High R Value Exterior Doors

For example a 1 1 2 inch 3 81 cm thick door without a window offers more than five times the insulating value of a solid wood door of the same size.

High r value exterior doors.

Rustica s french style sliding barn doors entry doors and rustica s replacement windows have the most efficient r value on the market listed at 3 94 for interior doors and replacement windows and 5 31 for a 2 1 4 exterior door. This is a huge difference and essentially comes down to astm c518 being a theoretical maximum based on a steady state thermal test of only a portion of the door panel. A 2 1 4 inch solid core wooden door for example has an r value of 3 70. Feather river doors 63 5 in x81 625in mission pointe zinc 3 4 oval lt unfinished smooth right hd fiberglass prehung front door w sidelights model 182191 3a4 70.

When determining how much insulation you need don t guesstimate calculate. Therma tru fiberglass doors have a solid polyurethane foam core which is among the most energy efficient door materials available today. An insulated steel or fiberglass will have an r value that is twice as good generally r 5 to r 6 but in some cases as high as r 7. The r value of a 1 3 4 inch wood door is 3 03.

European manufacturers of passivhaus certified doors advertise r values as high as r 11. R values climb as thickness of the material increases. Most therma tru decorative as well as privacy and textured glass is triple pane for reduced heat flow. Know exactly how much you need with our project calculators.

Some of the features that help therma tru doors earn their energy star qualified ratings include. The r values of most steel and fiberglass clad entry doors range from r 5 to r 6 excluding a window. The higher the r value the greater the insulation performance. Glass inserts also cut the door s insulating value though double or triple panel glass reduces that effect.

In new homes especially in cold climates in very energy efficient buildings look for the best performance doors possible. A polyurethane foam core. R value measures how well certain building insulation materials can resist heat.