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KatieAK 03-31-2010 04:23 PM

How to 'finish' outside of replacement window?
6 Attachment(s)

I need help -- long story, but the 'hired (family) help' we had replacing our kitchen window had to leave mid-project, and we're stuck trying to finish it up on our own. Problem is, we know nothing about finishing exterior trim/flashing/siding, except for the little I've tried to read now online. I'm hoping we can get some guidance from you knowledgeable folks, to give us an idea if we can handle this as 'newbies', or if we really should hire it out. Here is goes:

Current situation: the new, awning-style vinyl window is fixed in place (we think), to the point of being foamed in from the inside. However, on the outside, the j-channel and brick mould are not cut/in place, and I'm not sure how to proceed on making sure it's water sealed properly -- that's what we need advice on.

I have attached the as-is pictures -- hopefully those will help make sense of my descriptions/questions below.

The house is a 1969 home in Anchorage, AK with aluminum siding, with no building wrap underneath (just thick buffalo board). There is a good overhang above the window (~2 ft.?), so the window doesn't get a lot of direct exposure. When removing the old window there were no evident signs of water leakage/rot.

The new window does have a nailing fin, although it is not actually mechanically-fastened in place -- the installer used DAP 3.0 caulk/adhesive (for the cold-weather application -- it's the black stuff shown in the photos, as I think he got the roofing type by mistake!?). He did create a sort of 'sill plate' with Protecto-wrap tape, but as far as I can tell, it's not taped/flashed anywhere else along the perimeter.

Here are my questions:

- Should we also mechanically fasten the window to the house sheathing, as extra security (since we have the fin there), or should the caulk/adhesive that's already been used enough?

- Can we proceed with installing J-channel/brick mould without adding more Protecto-wrap or flashing along the perimeter of the window? If not, what could/should we do, trying to both minimize the disruption to the siding, and do an adequate job of protecting against water? [I've read that in an ideal situation, we'd have house wrap, and then would layer Protecto-wrap over that... but seeing that we don't have house wrap and aren't going to redo siding anytime soon to add it underneath, what should we do? I also have read some advice against J-channel altogether, but I have no idea how to do other flashing in our application -- any suggestions to that end?]

- Assuming we do use J-channel, can it be used on all 4 sides of the window (including underneath), or do we need to use the specific under-sill type of siding piece for the bottom? (We have J-channel and metal roll flashing on site, but not the specific under-sill type piece - so it'd be nice to make use of what we have here, if it's not a big deal to substitute.)

- In the second to last picture I attached, I show the bottom corner of another window on the house, showing how the J-channel ends and the under-sill piece extends further out to the side -- is this the correct configuration (if I do indeed go buy that special under-sill piece)?

- In the final pictured attached, I show the top corner of the replaced window, showing the old J-channel and how it was configured - it appears they cut/placed the top horizontal channel so that it sticks out straight to the side, further out than the window unit. Should we try to configure our new J-channel installation the same way? I've read something about trying to get the top channel piece to bend down after extending out beyond the unit... is this better, and if so, how do we achieve that?

- One more question - what do we do with the big 'fin' that curls up from the siding underneath the window? I guess that will depend on what we use down there... but if you could address that too in your suggestions/explanation, that would be great!

Hope this isn't too many questions -- but thanks in advance for any help you can give. I'm hoping we can finish this on our own, as we're already over-budget... but will humbly accept advice to hire a professional, if it's not something to attempt as a first-timer! :)

detailedEye 04-01-2010 02:50 PM

If it were me I would definitely want more than DAP sealant holding my window inplace. It should be nailed with 1 1/2" galvanized roofing nails every 6"-8".

