window install
The window installation crew started today and I have some major concerns that I was hoping experienced users here could help me understand. The installers are not the commercial crew we paid for, but service crew for the distributing company, which was the first red flag. They installed the first window and I had to tell them to stop because of my concerns.
These are thermally broken aluminum windows. First, they did not install the sill pan, they said the top flange screws would not hit the header (the rough opening is exactly 1/2″ larger all around as in the instructions). Second, the nail fin is screwed right onto the outside wall – not shimmed out to allow for any type of drainage. Third, they said they fill the space under the window full with open cell foam – same concern. Fourth, the blocks they used underneath are small pieces of regular plywood – will this not rot in the moisture under the sill. Last, they said they will need to unglaze most of the windows as they are too large and heavy for them to install and there is no equipment that can help them(most windows are 6×8). Why destroy a perfect factory assembly???
Please help me understand what is going on here and if these concerns are valid. This is my family’s one and only home and we are striving to make it as perfect as possible, rather than cut corners that will cost us in the end. Thank you so much.
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Replies
Pictures would help, but most important questions are:
1. What do your rough openings look like and how are they flashed?
2. How are you planning on flashing the window to the RO?
> First, they did not install the sill pan
Sounds like they are not following plans or other governing spec. Not good.
> they said the top flange screws would not hit the header
Header might not be critical. but you probably want these screws into framing. (Not clear what they're screwing up here.)
> Second, the nail fin is screwed right onto the outside wall – not shimmed out to allow for any type of drainage.
Talking about the bottom fin? If everything else were perfect, this isn't a concern in and of itself. Water will still get out. But, it sounds like there are concerns about the sill pan/flashing.
> Fourth, the blocks they used underneath are small pieces of regular plywood – will this not rot in the moisture under the sill.
Again, depends on other factors. If there's positive drainage, likely there will never be any water here to rot the wood. If there's no pitch or negative pitch, it could be a minor problem over time.
To reiterate, most critical things are your RO and its flashing, plan for flashing the window to that RO, and your overall air sealing methodology for the windows.
Patrick,
Thank you for your response. I am using Delta Vent SA as the WRB and the window RO flashing was done precisely as per their specs: Delta FAS corners, Flashing tape along the sill, multi band sealing the WRB along seams, corners and inside edges. Delta flashing will be used along the outside nail fins.
They said if they used the sillpan, it must sit flush on the sill and the window must sit right in it and so then the window will be too low for the top flange to hit the rough opening frame.