Is There A Better Way to Flash Prehung Exterior Doors?

[Jason Laws]

I don't think that I have really been overly happy with how I have flashed these kinds of doors and lets face it: There isn't much to work with in the first place. When I first started doing these doors, I just caulked, with Geocel behind the brick molding and then around it when the door was done. Now I use 3' Grace Ice & Snow Sheild (applied right to the sheathing and t he top piece under the housewrap),as well I also caulk with Geocel under the sill, and with flashing there, too. But, there must be a better way and I would very much like to do this better. There is so much talk about doing the windows better, which is great, but what about the important front door? The house that I am building now has made me revisit the issue again.

So. what does everyone else do?

So, I am really interested in reading what your first hand experience has been and what has worked.

Jason Laws
Plain In Maine
Amity, Maine

[Bill Robinson]

Re: Is There A Better Way to Flash Prehung Exterior Doors?

Rough cut video with Kermit Ruffins.

http://youtu.be/xIL_LDKkKVE

[S.Joisey]

Re: Is There A Better Way to Flash Prehung Exterior Doors?

Drip cap at the top taped to the sheathing, pan at the bottom. Lap everything properly.

3M flashing tape is my fav, by far, esp in cold weather.

https://www.youtube.com/watch?v=zHLgCT_E37Y

[Jason Laws]

Re: Is There A Better Way to Flash Prehung Exterior Doors?

Does the 3M tape work at 0 or below? With our winters being long and cold, I almost always have to use a heat gun. Glad you mentioned the drip cap - forgot about that one nor was I ever really taught to use one at first. Thanks!

Jason Laws
Plain In Maine
Amity, Maine

[TSJHD1]

Re: Is There A Better Way to Flash Prehung Exterior Doors?

I like what Bill did in the video, in theory. But another way to accomplish essentially the same thing, but a bit simpler, would be to just remove the brick moldings first.

Maybe they make a type/brand of P&S tape with the release tape split down the center, but if they do, I'm not aware of it, and I'd think it would be more expensive. Or, you could make that cut yourself..., I suppose, but I'd be real wary of cutting into the tape itself, even if just a tiny bit.

So that's my first concern.

Second, the brick molding on these types of doors (think: ThermaTru) typically need extra nails anyway, and many times the brickmold is loose! Ie, you can remove it pretty quickly and easily. After its off, pull the nails with a pair of nippers.

With the brickmolding off the door, you have the added benefit of sliding full-length shims behind the jambs. I hate having to cut my shims into 3rds or quarters, then having to choose the right pair, only to find they are too tight or loose, then try a different shim..., back and forth, etc. And, if the trimmer stud is slightly twisted, with the brickmold removed, you can see that much clearer, and choose to put 2 shims in from one direction, and 1 shim from the other, to account for the trimmer twist.

So, so far, I've added a step by removing the brickmold, but I think it's more than offset when shimming the door.

Next, I just apply the P&S from the wall onto the edge of the jamb, lapping the jamb just to the point where the brickmold will be installed. This way, the P&S is closer to the entry point of any moisture intrusion, and just easier to install.

And now that I think about it, the P&S in the vid is actually 2 pieces mated together, right? (Or some special type that I'm unaware...)

So..., you either create that P&S yourself, so its sticky on one side on one half, and sticky on the other side on the other half, or you buy it that way...?

I now remember seeing this method at a JLC Live show several years ago, and you had to do all this yourself to create the P&S to work like in the video. I thought it was a bunch of unnecessary work then, when compared to simply removing the brickmold, and having 2 pieces mated to each other actually adds a bit more thickness, which even though its not much, can fight you when trying to get the inside edge of the jamb to be exactly 1/2" beyond the framing, an important but often overlooked detail when installing doors and windows, but one that makes trimming the inside a bit more time consuming.

I didn't mean for this to be so long-winded, or a total dis of Bill's method (it wasn't him who I saw do it this way at JLC, btw), but as I was writing, I kept remembering the finer points of why I just can't get behind this method. And as I recall, the class at JLC where I saw this method for the first time, was about exterior flashing details, and I picked up some good info. But when it came to this method, I wasn't the only one shaking my head.

So..., door shimmed, cut shims, install screws into hinges, install P&S on outside, re-install brickmold, (which has the added benefit of allowing you to do a better job (glue and screw if desired) of joining the corner miters together too, another typical weak point of these doors, in my experience), install drip cap, fold down housewrap and tape to drip cap. I do that part the same way as Bill, so there's that... LOL

Tom

[larryh]

Re: Is There A Better Way to Flash Prehung Exterior Doors?

With doors, you can flash the jamb and head till the cows come home and it won't matter because doors leak at the weather stripping and bottom sweep. It's important to have a good door pan, and a way for it to weep the water it catches.

[Bill Robinson]

Re: Is There A Better Way to Flash Prehung Exterior Doors?

Thanks Tom, I think.

We used to do this by using split SAF and making an "opposite" sticky side.

The product I was using in the video is DuPont, VF.

It is made to have s sickly side opposite. I am guessing it is still available but most likely special order.

That is a bit of a shame since it is a good way to do it.

Come see me in Providence in a couple of weeks and I will do it again like you saw it a few years ago, the old way.

I am doing 3M and Tamlyn there.

What I did not show in the video was a sill pan, head flashing was not necessary there since the door was on/in a covered porch.

