German flangeless window install and flashing details
casegreenbob
| Posted in Green Building Techniques on
I have an upcoming job with German tilt turn windows, they don’t come with flanges like US windows typically do. My install plan is to screw through the frame (unless someone has a better idea) and once installed I am not that concerned about getting them air sealed. What I am trying to figure out is what is the best way to integrate them with the WRB and make sure they are not going to allow water into the home? Anybody know of a manufacturer who publishes good instructions for this? Maybe a German site that shows the materials and steps? This particular manufacturer does not.
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Replies
Bob,
Check out Zola (http://www.zolawindows.com) and Intus (http://www.intuswindows.com). They both have installation instructions/diagrams on their website. Much of it depends on your wall system and the location of the windows in the wall. I purchased European tilt/turn windows for my house and installed most of them using GRK screws through the frame. I did use the clips on my two fixed windows and they work better than I assumed. Both methods work well.
Bob- are you buying the windows directly from the manufacturer? If from a US distributor, you might check with them to see if they have any instructions. They might be able to steer you to another contractor who has installed them.
Our Intus windows came with heavy steel clips that snap into the frame and then the clips get attached to the rough opening. Our dealer, Performance Building Supply in Portland ME, came out and spent several hours with our contractor showing how to install and air seal them. It was very helpful, much better than a video or printed instructions. I'd be a bit concerned about screwing through the window frames unless I had the OK from the manufacturer.
Our windows were placed roughly in the middle of our double stud wall.
Stephen, Intus gives instructions for clip or screw installation: http://intuswindows.com/wp-content/uploads/2013/03/Window-installation-with-screws-and_or-brackets-05-17-2013.pdf
The screws allow for easier air sealing on the interior side of the window. Clips are necessary for fixed units and are surprisingly strong. I installed more screws and clips than was recommended on my windows, just to be on the safe side.
Adam- we used clips for both fixed and tilt-turn windows. Once our contractor did a few, he found it a pretty simple and sturdy system. Those windows sure are heavy, though.
Adam, thanks for the lead on zolawindows.com, I hadn't spotted that one yet. Intus does a great job of showing the install but I haven't yet found any details on their site for keeping out water. If anyone knows of more details for keeping out water let me know.
We are buying windows straight from the manufacturer and they do not have any details that apply to US construction schemes so that is why I am trying to find all the info I can. Thanks for everyones input and again I would say the install is not something I am worried about. Screwing through the frame or using the clips both look easy and secure. Water management details are what I can't find info on so if anyone knows of more details on this let me know.
Bob-Here's a photo of one of our windows that might help. Basically, we taped around the outside of the opening, foamed the space between the rough opening and the window and then taped the inside.
Bob, how did you end up installing your German windows? I have the same problem. It’s really hard to find info on the www about this kind of installation. Did you take photos during your install? How did you do the flashing, how the outside casing? The more information and insight you are willing to give, the better! Thank you.
Possibly useful: https://foursevenfive.com/blog/how-to-prepare-for-high-performance-windows/ and https://foursevenfive.com/blog/ideal-window-installation-improving-best-practices/
Bob,
We went with German windows, too. I write about the install process on our blog here:
https://kimchiandkraut.net/2018/11/12/windows-and-doors-air-sealing-8/
I link to some Hammer and Hand videos in the body of the blog post that were a big help to me when figuring out installation details.
Instead of using canned foam for air sealing around the window and door frames we used black expanding foam tape on a roll and were very happy with its performance (available from Small Planet Supply or 475 HPBS). More expensive than the canned foam, but hard to beat. We also used Profil tape (from 475HPBS) to connect the window buck- black foam - window frame in a "belt and suspenders" approach to keep out air and water.
Oops, just realized this is an older question. Hope this helps you, Pellepam!
Hi,
I'm in a similar situation. The homeowner is buying windows straight from the manufacturer and they do not have any details that apply to North America construction. Water management details are what I can't find info on so if anyone knows of more details on this let me know.
Thank you.
Jake Bruton posted about making these kind of windows weathertight last week:
https://www.greenbuildingadvisor.com/article/installing-flangeless-windows
I also have a lot of photos and link to how-to videos from others here:
https://kimchiandkraut.net/2018/11/12/windows-and-doors-air-sealing-8/
I found the Hammer and Hand series of videos on installing these kind of windows to be the most helpful.
I, too, am going to use tilt/turn windows in my new construction. Rather than using tape, I plan to use Prosoco fluid applied material to flash the RO. Matt Risinger(Build Show) and Hammer and Hand have videos detailing fluid applied application.
edited to add: The window install will follow Jake Bruton's method, but using fluid applied rather than tape.
In my construction, I plan to build picture frame trim with exterior insulation. Risinger has a video showing that trim although used with a flanged window here:
https://www.youtube.com/watch?v=yT-abBfhRaQ
My question is how to install metal head flashing with that trim. My guess is to put a piece of insulation behind the trim that is the same width, nail the head flashing to the sheathing and seal it with fluid applied. So it will run from the WRB out over the piece of insulation and the top of the trim. Any comments on a better way?