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Personal: Residential


Fenestration Products –
Door Components and Types

Doors come in a wide variety of styles and options. Entry doors have one or two insulated door “slabs” that swing open. They may also have a window insert (that can be opened or that is fixed), one or two sidelights, or a transom. Patio doors almost always have a large glazed area. Most slide open, but other types (such as French, garden or terrace doors) swing open. Garden and terrace doors may also have a sidelight that opens. Another type, the tilt-turn door, swings open to provide an exit or tilts inward from the top to provide ventilation. Doors with large glass areas tend to be less thermally resistant but allow plenty of natural light to enter the home.

Figure 7


Good quality doors can be made from various materials:

  • Steel doors usually have interior components made of wood for strength and stability, an inner core filled with foam or other insulation to improve thermal performance, and an outer skin of galvanized steel for durability and resistance to warping. Steel doors can be painted any colour and generally require little maintenance.
  • Fibreglass doors are relatively new to the market and are built the same as steel doors but with a different outer skin. Fibreglass is very strong, durable and thermally resistant.
  • Vinyl doors – another new addition to the market – feature multiple chambers reinforced with wood, steel or aluminum for strength and to prevent distortion. They offer good thermal performance, are resistant to extreme weather and breakage, and require no special maintenance.
  • Solid wood doors are often aesthetically pleasing, strong and durable, but they are less thermally resistant than doors that have insulated cores. They also require regular maintenance for protection from the elements.

What to Look for in a New Door

Look for the following when considering a new door:

  • an energy-efficient, ENERGY STAR® qualified product
  • a high Energy Rating (ER) or a low U-value
  • wood, vinyl or thermally broken metal frames
  • good quality weatherstripping
  • maintenance-free framing materials
  • glazing with low-e and an inert gas fill
  • insulated cores (entry doors only)

List of models – ENERGY STAR qualified sliding glass doors

The ENERGY STAR name and symbol are administered and promoted in Canada by Natural Resources Canada and are registered in Canada by the United States Environmental Protection Agency.