[larryh]

Re: Is There A Better Way to Flash Prehung Exterior Doors?

I've seen quite a few tradesmen treating adhesive flashings as if they were a waterproof membrane. IE: Reverse laps, and using it in flat locations as a waterproof barrier. It does not work that way. It's sticky, but that sticky edge is not even close to water'proof'..especially on wood. It's just tape.

When I have a door or window that has a wood jamb and brickmold and really needs to have a good waterproof install, I take off the brick mold and install my own "nail fin" (a 1 1/2" L metal that is screwed to the jamb in a bead of sealant). Then the door or window can be caulked and nailed into the opening and another layer of flashing put over the nail fin.

[Bill Robinson]

Re: Is There A Better Way to Flash Prehung Exterior Doors?

Is waterproof really the term you mean to use?

I would be cautious about that.

The codes use interchangeably weather and water resistant (resistive) barrier.

WRB


I am guessing that is what you mean and SAF can reasonably be used as such.

Even your applied mounting/nailing/index fin is subject to failure depending on the type of sealant and application.

You are a cali guy, do you remember the SK-10 that was, and still may be used in some locations, to "flash" doors to whatever was on the wall.

There are a lot of ways to do this, the main thing is to have some protocol that is consistent and has a reasonable chance to work, be effective.

I like the VF or site made VF-like way of flashing brick mold doors.

And brick mold/block frame windows.

And of course there are several ways to do brick mold/block frame windows as well.

We can work on that next

[larryh]

Re: Is There A Better Way to Flash Prehung Exterior Doors?

Is waterproof really the term you mean to use?

I would be cautious about that.

The codes use interchangeably weather and water resistant (resistive) barrier.

WRB


I am guessing that is what you mean and SAF can reasonably be used as such.

Even your applied mounting/nailing/index fin is subject to failure depending on the type of sealant and application.

You are a cali guy, do you remember the SK-10 that was, and still may be used in some locations, to "flash" doors to whatever was on the wall.

There are a lot of ways to do this, the main thing is to have some protocol that is consistent and has a reasonable chance to work, be effective.

I like the VF or site made VF-like way of flashing brick mold doors.

And brick mold/block frame windows.

And of course there are several ways to do brick mold/block frame windows as well.

We can work on that next

Whut?

Real world experience speaking here- What I'm saying (again) is many people have more faith in the stickiness of adhesive flashings than they should have. I see them treat it is if it is a membrane, and it is not.

That's all, I'm not knocking your method. It's better than some other options and I've used it myself (however, in exposed conditions, the applied nail fin allows me to sleep better). And that's the beauty of this profession, right? Such variety. It's a moving target.. and we occasionally get to use our heads as well as just putting fun stuff together.

[Bill Robinson]

Re: Is There A Better Way to Flash Prehung Exterior Doors?

I often wonder how "real workd experience" differentiates things.

Or more likely, what it means.

Is your real world experience more or less than anyone else?

As far as stickiness, it does depend on several things, material, primer, temperature, application technique and some other things I am not thinking of.

And ALL I am saying is that most any method not done correctly is likely to fail.

Whether it be VF, site made flashings, applied mounting flange, whatever.

Even to the point that E-2112-07 and many manufacturers promote the idea of wrapping the flashing onto the frame when the mounting flange is not integral (water tight) to the window frame.

It is good an applied nail fin works for you in getting a good nights sleep, many folks need Ambien.

[larryh]

Re: Is There A Better Way to Flash Prehung Exterior Doors?

I often wonder how "real workd experience" differentiates things.

Or more likely, what it means.

Is your real world experience more or less than anyone else?

As far as stickiness, it does depend on several things, material, primer, temperature, application technique and some other things I am not thinking of.

And ALL I am saying is that most any method not done correctly is likely to fail.

Whether it be VF, site made flashings, applied mounting flange, whatever.

Even to the point that E-2112-07 and many manufacturers promote the idea of wrapping the flashing onto the frame when the mounting flange is not integral (water tight) to the window frame.

It is good an applied nail fin works for you in getting a good nights sleep, many folks need Ambien.

Real world experience in this case means I'm on the job long enough to have seen the stuff fall off. I've seen roofers have to take their roofs apart to repair their leaking backwards overlaps. Many may never get the opportunity and have no clue, which is why I said something. Don't take it personal.

Wrapping the flashing into the opening should be standard procedure if there is no flange.. A sill pan is next to useless if you don't.

[larryh]

Re: Is There A Better Way to Flash Prehung Exterior Doors?

Is your real world experience more or less than anyone else?

of course.

[larryh]

Re: Is There A Better Way to Flash Prehung Exterior Doors?

As far as stickiness, it does depend on several things, material, primer, temperature, application technique and some other things I am not thinking of.

Never seen anyone use primer.
Is the primer invisible? Because I didn't really see it in your video either.

[Jason Laws]

Re: Is There A Better Way to Flash Prehung Exterior Doors?

Great info that I am reading! It is nice that others are still thinking about a better way for this and other things. too. I have much food for thought.

I would wonder how an add on flange would help that much. I have thought of that too, but what if the sealant fails like all the other sealant on the door? A welded on one from the factory would be nice.

It would be nice to see doors that were made to be easily sealed. It sure would help much. And so many doors don't have overhangs to protect them.

Anyway, keep the posts coming - great stuff!!

Jason Laws
Plain In Maine
Amity, Maine