We have about 25 Andersen 200 tilt-wash windows installed in a new home in 2010. They have been pretty much trouble free except for the occasional wind driven leak. The leaks happened pretty much right away, but mainly on the east facing side of the house, and on the 2nd floor. The leak drips down between the interior trim and window frame. The windows are installed with a 2″ trim board on the exterior above and below, and shutters on the sides. Stucco goes right up to the left and right side. There is metal drip flashing above the trim. The builder came out and caulked between the exterior trim and upper section of the window, and that pretty much took care of the issue. One window started leaking again this fall. The caulk looked good, but I added some more just in case. It is still leaking. On a heavy wind driven rain, it could be quite a bit of water. Unfortunately, I haven’t caught it happening. I removed all interior trim to try to figure out where the water is coming in, and I can’t seem to figure it out. My main question, is shouldn’t the nailing flange and flashing over the nailing flanges prevent water from coming in on the outside of the window. I would expect some leaking between the sash and frame, but this is coming in from the exterior. Any help in understanding how the water is getting in is greatly appreciated.
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You can't caulk your way out of a window leak, especially on top of existing caulk. You need to get all the old caulk out, use backer rod then re-caulk with a polyurethane sealant. I'd guess that your windows were installed before we started using self-sealing flashing. If the windows have a nailing flange the best fix would be to remove the exterior trim and properly flash them with either a liquid flashing or a self-sealing product. There are no short cuts.
I have Andersen 200s (actually Narrolines) in my own house, installed in the late 80s. They haven't leaked once.
I sealed them with Tyvek tape over the flanges. Now I'd use Vycor. Caulk doesn't last forever, and has to be done perfectly to keep wind driven rain out.
BTW- by 2010, I was only installing the 400 series windows. They may cost more, but IMO, are a better product
Thanks for the replies. The windows are installed with tyvek tape over the flanges. I took detailed pictures when we were building, so I could reference these things. We were on the fence between the 200 and 400 series. We were told the main difference is the available sizes and finishes, and they perform the same.
My assumption is that the flange provided a seal around the edge of the window. I don't see how water is getting around the flange and leaking in from the top. Water is not coming in from the sashes. Whats got me concerned is we found some rot behind the stucco in one section. It appears to have come in through a hairline crack, but not sure. I've checked all exterior wall receptacles for any visible rot, smell of mold, and it looks like the windows aren't leaking into the wall. I'm having a stucco inspection done tomorrow to confirm if there is any moisture around the windows.
Thanks again for the replies.