Maintenance

For most buildings maintenance costs represent the highest percentage of long-term costs at 67% of the life cycle cost; energy costs are 16% and initial costs are 17%. Therefore, all possible window maintenance activities must be evaluated in choosing window materials. These are: washing the glass, cleaning the window coverings, replacing broken parts, re-finishing and repairing interior surfaces, replacing broken glass or failed insulating glass.

Specifying between-the-glass blinds and shades in wood or aluminum windows can reduce maintenance on window treatments because they are located between the panes of glass where they are protected from dust and damage. Windows with interior access for washing the exterior provide easier, faster cleaning, which also can reduce maintenance costs.

The cost of replacing broken parts is comparable for wood, aluminum, vinyl, and fiberglass windows unless the manufacturer that supplied the original windows is no longer in business. Then replacement parts such as double-hung balances and casement hinges and cranks are not available and the only option is to replace the entire window.

Choice of framing materials also affects maintenance. Wood does not need frequent refinishing if the initial finish is high quality.

When the interiors of wood windows are finished properly (three coats) the finish can last up to 25 years or more. Typically, stain and two coats of varnish last longer than paint. Additionally, the finish on a wood frame can easily be repaired to keep a neat, clean appearance or changed to match new interior needs.

As an exterior material, aluminum offers very low maintenance, however, any scratches or damage to the interior finish cannot be easily repaired. Because aluminum frames are not typically re-finished during the life of the windows, aluminum may offer a cost advantage.

Vinyl offers a low maintenance finish, but the material has low durability because of its sensitivity to temperature changes. Over the long-term, this can cause other maintenance problems related to air and water leakage and operation issues.

Fiberglass offers low maintenance and its scratch resistance is six times better than vinyl. A powder-coat paint finish on fiberglass is quite durable and easily withstands scratching and denting.

Outlook

The variety of available options for windows continues to grow and enhance possibilities for more durable, efficient systems to meet many design needs. The growth of the green building movement has increased awareness of using natural resources wisely and influenced product development. The commercial market is leading this trend and windows can play a significant role in saving energy during the life of the building. Decisions made now in the choice of window materials will affect not only the daily comfort of building occupants but also the resources used to operate and maintain the building.