Insulation, Aesthetics If you live in a three- or four-season climate and your garage is attached to your home, or if there's finished space like a guest room over your garage, an insulated door makes sense. Not only does it cut down on cold but it also dampens noise and makes the door skin less vulnerable to denting. A steel-door "sandwich" made of thick-gauge steel outer skin, a core of insulation adhered to this skin and a light-gauge backing material of steel or plastic make a very strong but lightweight door. The thickness of this insulation can range from a thin sheet of polystyrene to as much as 2 in. of polyurethane or polystyrene, with resulting R-values ranging from 5 to 10. However, you need to be sure you're comparing apples to apples when shopping. Most manufacturers measure the R-value based on the overall door, but some base their numbers on the center of a panel, which produces a higher R-value. Some plastic doors, as well as some top of the line wooden ones, come insulated. Rubber bulb or flange weathersealing at the bottom of the door completes the stormproofing while keeping dirt, debris and water out. Looks count. A garage door can be a big part—up to 30 percent—of the front exterior of your home. All major companies offer numerous options to add a bit of style to a standard door. You can choose a basic frame-and-panel design or elaborate, sculpted segments. If you own a contemporary home, you might consider a door with bands of horizontal ribbing, or a nontextured flush door design. Generally, the color palette for garage doors is limited to white, beige and brown. However, Gadco offers blue, grey, hunter green and deep crimson on some of its doors. If you're truly picky when it comes to color, painting your metal door—or painting or staining a wood one—is an option. Windows, available as snap-in or screw-in units, come in a wide variety of styles, from basic rectangular lights to multipanel sunburst patterns. For the privacy-conscious, "etched" or colored panes admit light but don't allow a clear view of the garage interior. You'll have to do some prioritizing when deciding on a window material: Acrylic panes are less likely to shatter under impact, but they lack the thermal benefits that laminated glass offers. If the above options don't fulfill your appetite for individualism, think about investing in a custom door. Designer Doors, of River Falls, Wisconsin, hand-builds carriage-type doors of any style that appear to slide, fold or swing outward but actually roll up overhead, allowing them to be used in conjunction with an automatic opener. Holmes Door also makes a carriage-house door that swings up to open.