KatieAK 04-01-2010 03:48 PM

Thanks, Detailedeye - that's what I figured; best to add fasteners. Any feedback/ideas for the rest of the project (more wrap/flashing or not, and what/how to use to interface siding and direct water)? I'm from MN by the way -- wish we were as far along into spring up here as you guys are down there....

detailedEye 04-01-2010 04:58 PM

Sorry, I've never worked with J channel. I'm sure someone will chime in. You might check out YouTube, there are some pretty good window install videos out there...some not so good too.

Yes, it's been almost 70 here the last 2 days. The first March in over 130 years we haven't had any snow! Very Nice!!

kwikfishron 04-01-2010 05:35 PM

199 Attachment(s)
Nice mess you got there.

Now that your siding is to short you’re going to have to trim the window. You have two choices, either rip custom with trim to fit between the window and the J which would look fine if they didn’t chop off the bottom of the J, or you can get rid of the J and just trim up to the siding and caulk. Be sure to install some Z metal flashing above the top piece of trim. Either way use 2x trim so you stand proud of the window and the siding so you have a nice caulk joint.

If you choose to get rig of the J you should pull the window so you can sawzal the J nails to get it out without damaging the siding.

KatieAK 04-01-2010 06:57 PM

Quickfishron - actually, we do have trim/brickmould already ripped to width to fit in that gap (not yet mitered/cut, but I think we can figure that out).

Our problem is not knowing what, if anything, we can put on the sheathing surface to protect against water -- currently it looks like there is perhaps felt paper (now compromised in some placed - with a few visible rips) nailed over the buffalo board on the top and sides of the window, but nothing at all under the window (just buffalo board). We don't want to have to pull the siding, so are trying to figure out if there's something we can do with the space/constraints we have... like putting flashing/Protecto-wrap tape along the top and sides, maybe trying to tuck it behind the siding as best we can?

As for the J-channel/siding situation, yes, it's a mess. We actually need to replace the J-channel on the sides, as the current stuff is too short (the new window is a few inches taller than the old one), and the right side piece is damaged at the top. How can we remove the side J-channel with least disruption to the siding (and window - can't imagine pulling it out at this point)? Any way to gently pry the nails loose enough to get a blade back in there w/out removing the window? But then, how would we nail the new J-channel in, even if we did get the old out w/out removing siding? Argh - not seeing a good solution here. Ideas??

Thanks much for the help.

kwikfishron 04-01-2010 07:21 PM

199 Attachment(s)
You do have enough room to replace the J without removing the siding, if you can get the old stuff out you can install new J. You can’t nail the new J but it doesn't need it, between it being sandwiched under the siding and against the window and caulked in where is it going to go? It’s tricky at best but can be done.

KatieAK 04-01-2010 07:30 PM

OK, Quickfishron, so there might be hope on getting out the old J-channel? Maybe we could get a grinder in there (I've never used it, though we recently got one), to cut the nails of the old J? Problem is, the window does stick out beyond the siding plane, which means it's in the way. Hmm, we'll be working on this this weekend, so maybe we'll have to experiment (any suggestions/tips would be great!).

Want to clarify on what you wrote about the new J-channel. IF we can get the old out leaving the siding as-is, then are you suggesting that we could use caulk/adhesive to affix it, rather than nails? (That'd be great!) If so, what caulk to use? We'd be placing it between the J-channel and the buffalo board, right?

Thanks again!

detailedEye 04-01-2010 08:38 PM

You might be able to get a small hand held hacksaw in between to cut the nails. A "utility hacksaw".

kwikfishron 04-02-2010 06:37 AM

199 Attachment(s)
I don’t know about the grinder, would hate to see that thing get away from you, a sawzal would be a better choice.
If your going to try to replace the J get it in vinyl not aluminum. The vinyl will bend some and would be easier to slip the flange behind the siding, the aluminum has no give to it and would be real tough to slip in without destroying it.

Once you get the J in and the window trimmed you’ll be able to caulk the trim to window and the trim to J. If your “no nail” J doesn’t lay flat you can throw a couple of baby nails or even small stainless screws through the side of the J into the trim.

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