fiberglass windows

Healthy Homes & Home Performance - Windows

Check out this video to learn what to look for when selecting new windows for your home.

For the PNW climate, we recommend a U-Value of 0.25 or less and SHGC of around 0.25. Fiberglass frames are our favorite as they are the most stable over time and won’t warp like vinyl. Plus, they are paintable if you ever want to change the color without replacing!

Window Install

My new fiberglass windows from Milgard had been ready for me to pick up since May 23rd, but I was not ready for them until after this past weekend of Prosoco R-Guard application. On Wednesday, I excitedly drove to the Milgard manufacturing plant in Tualatin to pick them up. Luckily all five fit in my Subaru!
I was impressed by the amount of packaging they had, although I had called the day before to ensure they would be ready and inquired about packaging needs so maybe they added more for me. I did check them over while we installed them to ensure that they were in good condition and they all were so I should be good to go. Milgard has a lifetime warranty on their windows which will be great if I have any problems with them.
My friend, Nicole, who I met though the AmeriCorps program working for Habitat for Humanity, took time out of her evening to venture out to site to help me get them all installed so I wouldn't have to worry about them being stored on site. I was very grateful to have her experienced help and agility on ladders to carefully hand up the windows, shim them and temporarily screw them into place. All five windows took about 2 1/2 hours to install and then it was burrito time!
My friend Anne, came out on Friday to install the backer rod around the windows on the inside. We realized that although the gap around the window was only 1/8", we needed more than 3/8" backer rod to fill the gap since it was deeper behind. I ran to the local ACE store for some 1/2" and 5/8" backer rod while Anne used up the 3/8" I had bought from Parr Lumber.
When I returned, we continued to install several layers of backer rod so that we would use less of the caulk. Finally, we caulked around all of the window edges with the Prosoco AirDam product. This product could have also been used behind the window flanges as they were installed but Tom said that was overkill and it would have been messy so I chose not to. I did install more Fast Flash over the top and side flanges after removing the screws although it was also not necessary. I think it's a good method to have some redundancy in building though. More photos can be found on my flickr!

Windows: The Eyes and More


Windows serve several purposes in homes. They provide views outside and inside, let natural light brighten a space, enable ventilation if operable and allow for passive solar heating. The materials and craftsmanship of windows influence the character of the home. Homes built in the early 1900's usually had wood framed windows with single pane glass. In the middle of the century, aluminum windows became popular. Then vinyl was introduced as a lower cost option. Now fiberglass framed double or triple pane windows with special coatings and gas fillings are the most energy efficient windows made. 

Since I have a background in energy efficiency, I decided to go with fiberglass windows for my tiny house. I chose Milgard because they have a local manufacturing plant, are based on the west coast, and have awesome customer service from what I have heard. Milgard makes all different types of windows including wood, aluminum, vinyl and fiberglass all with new technology like SunCoatMAX for improved energy efficiency. I looked into the Essence Series which is a fiberglass clad wood window so you have the warm feeling of wood inside and the durability of fiberglass on the outside. Ultimately, I decided that if I wanted wood windows, I would also want to upgrade the hardware from standard white or clay handles to satin nickel or oil-rubbed bronze for aesthetics. However, the cost of doing so was around $200 per handle! I also thought about the WoodClad series to have that natural wood feel inside from the veneer but have a more durable mainly fiberglass framed window. When I saw the window in person, I did not really like the veneer finish compared to the solid wood of the Essence Series. I finally chose the Ultra Series which is an all fiberglass framed window for its strength and durability.

The Ultra Series fiberglass windows are great since they are made of glass fibers, they expand and contract at the same rate as the glass they frame. This means lower stress on seals and greater durability which I think makes them ideal for tiny homes that are mobile. Milgard is also the only window company that offers a full lifetime warranty for parts, labor and glass breakage for this window series. (Other companies offer a limited warranty of 20 years for glass seals and 10 years for manufacturing defects.) I can see how considering this type of warranty could seem excessive depending on how long you plan to live in the home and you may find that salvaging windows is a more cost effective solution. However, new windows that are more energy efficient will reduce heating and cooling bills over time as well as provide more thermal comfort inside. Higher upfront cost products with low operating costs can actually be less expensive over the long term which is something to consider.

Cost, aesthetics and energy efficiency are also considerations when deciding on the type of operating style. Picture windows are the least expensive since they have no moving parts and are also most energy efficient since they are fixed (but do not allow for ventilation). Slider windows are the least expensive operable window, then single hung, double hung, casement and awning. Awning windows are most expensive due to their moving parts, but they are the most energy efficient of the operable windows and can be left open in the rain without too much concern of rain being driven inside. I decided to go with all awning windows, three 24"x30" RO (rough opening) and two 48"x18" RO since I plan to do a 24" OC wall system. I opted for the standard clay colored hardware with a white frame which I plan to paint (another benefit of fiberglass over vinyl). You can choose one of Milgard's color options but again, that will add on about another $100 per window. Since I do not have money in my budget for that and am unsure of what color I want the frames, I just decided to order white. In the end, I paid almost $2,000 for 5 new windows or about $400 each.

Diana from Windows Only was awesome to work with in answering my questions and getting my windows ordered. She is really into tiny homes, travel trailers and is considering building a tiny house herself! I did do price comparison quotes with other companies and found that the cost per window only varied about $30 from the low end to high end of the spectrum. Customer service was really the deciding factor of who I chose to order from and no one came close to helping me as much as Diana did. I highly recommend her and Windows Only!