Avoid Disasters: How To Properly Flash A Deck || Dr Decks

hey guys Dr Dex here today I'm going to show you how to properly flash a deck some of you may not even know what flashing is or have never used it before so this is just an instructional video on why and what you need to make that happen so if you like this video don't forget click that subscribe button so what I have here is a simulated house wall and a pre-installed ledger board to the house this is where our deck's going to go and the one of the most important things that you can do to a deck it costs the least amount to do and it'll cost you the most amount of damage if you don't do it is adding flashing to your deck and what flashing does is it waterproofs the connection from your ledger to the wall so the first thing that's not done on this wall is that there's no waterproof membrane tape Behind The Ledger so what I always do on every deck build is before I mount a ledger to the wall I install waterproof membrane tape and this is wet right now so normally the house is going to be dry in this area it's peeling stick so I would peel away a 9 in piece or maybe a 12in piece and I would stick it right to the wall more on this tape later but let's get into flashing what it is and how it works so usually flashing is made of steel or aluminum and it comes bent in a in a profile this is called inch and a half Z metal flashing so inch and a half means it's an inch and a half this way from the point that it drips over to the point it goes up on this particular piece it has a 2in rise this side goes up against the wall and then it has about a/ in to H 38 to a/ inch lip that hangs over so here's your ledger board here's your wall now depending on how this is trimmed you may have siding on the wall sometimes depending on the type of deck we're building we'll peel this back up to a certain height or if it's feasible if it's lap siding or something bevel then we'll loosen that piece of bevel we'll clear all the nails up underneath the bevel so that we can slide this 2-in piece of flashing up and into position now it's always easier to do this before the joists are installed on the deck so even if you have to pre-install the flashing and get it up out of the way or something like that go ahead and do that but always install your flashing before you install your joist it just makes it a lot easier trust me I've done it always all different ways there's many ways to do this you just want to make sure you're doing it okay so on a standard deck build we'll we'll either use this type of flashing Z metal so that once your siding comes down you have your deckboard that sits like this and you still have an inch or so of metal that goes up the wall and then your siding detail will come down and cover that up so any weather that comes in it has to hit that and then it'll hit this piece of flashing and then it will drain all way and down so it's not going behind the ledger board which is really bad for the house but at least we have that protective layer of G tape behind this in case water does get back there somehow this is going to help protect the house and take the moisture Down and Out versus down the wall and into the interior of the home that's probably our tried and true method but before we finish if you're going to have any Fasteners going through this metal you just created a leak so just to be able to protect that potential I usually take waterproof membrane tape like so and I'm going to go in and at least I'm going to tape the top Edge like this and you could use 2 in for this I'm going to I'm going to tape the top of this so that any Fastener I put through this is going to be sealed up before it hits the metal the screw is going to be self-sealing so that moisture won't go through this and then potentially get behind this and into the wall of the house I can't tell you how many times we've done demos after demo we find so much rot and Decay because people don't flash The Ledger to the house it could have been a weekend warrior that built a previous deck an older contractor ah we don't need it whatever like I said before one of the cheapest methods to keep the moisture out of the wall of the house okay and in certain circumstances we've also just used waterproof membrane tape as are flashing where we just came in and we might use a piece of 6 in so we can come up the wall and then on top of the joist and then roll it over the top of the Ledger like that that's basically doing the same thing and once the first board's installed you're not going to have any wear and tear on that piece so I like to do a combination of both because I just I'm a professional and and I'm overachiever so uh but I've also done this both ways I've done it singularly with g-tape and I've done it also with just the metal because I didn't have any Fasteners going through the metal okay but again this is a great way to add extra insurance to your deck project to make sure that that doesn't leak and again can't stress enough guys how important this step is when you're building your deck okay so in the past maybe I've needed to go up the wall higher than 2 in because of that sometimes I'll use a 3in by 2in profile this is a galvanized metal flashing and what I've done I you could use this two different ways you can go up the wall three inches that way you have two inches of metal above your decking and it' be really hard and then you could also tape this if if you have the availability to take a layer of your siding off then you can even tape this like this over the top of your flashing and you can go up as high as you want really just again another layer we're going to nail this every 2 to four feet to keep it in place but once the decking is installed this really isn't going to go anywhere uh depending on if there's any Fasteners again going into the metal if you're going to have Fasteners in the metal I recommend that you put some waterproof membrane tape on it it sticks really well to galvanized and metal flashing like so so when you add those screws you're not creating a and again if you needed if you wanted to get the moisture maybe have a spot that really gets wet you may consider doing a 3X3 or having the 3-in lip hang out that far so the water has a drip line that's about an inch and a half away from The Ledger it's another viable option if you need that additional drip edge or whatever I doubt it's going to curl back that far I've done this before as well just in certain circumstances just depending on what you have for your eaves or your home if there's no Eaves and it gets a lot of weather you know you're going to want to protect that as much as you possibly can and then here's one other product that we have that we use all the time for our waterproof bladder system this is EPDM pond liner and whenever we're doing a waterproof deck we like to run the EPDM 6 in up the wall every time we do a waterproof bladder on a deck we're pulling six in of material off the side of the house and we're running every single bladder piece 6 in up the wall so any water that ever gets up in here has to find a path back into the bladder and work its way out to the outside of the deck lately we've been doing a lot of bladder so we've been ripping a lot of siding off the sides of houses and then doing uh retrims and actually I think we'll shoot a separate video on that when the time is right about how to trim out a waterproof bladder what we started with and how we finished it but the whole idea here is that we're getting this up the wall enough to where I don't care what kind of monsoon comes in the water is not getting past this and this also qualifies as flashing and again usually we're taping the seams of all this stuff so we run the joist tape wherever there's a seam right here and that's where the the screw would go from fastening the decking so that's covered as well there you go guys you can pick this product up at your local lumber yard sometimes I get at Home Depot when I'm in a pinch and they have flashing in one of the aisles there in the building material section you know just pick up some inch and a half ZM metal make sure it's inch and a half cuz they sell everything from like 3/8 half in Z 3/4 1 inch the thing that's got me before I've even had yard guys give me inch and a quarter instead of inch and a half and then inch and a quarter doesn't fit on your Ledger like it's supposed to so then you have an issue you got to take all that back and get inch and a half and that's frustrating when you're ready to build and you're ready to put the flashing in and you can't because it it doesn't reach the shoulder of this board and it's short that's super frustrating just make sure you got that inch and a half Z metal if you have an inch and a half Ledger now if your Ledger happens to be thinner than that then uh you'll have to get the cording size flashing for that it seems like a very simple step it could save you potentially thousands of repair dollars in the future so don't forget to put the flashing on your deck you know how to do it now so go out and don't forget click that subscribe button hit that Bell icon to be notified when we're putting out new content thanks for watching this video don't forget to leave me a comment below and leave me your flashing stories and uh really appreciate you coming to our Channel and taking a look thanks for watching guys have a great day

Channel: drdecks

Views: 33,110

Keywords: Dr decks, drdecks, deck building, custom decks, pacific northwest, carpentry, decks, deck, deck board bending, deck framing, deck stairs, deck blocking, martinez hammer, under deck waterproofing, diy, how to, building, construction, tools, do it yourself, build deck, outdoor living, outdoor deck

Id: 5R3RPFcQDS4

Length: 9min 45sec (585 seconds)

Published: Tue Nov 14 2023