Leaking windows help
Awhile back I posted with some help on flashing and siding strategy for my tiny house project. This project has minimal eaves, with reclaimed cedar windows. We are in a tropical area, very wet.
Anyway after ordering a bunch of flashing a working pretty hard over the past weeks, this morning after a heavy rain, I noticed most of the windows leaking. I expected some to leak but was pretty disheartened when even the window I partially j trimmed was leaking. Got me questioning where this strategy is going and if I need to be looking to other options as well. Since it’s a tiny house on wheels I have width restrictions, any eaves or awnings would have to be removable or foldable. One idea was to extend the roof with corrugated cuts and just take the cuts off when I plan to move. I’ve seen other plans of removals type awnings, but I do have a lot of windows and that seems like a lot of awnings to build Hoping that maybe someone can give me some ideas to keep this project doing in the dry direction. Maybe I just messed up the trim? I attached pictures for a closer look. The windows are timber framed so no flange. I used flashing tape to make a flange and used Vulkam silicone to back bed the j trim in. One thing is that the tape has been exposed for a couple months to UV. Could be a fail point I guess. It’s a little hard to get a tight fit with the window frame and j trim because the edges of some of the windows are not exactly flat. Some seem like they will fit tighter though. I could also try re taping the windows in a way that allows the trim to sit better. Anyway I’m open to suggestions and help. Been a bit of a battle. Thanks!
i did add the gutter yesterday and that seemed to decrease water getting in the windows someone also mentioned sanding the window sill to achieve a slope so water doesn’t sit on them
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You'll have to spend some time trying to find out where the leaks are. Have someone slowly go over the window perimeter with a garden hose while you observe from inside. The leaks may be in the window units themselves, not between the window frame and the rough opening.
Did you flash the rough openings before installing the windows? With a sloped rough sill or a back dam, the water should drain back to the exterior. Just make sure you don't tape or caulk the gap at the bottom of the windows or you will trap the water on the sill. Tape or caulk on the interior for air tightness.
Hey Frank thanks for the response,
As I am checking into it there could be a couple places where could come in since they are timber have some have tiny nail holes ( I did silicone them)
As for flashing yes I tape flashed the openings. A combination of stretch tape and protecto wrap. Did the sills, house wrap wrapped around the sides, drip edge under house wrap and tyvek taped to re seal on the top of window. As I said the windows have to flange so I then had to create one around the window with 6 inch flashing tape. https://m.youtube.com/watch?v=QDLLgV2fgx4 There’s a YouTube link on how I did my windows. Starts at 51min 42 sec.
The thing I didn’t do, but brought up with the builder I was working with, who didn’t deem it necessary was the sloped window wedge on the sill. My rough openings do not have a slope on the framing itself. Maybe I could install something there after the fact? I do have 1/2 inch gap still in the RO so maybe that is enough space to insert something that would help shed water to exterior? I will attach some photos of the RO.
Here you can see the flashing tape making a flange. There is a bit of light there, because the tape sometimes can’t seal perfectly to the uneven surface of the wood. But I also have metal trim and silicone on the exterior.
^^
Since these are reclaimed windows, I was thinking more about worn-out or sun-damaged gaskets and glazing seals/beads. You might need to get a glazier to come out and recondition them if that wasn't done already.
The face-sealed approach to window installation seems risky in your rainy climate and with minimal overhangs. But if you're going to tape the bottom edge then be sure to use a vapor-permeable tape so water can slowly dry out. Leaving a drainage gap would be more robust. I've never used flangeless windows myself but thinking about it, I might tape a flap of crinkled housewrap (ex. Tyvek Drainwrap) to the bottom of the window to shield the gap from wind-blown water, but leave the bottom edge of the housewrap mostly open for drainage.
Thanks Frank.
Yeah they could use a little work. Iooking like I will try and figure out some temporary awning design to not have them get so much exposure to begin with. The the wind driven rain will still be an issue.
Do you have any references for water permeable flashing tape? Also any reference to what you are meaning with the tyvek flap? Trying to visualize.
Any knowledge of a way to put in a sill wedge after the window has been placed? I still have a half inch gap under there to work with.
Thanks again.
Draw a section of how you waterproofed, it is very hard to tell anything from photos.