Hi -
Need some advise how to recover from a screw-up. I bought a couple Replacement style vinyl windows for a bathroom remodel project - I bought replacement because I didn't want to deal with removing the existing siding, but when I started to remove the old windows, I had trouble with the casement hardware and decided to just remove the entire window and install them as if new construction. I completely forgot about the nail fins being flush with the exterior window edge as opposed to centered. Now I have a problem figuring out how to close back up the exterior. I thought about maybe taking some 2x4 and cutting it down into a 'L' shape so the thicker edge recesses into the gap and the thinner edge laps over the siding, but that seems to be a recipe for water incursion problems.

Any assistance greatly appreciated. Oh, I'd also like to know is there anyway to better handle casement window rigging or are casements just not "replaceable"?

Thanks
Brian

 

Not sure I understand. Replacement windows don't come with nail fins, but windows that replace the whole frame do. If you removed the whole fram, you must have removed some of the siding. Now you need to fill in the siding or install larger trim pieces on the outside to fill the gap: ie, if the old trim was a 1x4, install a 1x6, or 1x8 to fill the gap. Be sure to properly flash and weatherproof the nailing fin edges. You can expand the opening with 1x or 2x lumber so you have a proper surface for nailing the fin.

 

Hi Bill - thanks for your response. From my experience all vinyl windows have nail fins - at least all that I have ever used. Perhaps my mistake is assuming that the nail fin needs to go against the studs as opposed to against the siding. The fin being flush to the exterior edge seems to indicate replacement windows are designed to be nailed to the siding, but I have attached directly to the rough framing. So now I have a question how to proceed because my window edge is already recessed relative to the house's siding

 

Replacement windows have no nailing fin and are sized to fit into an existing window frame. "New" construction windows have a nailing fin and the fin nails to the outside of the house sheathing/framing, not to the siding. The fin is normally set back to allow the windows to sit outside the finished siding. If your window frame is sized correctly to fit your old frame opening, cut off the nailing fin, and set the new frame in a bed of caulk, on the inside of the outside stop molding. If it is not sized correctly, it would be a bit more difficult to advise without seeing specifics.

 

ok, well, I ordered these 2 windows as "replacement" and they came with fins. I noted that the nail fin is flush with the outside edge of the window, as opposed to the New Construction windows I had worked with in previous projects, so I had just assumed that was the difference between the two styles. At any rate, I believe I have failed to adequately describe my problem - so I'll take one more stab at it and hope you or anyone is still following along

The nail fins are basically flush with the exterior edge of the window, so that the siding does not have a window frame to come flush to, instead the outside edge of the window frame is inset/recessed relative to the siding.

With other new cons windows I have installed, the vinyl window box and siding are roughly flush with each other, so that all you have to do is fill in the gap you cut out to remove the old window and top with proper flashing and trim.

 

what you have is a flush fin window. it is not made to be installed the way that you have it, although that might end up being just fine. with a flush fin window you normally set it in from the outside and it goes in until it is stopped by your siding (run a big bead of caulk around the inside of the fin before pushing the window into place). this is convenient because you don't have to install an exterior trim, that's the purpose of that fin. you'll notice it doesn't have any holes in it like a normal new construction window fin, that's because it's going to be seen all the way around when you're all done. your screws are ran sideways into the window opening and then caulk it on the outside and do your finish work on the inside.

 

Aha - Thanks for the info, that makes sense. Another lesson learned...