Tips on Choosing Window Frames
The window ER number, or Energy Rating is based on the entire window package, which includes the glass envelope, sash, the seals, and the frame.
The higher the positive ER number, the better.
Your choice of window frames may seem to be cosmetic only; but, it’s not that simple. Window frame design and material significantly impacts condensation resistance and heat loss, and therefore, the ER of windows. If you live where the temperature gets below freezing, frame choice is very important. Frame material also impacts the ongoing maintenance of your home.
Wood Frames:
Since wood has good insulating characteristics, it’s the traditional material for window frames. However, wood windows are expensive and will rapidly deteriorate if not sealed by paint or some other material. Wood frames may be clad with vinyl or aluminum, making a durable window package; but they have additional considerations.
Aluminum Frames:
Aluminum frames are strong and low-maintenance, but expensive and highly heat conductive unless designed with
a thermal break. Aluminum may have a natural finish, or covered with UV protective coatings to ensure long-life and low-maintenance.
PVC Frames:
PVC (poly vinyl chloride) frames are less expensive, are low- maintenance, have excellent insulating properties, and can be ribbed or honeycombed for strength, then filled with foam for a higher insulation rating. PVC frames have an embedded pigment, most commonly white, but also available in other colors. PVC frames may become discolored and brittle over time; although it’s possible, with some difficulty, to paint over the original pigment. PVC is structurally weak and may require aluminum or steel inserts for larger windows. In most cases though, PVC is a good choice for residential window frames and sashes.
Fiberglass Frames:
A relatively new material for window frames is fiberglass (glass reinforced polyester). This material is stronger than PVC and has lower maintenance requirements than wood. As with PVC, the fiberglass can be honeycombed and filled with foam. It accepts the same coatings as aluminum and is generally considered superior to wood, aluminum, and PVC. As with PVC, fiberglass frames may be painted over.
Tips on Window Frames:
When choosing the exterior colors of your home, be sure to consider your window frame colors.
Never use abrasive cleansers to clean aluminum, PVC or fiberglass window frames and they will grow old gracefully.
Take the time to research your windows thoroughly.
Useful Resources:
