Tricky (To me) window installation

[AmateurGarageMan]

Maybe this is an easily solved problem, but I'm at a loss and not really sure where to go from here. For reference, I live in the caribbean, where flanged windows and wood framing really aren't a thing.

I have a wall, framed with 2x4s. I have 3/4" plywood sheathing on the outside. Tar paper barrier (Since house wrap isn't a thing here either). I now need to install my new windows, and I'm not sure how best to waterproof the package.

I have flashing tape, and dupont flex tape for the sill. So waterproofing the opening is not a big deal. Where I'm struggling is the actual installation of the windows. I only have experience installing flanged windows with vinyl siding, so getting to the finished product wasn't difficult. Install the window, install siding up to the window. Done. But with this project, I have a 3 1/2" rough opening frame (plus the 3/4" sheathing), but my windows are ALSO 3 1/2" thick. So do I install the windows flush with the sheathing? Do I install them so they're sticking out past the sheathing so that they'll be flush with the siding once that's installed? Do I install them flush with the inside of the rough opening?

And then once installed into the RO, how do I waterproof that installation? The RO will be taped and water tight, but how do I waterproof from the window to the RO? Do I run flashing tape up onto the face of my windows? And if so, how do I finish that detail so that the flashing tape isn't exposed?

I have tried googling this, but I may not be using the right search terms. I'm not a total novice to building, I've just never had to deal with a flangeless window, so I'm not sure about all of the finer installation details.

 

[Wolley]

Install the window flush with the sheathing. Old style wood windows use the outside trim as the flange. You could trim it first if you want. Caulking and paint to seal it up. Or wrap with aluminum and j channel for vinyl.

 

[Bert_]

I've installed wood windows. Nail the casing to the window then nail the casing to the wall. Siding gets butted up to the casing

 

[AmateurGarageMan]

These are aluminum windows - Think like "European style". This wall gets a lot of rain so I want to make sure I take every effort possible to seal it. Sounds like I could install flush with outside of sheathing, then flashing tape it to the sheathing, then when trimming, attach trim to sheathing but have it covering an inch of the window or so (Enough to hide the flashing tape), then caulk between trim and window. Seems like that might be as good as I could get with this. Thoughts?

 

[Bert_]

Show a picture

 

[alwaysFlOoReD]

Whatever you decide, make sure that water can escape out the bottom if there is condensation inside the opening.

 

[signcrafter]

What type of siding are you putting on? Usually they get put on flush with sheathing. Spray foamed between window and framing and caulked at outside. Bed depends on what siding you are using.

 

[FredWanaker]

you are in a hurricane area with wind driven rain. Ask the building department what the code is.

 

[AmateurGarageMan]

What type of siding are you putting on? Usually they get put on flush with sheathing. Spray foamed between window and framing and caulked at outside. Bed depends on what siding you are using.

I'm trying to find a local distributor of Hardie siding but so far coming up short. It will either be that or the 4x8 wooden sheet siding.

 

[PCustoms]

I'm trying to find a local distributor of Hardie siding but so far coming up short. It will either be that or the 4x8 wooden sheet siding.

Where/why did you get those windows?

This looks like new construction, a standard window with a flange would have been 100% easier. Without being there to mock up a few ideas, I'd set them flush to the outside sheathing then overlap my trim (flashed and caulked underneath) to the frame.

On the inside you'll have to build some custom molding, as you'll have about a 1.25" (or more) gap when you drywall/panel the interior.

If your putting 4x8' panels as siding that just adds to the issue IMHO.

 

[AmateurGarageMan]

Where/why did you get those windows?

This looks like new construction, a standard window with a flange would have been 100% easier. Without being there to mock up a few ideas, I'd set them flush to the outside sheathing then overlap my trim (flashed and caulked underneath) to the frame.

On the inside you'll have to build some custom molding, as you'll have about a 1.25" (or more) gap when you drywall/panel the interior.

If your putting 4x8' panels as siding that just adds to the issue IMHO.

Flanged windows are LITERALLY not a thing here. I called around 20 custom window manufacturers. It simply is not a product here because 99% of new construction is block.

 

[PCustoms]

Flanged windows are LITERALLY not a thing here. I called around 20 custom window manufacturers. It simply is not a product here because 99% of new construction is block.

Where is "here"?

I was thinking that looked to be meant for some sort of commercial install, block would make sense.

How much of a gap is there around the window?

 

[AmateurGarageMan]

Where is "here"?

I was thinking that looked to be meant for some sort of commercial install, block would make sense.

How much of a gap is there around the window?

Caribbean island. All houses here are made of block. This is literally the only type of window you can buy.

The RO is 1" larger than the window in both width and height.

 

[PCustoms]

Caribbean island. All houses here are made of block. This is literally the only type of window you can buy.

So why did you stick build?

The RO is 1" larger than the window in both width and height.

I was thinking of you could get some thin waterproof material and box out the frame, then you could just caulk it in like originally designed. With only 1/2 per side and material availability issues not sure what you could do.

I think your best bet is to set it flush to the outside wall and foam/caulk/tape as a few have detailed above.

 

[AmateurGarageMan]

So why did you stick build?


I was thinking of you could get some thin waterproof material and box out the frame, then you could just caulk it in like originally designed. With only 1/2 per side and material availability issues not sure what you could do.

I think your best bet is to set it flush to the outside wall and foam/caulk/tape as a few have detailed above.

I stick built because it's a shop not a house and I saved a bundle of money doing it this way. Not like you can't build with wood here. It's just not super common. I have a 60 year old house on my property that's wood framed.

Also people DO install these types of windows in wood framing here. They just don't typically care about the waterproofing aspect. I could throw them in and not worry about too, it but I'm trying to do it as correctly as possible with what I have available.

 

[AmateurGarageMan]

So why did you stick build?


I was thinking of you could get some thin waterproof material and box out the frame, then you could just caulk it in like originally designed. With only 1/2 per side and material availability issues not sure what you could do.

I think your best bet is to set it flush to the outside wall and foam/caulk/tape as a few have detailed above.

That's an interesting idea. I could box out the frame using PVC board which is widely available in 1/2". I've got the room for it. Then i could keep the window fully within my RO, not flush with the sheathing, which protects it even more from rain.

 

[loganb]

What is the exterior going to be? Wood like shown in the above pictures or stucco or some other siding material?

 

[AmateurGarageMan]

What is the exterior going to be? Wood like shown in the above pictures or stucco or some other siding material?

I don't have a plan yet. I wanted Hardie siding but it's proving difficult to find. May end up being the 4x8 wood panels as shown in the above photo. Not stucco though.

 

[PoorUB]

I think you need to decide on the siding before you commit on the how to mount the window!