An entry door is surely one of the most important visual elements of the building shell. But a door isn't just a pretty face. It must open smoothly and close securely despite exposure to weather extremes, and it must help to maintain comfortable temperatures inside the house by serving as a barrier to temperature extremes.
There are three basic door construction typeswood, steel, and fiberglassbut there are many national and regional door manufacturers, so choosing a door can be challenging. Note that large manufacturers usually offer similar-looking products in various grades to suit different budgets. And if none of the many choices of stock doors suit your requirements, some manufacturers will custom build a door to your specifications.
Key Specifications
Size typeRefers to the distinction between doors available in stock sizes and those manufactured to custom specifications. Most manufacturers of wood exterior doors offer standard heights of 6 feet, 8 inches; 7 feet and 8 feet. Stock widths generally start at 2 feet, 0 inches and run up to 3 feet, 6 inches in increments of 2 inches. Stock heights for fiberglass and steel doors are generally limited to 6 feet, 8 inches and 8 feet. Custom sizes may be available by special-order but inevitably comes at significantly higher cost. Exterior doors are typically 1-3/4 inches thick.
Nominal dimensionsThe nominal width and height of a door refers to the dimensions of the door itself, not to the frame. They are given in inches, or in feet and inches (for example, height may be noted as 82 inches or as 6 feet,10 inches).
Wood speciesIn the case of veneered wood doors, species refers only to the face veneer and is primarily an aesthetic consideration. With solid wood doors, however, species is the most important determinant of the door's dimensional stability, durability, and cost.
Color/FinishEntry doors are available either unfinished or with a factory-applied finish (in the case of steel doors, unfinished means the door is primed). Unfinished products are the best option if the door has to match existing finishes or colors, and they are somewhat less expensive than pre-finished doors.
Panel shapeTraditional panels are square or rectangular. A slightly more costly option incorporates a shallow arch shape called an eyebrow or a more rounded shape called a radius.
Panel styleThis refers primarily to the shape of the panel as viewed in cross-section. Panels that are thicker at the center than at the edges are called raised panels, while those with a consistent thickness are called flat panels or Shaker panels. Cross-buck doors feature raised panels that are triangular in shape; they fit within an X-shaped configuration of rails at the lower half of the door.
LitesUnits of glazing within a door's overall design. They increase the visual impact of the door, but their primary advantage is in admitting natural light to dark entry halls.
Lite configuration The number, size, and location of lites have a substantial effect on the security of the door as well as on its energy efficiency.
Top profileMost doors have a squared-off top. Arched-top or radius doors offer a dramatic appearance.
Types of Door Materials
Solid woodWood is the material of choice for many people, in part for its traditional look and warm, inviting appearance. Wood doors are available to suit any architectural style, and they can be detailed to create a unique product particularly suited to high-end construction. Wood doors are available in both softwood and hardwood species, though some are readily available only within a particular region. The choice of wood depends on the desired appearance, but be sure to consider climate and the door's exposure.
Weather extremes are hard on a wood door, resulting in increased maintenance requirements. One way to minimize the impact of weather is to protect the door with a storm door, especially if the door is not shielded by an entry porch. A storm door will also tend to improve energy efficiency because a wood door alone has an insulating value of only R-2 or so. In areas where insect activity is significant, consider doors made from wood that have been preservative-treated to resist rot, insect attack, and moisture absorption.
One advantage of wood doors is that they can easily be trimmed to fit odd-size or un-square openings. Neither steel nor fiberglass doors can be trimmed.
SteelA steel door is a composite construction. The door skins (the front and back surfaces) consist of 24-gauge to 26-gauge galvanized steel that are often shaped to replicate the look of a wood frame-and-panel door. The perimeter of the door should ideally consist of wood stiles and rails to provide a thermal break between outside and inside surfaces. High-density polyurethane insulation fills the space between the two skins, resulting in a stable, energy-efficient door that does not require a great deal of maintenance.
The insulating value of a steel door is may be as high as R-15, but the overall energy performance of the door can be improved with magnetic weather-stripping that forms a good seal when the door is closed. Steel doors can be dented, but dents are relatively easy to repair. Steel doors should be painted; they won't accept stain. Some are available with a factory-applied final finish, though in a limited number of colors.
