Ahhh...Nothing warms the soul more then the look and feel of fiberglas???

Try Marvin Integrity. They make all fiberglass or fiberglass exterior, wood interior. I do not know the price but they are built tough and worth a look, even if it is only to compare.

GOod luck!

Calbay03, thank you for your response. I do have the Marvin rep coming out this week, and I'll assume they will offer some comparative insight between themselves and Marvin. I just don't love getting advice from a sales rep.

I appreciate your helpful thoughts. Thanks!

Slightly confused by your comment about "...between themselves and Marvin".

Marvin Windows and Doors, also known as just Marvin, owns Marvin Integrity and Marvin Infinity. The difference here is Marvin sells all wood or aluminum-clad wood interior windows and doors. Marvin Integrity is fiberglass.

I also do not trust sales reps. We spent about 6 months educating ourselves about windows before taking the plunge 4 years ago.

Hope it all works out well for your purchase.

Calbay03, often enough I confuse myself!

What I meant to write was Milgard; that I assume Marvin (Integrity) will offer up some comments about Milgard.

I've been doing a great deal of research, but there are some things I just can't find information on. Possibly you would have additional input about welded/fused corners on the fiberglass windows. Is this a big consideration with fiberglass? I've read that it's important with regards to a vinly window. Marvin Integrity injects some sort of seal into their corners, Milgard uses screws, and Pella Impervia seems to weld/fuse.

Any thoughts?? Should I be that concerned?

1) I would recommend argon. It prevents convection when there is a substantial difference between inside/outside temp. Heat from inside home heats inner pane which causes air to rise, comes in contact with cold outer pane which causes air to cool and drop. creates a "tornado" effect which "convects" heat outside of your home. Argon prevents this.

You can't fuse fiberglass. In order to do so, you would have to heat it to the melting point, then press it together. They can do that with vinyl but not with fiberglass. so the corners are screwed/glued. It's not a problem.

I like Milgard's Ultra product. I'm a dealer and have been selling it for a long time (over 7 years). It works great and the warranty is outstanding.

Hi sberg,

My info is 4 years old so things may have changed for the better (I hope) since then. Other pro-posters like Oberon, guy-exterior-man, paintbrush (?) and skydawggy are sure to have better information.

In general, we learned then that use of screws in vinyl windows is undesirable. Weld and fuse is much better. We did not find out what Integrity used to connect the joints, sorry.

Having worked with fiberglass as a hobby while in college, I will say that one piece formed fiberglass is the best because there is no seam. The second best would be weld or some sort of chemical (heat?) bonding that completely fuses the joints leaving no seeams. Beyond these two, I am now out of date as to what is best in joining fiberglass material. Using regular old screws is a definite no, no. You can check the local marina (if you live close by a lake, river or ocean) and ask the service people what they use for boat joints. Fiberglass boat hull is very common. You can then call Marvin Integrity and see what they say. This also tests Integrity's phone service quality. :-)

We also learned that the more "air pockets" in the window frame, the better. This is true for fiberglass, aluminum or vinyl. There is a special trade name for air pockets but I forgot what it is. Basically, a frame that has 1 simple air pocket between the outside and the inside layer suffers from transmission of heat and lack of strength. It is like a simple empty box compared with the same box filled with a few honeycomb structures. The one with the honeycomb (more air pockets) will be significantly stiffer and stronger. Depending on how the honeycomb is set up, they also slow or significantly reduce heat transfer. So more air pockets generally translate to stronger window and of course, will cost more.

If you have a good Marvin shop, ask to see a cross section of the window. We saw one in our local Marvin shop and it really helped. We asked for same from two local Milgard shops but they had none so we relied on on-line drawings from Milgard.

We ended up with Marvin (not Marvin Integrity) because Marvin Integrity was fairly new at the time and did not have the color we wanted.

Sorry, not much help here as it is near the limit of our research. We wanted wood interior to stain and we wanted solid wood pieces so we did not look too deeply into vinyl or fiberglass.

I do appreciate everyone's very interesting and helpful information about fiberglass. I will follow up with your suggestions and can then make a better informed choice. I really appreciate your help you guys!

sberg2007: Have you come to a decision about your fiberglass windows and doors?