Vinyl siding junction at windows' built in J channels

Arky217

I have decided to hang vinyl siding directly on the Zip panel sheathing as recommended by the Zip manufacturer.

The nailing fins of my vinyl windows are flashed directly to the Zip sheathing.
The windows have built in 'J' channels that are 3/4" wide and 5/8" deep.

I can't seem to visualize what would keep water, when it runs down the windows' built in vertical 'J' channels, from going behind the siding when it reaches the bottom corners of the windows.

Not that it should be too big of a deal since any water would then just drain down the membrane surface of the Zip panel, but I would prefer that all the water remain on the outside of the siding.

Is there any way to manipulate the siding at the bottom corners of the windows so that no water will divert behind the siding at this point?

Thanks,
Arky

Tom Struble

i can't think of a way with windows with a built in J channel,the top lock/nailfin on vinyl siding is also the drainage leg, you could use pieces of zip tape on courses just under the window to divert water directly on to the top lock...this is sort of a jury rig thing

i'd be more concerned that you have kick out diverters installed at any roof abutments


vinyl siding is very good with regards to water drainage

loneframer

Water will get behind the siding at the bottom of the J, you need to get it back out. This is how I do it. The flashing is actually behind the windows nailing flange as well. This will work with built in J also. You need to address the top nailing flange just as importantly, as any condensation behind the siding may find it's way behind that flange. Caulking the window flanges before installation is a start. Taping the flange with Zip tape is a second line of defense.

The biggest downside to the Zip system is the difficulty in flashing wall penetrations properly, IMO.

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Tom Struble

there is no J channel,the window flange is taped with zip tape,that method does and can not not apply without modifying the window flashing detail that Huber supplies...not sure i would do that

zip wall needs no special treatment around the window openings other than the specified taping details,let the product do what it's supposed to

loneframer

I don't like the idea of depending on a taped joint to resist water infiltration.

I've used the zip system on a roof, but not walls. I'm curious how that tape holds after 15-20 years behind siding.

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It's not that it took him an hour to make 100 bucks, it's that it didn't take you 10 hours to save 100 bucks.

kwikfishron

The bottom flange is not taped in the zip window install details so Lones flashing detail will work fine if you didn’t tape the windows until the siding is installed.

The warranty on the tape is only 15 years. It would seem to me that installing vinyl siding over zip could be a long term recipe for disaster.

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Arky217

I don't know about 15-20 years, but the Zip tape has held up well on both the roof and walls for 6 months. (Just now finished covering the roof). In fact, I had Zip tape across the peak and when I cut out for the ridge vent, the Zip tape was still tightly adhered to the roof panels. So, I think that it will hold up for as long as I need it to (I'm 66 ).

That said, I like your method, Longframer, and think that I will use a piece of aluminum flashing at the corners as in your pic.
I think that even a 6" wide piece at each corner would probably divert most of the water onto the outside of the next lower course of siding.
I'll just slip it under the bottom nailing fin and over the nailing flange of the next lower course, as in your pic.

As to the top window nailing fin, it's Zip tape flashed, but also it's about the level as the bottom of the facia board on the 2' overhang, so I don't think any water will ever get up there.

Thanks for the replies,
Arky

Tom Struble

what seals the top of the flashing?just the window flange?now maybe a skirt installed with the sill flashing tape over the top which is a [better detail]would be the way to go,but unless spelled out or approved by Huber i wouldn't recommend it.don't try to re engineer an engineered system imo

go to one of the zipwall seminars that many lumbers yards host,these wall panels are more plastic than wood,good? bad? idk but defiantly a product that needs careful attention to manu.recomendations


plus were talking vinyl siding here,like i said a product that drains well already


op really should be asking zipwall these questions

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loneframer

IMO, the flashing behind the bottom nailing flange is nothing more than an extension of the nailing flange. I see no downside to extending the flange to lap onto the siding hem. If not with metal, then with PVC coil. I don't mind allowing the zip system to deal with minor water intrusion, but channels are just that, channels, that channel water from the top of window to the sides of window and eventually behind the siding. The 6" tabs will do the same job, but I prefer going the full width, during window installation, then trim the flashing to the siding lock during siding installation.

The flashing does the same thing as a kick-out at the fascia line, gets the water away from the wall and back to daylight. Job 1 in my opinion, regardless of zip walls specs.

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kwikfishron

Who’s trying to reengineer anything? Huber shows no tape on the bottom flange. Why wouldn’t you flash under the flange and over the panel like in the Lone pic.

http://www.zipsystem.com/uploads/res...2011014950.pdf

And yes I agree vinyl siding drains very well and it also allows water in like no other product I know.

I have visions of years of water trickling down the wall starting from as high as the soffits encountering the top edge of all of the tape seams.

I can’t imagine the tape out lasting the intended life of the siding but that’s just my opinion.

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loneframer

Interesting how their flanged window instructions provide a zip tape pan under the window unit. That's there to protect the framing from moisture.

If that is the case, why wouldn't you install the metal flashing before the pan, thereby diverting any water caught by the sill pan to the outside of the siding?

This is especially important on homes with windows on the second floor that stack over windows or doors on the first floor.

IMO, that tape will fail at some point in time, be it 5 years or 25 years. I vote for an insurance plan.

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It's not that it took him an hour to make 100 bucks, it's that it didn't take you 10 hours to save 100 bucks.

woodworkbykirk

i dont tape i use vycor or bluskin... im not sure what "ziptape" is, is it the same as tuck tape? if so in alberta tuck tape was banned by the alberta siding association a few years ago for the main reason that it was being used incorrectly by too many installers not to mention the glue fails after 2 years in a sub zero environment

kwikfishron

We're talking about the "Zip System" Kirk. http://huberwood.com/main.aspx?pagen...emwalloverview

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woodworkbykirk

ahh ok, i know what it is now. ive seen it in finehomebuilding magazine. this is a product that isnt available here yet. at the rate we get things it will be another 5 years or so... it only took nearly 2 years to get the latest paslode impulse framing gun in stores... i feel a certain picture of a collection coming on ... hey riz

MJW

Does this product breathe like Tyvek or felt is supposed to? Or is it similar to OSB in sealing up the wall cavity?


We flash like Loneframer, but I wear a shirt and don't wear a necklace.