out there to install the rim joist for the deck, he'd be out on the other side of the girder, and certainly not at the house wall.
And some old words just don't have any meaning any more, but there usage remains.A while back I posted thread in the tavern about that. One example is "don't post large pictures, I am on a dialup modem."The dial is long obsolete. But, at least to this generation it still has a meaning. I suspect that it will be still in use a few more and no one will know what the orginal meaning is..
William the Geezer, the sequel to Billy the Kid - Shoe
Language is a living thing,...
So is cancer. If you keep it under control, it won't kill you. But it you don't....
;-)
This subject is worthy of its own thread, tho it might very well wind up in a Tavern flame war. Language preservationists and proponents of a 'no-rules' evolving language don't get along much better than the religious right and radical feminists....
Dinosaur
How now, Mighty Sauron, that thou art not broughtlow by this? For thine evil pales before that whichfoolish men call Justice....
Why with screws, of course!
Tu stultus esRebuilding my home in Cypress, CAAlso a CRX fanatic!
Look, just send me to my drawer. This whole talking-to-you thing is like double punishment.
bs...
ledger board
n.
1. The top railing of a fence or balustrade.
2. A narrow horizontal board attached to a row of studs to support the ends of floor or ceiling joists. Also called ribbon.
Mike Hussein Smith Rhode Island : Design / Build / Repair / Restore
There are a few reasons why I do not put the flashing underneath the deck. It traps leaves and also creates a dam for water by the presence of the deck board. If water is trapped by the deck board then the water cannot escape underneath the board because it is pinched between the deck board and the rim joist or ledger. For years I have been flashing the building so that the water comes out on top of the deck and for 27 years now have never had one leak.
The OP's ledger sure doesn't look to be PT.
"I do not put the flashing underneath the deck. It traps leaves and also creates a dam for water by the presence of the deck board. If water is trapped by the deck board then the water cannot escape"
That's why I use a ledger that is 1 1/2" shallower than the joists. The first piece of decking overhangs the joist leaving a 3/4" gap. Nothing is trapped.
I can see where that would work better than being trapped by the first deck board unless leaves piled up and got down under the first deck board. I have seen water travel back into a home through the joists underneath and that is also another reason why I flash the top of the deck and not underneath the deck. In effect what I am saying is doing the flashing much the same was if the edge of the deck were one big shingle.
kinda hard to make it seamless on the 45°. That flashing doesn't do much if any to keep the water from getting behind the board. I'd pull off the lower row of vinyl and the j-channel and redo it.
eta and I'm wondering about he screws and nails they used too. The screw looks suspect.
Edited 6/25/2009 6:51 am ET by john7g
Nice drawing, John. That's my general approach.Question: is copper in contact with PT OK? What's with the rolls of really thin copper flashing with the membrand adhered to the back of it for?Steve
Thanks Steve. It's slightly dumbed down version I have.
I haven't seen the thing rolls of copper with the membrane. Where are you finding it? I'm just finally finding a reasonably steady source of lead but up 'til now it's been the AL which used to be just fine.
I'm pretty sure copper is safe on the ACQ since the C in ACQ is Copper. Stainless is fine too. The tarpaper in the drawing can be omitted if the flashing is compatable with the ACQ.
I don't know if someone beat me to it but this is why I do not attache deck to houses at all. Decks, imo, should be free-standing structures whenever possible.
I refuse to accept that there are limitations to what we can accomplish. Pete Draganic
Take life as a test and shoot for a better score each day. Matt Garcia
I'm still not at all convinced about freestanding decks. Apart from some difference of opinion over how to do it, are any of the options people have posted for flashing the ledger really that difficult to do?
I have still not had any takers for my request that someone post a picture of a freestanding deck more than a couple of feet off the ground that doesn't look like like a mess with all the required bracing. I seems like a good idea, but no one seems to be able to provide an example of one where it has actually been done.
most decks are within 3' of grade. Getting into higher decks can be more of a challenge and that is why I said "whenever possible" or words to that effect.Here is a pic of one I just did a few summers ago that was a story above grade.
<!----><!----><!---->
I refuse to accept that there are limitations to what we can accomplish. Pete Draganic
Take life as a test and shoot for a better score each day. Matt Garcia
I finally got back over to sneak in at one of them for ya. Good thing they took the limitation off the attachment allotment!
Welcome to the Taunton University of Knowledge FHB Campus at Breaktime. where ... Excellence is its own reward!
A couple more examples like that and I'd be well on my way to being a convert. I was beginning to think freestanding decks were apocryphal creatures like unicorns.
(Aside to my wife: No dear, I'm just joking with Piffin. Of course there are unicorns. I'm just unlucky not to have seen one.)
Be careful what you say there.I happen to have a unicorn in my family. very nice and never hurt anybody. He is still in the closet for the most part though. Likes tpo keep undercover because of cultural taboos.;)
Welcome to the Taunton University of Knowledge FHB Campus at Breaktime. where ... Excellence is its own reward!
Steve, I like Mike Smith's direction for the construction you had expected to to get from your contractor. Firstly, I'd definately find anew contractor, since the work you have had done so far seem to done by an unknowlegeable DIYer. First recommendation would be to buy a deck construction book and read up. Then get a recommendation from a good source, perhaps a building supply or home owner who has a deck that seems professionally done and then get references and see for yourself, the work done. Also you may ask your towns building department for their opinion, since they are the ones that will inspect it anyway, (although, there are few inspectors whose opinion I truely appreciate).
Also pay attention to not only the flashing, but materials being used, (such as pressure treated wood and the hardware that is compatable with it).
Whether you are thinking of selling your house soon or not, have a job done well, if not, you may pay a higher price after it is paid for.
Your original concerns are well founded, but your choice of contractor my have been the mistake you made. For every excellent one out there there is a botcher.
Good luck