I need some help (advice on windows)
I’m in the process of building a new house. I am zone 6, I have the house orientated with lots of glazing on the south side.Trying to gain as much heat from the sun as possible. But i don’t want to get cooked in the summer. I have external shading designed on that side. I have a R-20 under my slab, R-30 on my foundation walls, R-40 walls, and a R-60 cap. I am shooting for a .6 ACH at 50 pascals or less.
I know everything is a trade off, I’m researching windows I’ve done a bunch of reading on here. I like the Intus windows, but my question is, are there any manufacturers of tilt and turn windows that meet Passive house standards that come with exterior trim and a nailing flange already on them for ease of installation. Thank You
GBA Detail Library
A collection of one thousand construction details organized by climate and house part
Replies
Marvin windows have a line of Passive House type window products now and if they are like what I have installed in the past they come with nailing flanges if that is what you need.
Does Marvin have a tilt and turn? Also don't they have some kind of solar film in their glazing that may not be as efficient as some of the European of Canadian windows?
Hi Kirk, I recently did some research into Marvin windows and got a bid from them, but I didn't end up using them so I don't have any real world experience. However, I did see they produced a tilt and turn style window:
(http://www.marvin.com/windows/tilt-turn-hopper-windows/), although I don't know if it comes with a nailing flange. Also, Marvin uses a soft coat from Cardinal -- LOE 180 - that has a center of glass SHGC of 0.69 for a dual pane IGU. Marvin has quite a few windows in the Energy Star "Most Efficient 2013" list and some are close to the performance you will find in European Windows.
(http://www.energystar.gov/index.cfm?c=most_efficient.me_casement). The best I saw was U 0.16, 0.44 SHGC. I'm pretty sure most of the European manufacturers use a COG SHGC number, yet NFRC uses a whole window number that includes the frame. Hopefully this helps you on your research, good luck!
We narrowed our window search to Marvin (Integrity fiberglass), Intus, and Alpen based on cost, performance, availability, and local/regional dealer support. We ended up going with Alpen (the 525 series) based on those factors with the key points being performance (Alpen better than Marvin) and shorter lead time (Alpen shorter than Intus). The house is still under construction, but we are happy with our choice.
Intus looks great, but Alpen would be worth a look too:
http://www.alpenhpp.com/passive-house
Installing windows without nailing flanges is not that difficult. It's actually easier to install windows without flanges once you see and know how it's done. I don't think you should compromise on quality and performance just to have a nailing flange. Is your contractor behind this?
Your initial choice of going with Intus Windows was a wise choice. They are used in many Passive Houses and the windows get excellent air infiltration ratings of <0.03 cfm². They come in all types of SHGC ratings depending on your climate and goals. You can get a SHGC of 0.37 - 0.65 and everything in between. The triple pane uPVC windows are built like a tank and seal like a bank vault door. Plus you have a R-7 window instead of a R-2 double pane window. There is a reason why so many people on this forum have used the Intus uPVC triple pane windows for their high energy builds. They are a great performing window while staying on budget.
I really think you should rethink the nailing flange decision. Installing windows without flanges is done all the time and it's not that difficult to do. If your contractor doesn't like it, find another installer. You have a home in a Zone 6 climate and it's really well insulated, cutting corners on the windows will be a big mistake. Especially if you are trying to achieve passive solar or passive house standards. Give Intus a call and have them bid out the windows and you will be pleasantly surprised. I think you will really regret it later on if you went with a different manufacturer simply because they had window flanges.