FiberglassSimilar in construction to a steel door, but with fiberglass door skins, a fiberglass entry door has an insulating value that may range from up to R-15. In a high-quality fiberglass door, the skins can be textured so that the surface appears almost identical to real wood. Fiberglass can be stained to enhance the similarity further. Because fiberglass is a more resilient material than steel, it is more resistant to denting.
Entry Door Materials: Relative Cost | ||
<Less Expensive/More Expensive> | ||
Steel | Fiberglass | Solid wood |
Door lites and glazing details
Glazing is sometimes thought of primarily as a decorative element, but the addition of glazing should not be considered lightly. Glazing, either in the form of large panes or smaller lites, can dramatically increase the cost of a door as well as reduce its energy efficiency and security. Though single-glazing is available, it is generally most suited for use on entry doors located on garages and outbuildings.
Glazing Details: Cost and Energy Efficiency | |||
<Less Expensive, Less Efficient/More Expensive, More Efficient> | |||
Single-glazing | Double-glazing | Double-glazing,low-e coating | Triple-glazing |
Other glazing factors can increase door costs as well. Glazing options include decorative etched glass, stained glass (lead or brass caming costs more than plastic caming), and the inclusion of high-strength outer glazing for security purposes. The arrangement of glazing is sometimes described by its location or by how much of the door it fills. In a 1/2-view door, for example, the upper half of the door is glazed. In a top-view door, lites are located only in the uppermost portion of the door.
Other factors to consider
In some parts of the country, local codes may require entry doors withstand a certain amount of damage caused by wind-blown debris. Check these requirements before choosing a door.
Entry doors are generally available either as a slab (the door only) or as pre-hung units (mounted on hinges attached to a door frame). One variable in pre-hung entry doors is the threshold. Some may come with an integral threshold, while others may require a separate threshold. Another factor to consider is the threshold material. Aluminum is strong and weather-resistant, but a solid-wood threshold may be more in keeping with the architectural style of the house.
A lightweight storm door helps to protect a wood door from the weather. A fiberglass or steel door may not require this protection, however, and in fact may actually be harmed by the addition of a glazed storm door. If the door is exposed to hours of direct sunlight, heat build-up between the two doors can damage the entry door finish or in extreme cases, even warp the exterior door skin.
Additional Information
American Architectural Manufacturers Association
www.aamanet.org
American Institute of Architects (AIA)
www.aia.org
American National Standards Institute (ANSI)
www.ansi.org
American Society of Civil Engineers (ASCE)
www.asce.org
Associated Builders & Contractors (ABC)
www.abc.org
Associated General Contractors of America
www.agc.org
Association of Window & Door Installers (AWDI)
www.awdi.com
ASTM International
www.astm.org
Blue Book of Building & Construction
www.thebluebook.com
Builders Hardware Manufacturers Association
www.buildershardware.com
Building Codes Assistance Project (BCAP)
www.bcap-energy.org
Building Officials and Code Administrators (BOCA)
www.bocai.org
Building Trades Directory
www.buildingtradesdir.com
Construction Specifications Institute (CSI)
www.csinet.org
Door and Access Systems Manufacturers Association
www.dasma.com
Door and Hardware Institute
www.dhi.org
Efficient Windows Collaborative
www.efficientwindows.com
ENERGY STAR
www.energystar.gov
Glass Association of North America
www.glasswebsite.com
Glazing Industry Code Committee
www.glazingcodes.org
Insulating Glass Certification Council (IGCC)
www.igcc.org
Insulating Glass Manufacturer's Association
www.igma.com
International Conference of Building Officials (ICBO)
www.icbo.org
International Window Film Association
www.iwfa.com
National Association of the Remodeling Industry
www.remodeltoday.com
National Fenestration Rating Council
www.nfrc.org
National Fire Protection Association (NFPA)
www.nfpa.org
National Glass Association
www.glass.org
National Institute of Building Sciences
www.nibs.org
Northeast Window & Door Association
www.nwda.net
Occupational Safety and Health Administration (OSHA)
www.osha.gov
Protective Glazing Council
www.protectiveglazing.org
Safety Glazing Certification Council (SGCC)
www.igcc.org
Screen Manufacturers Association
www.smacentral.org
Steel Door Institute
www.steeldoor.org
Steel Window Institute
www.steelwindows.com
U.S. Department of Energy, Office of Energy Efficiency and Renewable Energy
www.eere.energy.gov
Window & Door Magazine
www.windowanddoor.net
Window & Door Manufacturers Association
www.wdma.com