Choosing a modern entry door is a little like being a contestant on the old "Let's Make A Deal" game show. You don't know what's behind Door No. 1 or 2, and appearances can be deceiving. A steel door may look invincible when it really is tin - can thin. And another that resembles solid wood may in fact be fiberglass, plastic, steel or a thin wood veneer over a steel core.

This article is designed to guide you through the maze of doors - including the newer (and better) types you might not see on display at your local home center. With it, you should be able to choose a door with the right appearance, performance and price.

The vast majority of exterior doors sold today have steel skins, wood frames and rigid foam insulation cores. Exterior doors also are made from fiberglass, PVC plastic, solid wood and laminated wood, each with glass options galore. Prices range from about $300 for a standard steel door to more than $1,000 for paneled wood doors or doors with leaded glass panes. You can buy bargain steel doors for less, but I wouldn't recommend it.

Hey, wood looking!
Door manufacturers and dealers I spoke to say their remodeling customers prefer doors that at least look like traditional raised panel wood doors. They also want doors to be energy efficient and require little upkeep. Depending on the location, security (against burglars and hurricane force winds) can be an issue, too.

Since wood requires the most maintenance and offers the least energy efficiency, manufacturers have been working hard in the past few years to improve the appearance of doors that look like wood but are made of other materials.

Therma - Tru is the leader in fiberglass doors. Its new Classic - Craft line features a realistic woodgrain texture that you color and seal with stain and varnish. The stain doesn't really penetrate the skin as it would wood, but it accentuates the wood effect as it settles in the "grain" depressions. The Therma - Tru door will fool most people from a distance, but it will not fool a woodworker up close. One big improvement over earlier doors is that the orientation of the woodgrain is architecturally correct for the rails (horizontal) and for the panels and stiles (vertical).

Weather Shield's Signature series door takes a different approach to mimicking the look of solid wood. They sandwich an insulated steel door between two real wood veneer faces. The Pease - brand Registry series doors, meanwhile, feature prefinished resin - core panels that are glued to a hardwood stave core.

Several companies offer stainable steel doors. Some emboss the metal itself, but the more common approach is to apply a plastic coating that is embossed with a wood grain pattern.

The impact of glass
If you plan to install your door behind a storm door, it could limit your choice of materials. While lites are secured with wood molding in wood doors, they are installed with plastic moldings in most steel and composite doors. If the door faces south, is exposed to direct sun and is protected by a storm door, heat can build up between the doors and deform the plastic molding. The problem is even worse if the door is painted or stained a dark (heat absorbing) color. This type of door failure typically is not covered by the manufacturer's warranty. The exception is Therma - Tru, which uses heat - resistant plastic for its moldings.

Energy efficiency
In general, fiberglass and steel door systems with polyurethane insulation cores are the most energy efficient and wood panel door systems are the least energy efficient. Unfortunately, it isn't easy to find hard numbers to prove it when comparing doors.

The National Fenestration Rating Council (NFRC) was created in 1989 to apply a uniform approach to judging the performance of window and door systems. It evaluates the doors themselves plus the hinges or sliding mechanism, the jamb, sill, seals, sidelites and locks. The U - factor indicates the amount of heat that passes through the door. U - factors are calculated by placing a door or window in a controlled environment that is hot on one side and cool on the other. The smaller the U - factor, the less the heat transfer from one side to the other. For example, a door with a U - factor of 0.30 will lose half the energy of a door with a U - factor of 0.60.

U - factor testing is voluntary. While some manufacturers use this measure to rate their patio doors, we only were able to find one - Peachtree - that applies it to its entry doors. John Swanson, editor of Fenestration magazine, explains that entry doors are harder to test because the components such as doors, jambs and thresholds often come from different sources and are assembled by the dealers - not the door companies.

In addition to measuring overall energy efficiency, the NFRC also rates solar heat gain, visible light transmission and air leakage. The solar heat gain measure would be more important in Arizona or Florida, whereas the air leakage would be more critical in Alaska.
To get an idea of how different door materials compare, consider the U - factor ratings for flush - type wood, steel and fiberglass doors from the NFRC's most recent (1996) Certified Products Directory. Keep in mind that the smaller the number, the better the performance: solid wood, 0.42 to 0.54; steel, .015 to 0.19; fiberglass, 0.14 to 0.15.

According to the NFRC, today's door lites are three times as energy efficient as the ones that were used in the early 1980s. Advances in door lites are comparable to those in windows - use of multiple layers, heat - reflecting coatings and low - conductivity gases such as argon and krypton seals also have improved.

Steel doors
Better quality steel doors use 22 - or 24 - gauge galvanized steel skins. Budget doors use thinner (26 - gauge) steel that is only primed, not galvanized. These doors are weaker and more susceptible to rusting. Better doors also are reinforced with wood or steel behind the hinges and locksets.

While residential steel doors have steel skins on both sides, the edges are plastic or wood so they don't conduct heat and cold from one side to the other. Without this "thermal break," the doors would frost, sweat or freeze shut. Unlike wood doors, steel doors are not affected by changes in humidity, but they do expand and contract with extreme temperature changes. That's why quality weather - stripping is so important.

Stanley's popular, raised - panel Weather - Wise door system comes factory finished with a plastic composite jamb that is impervious to insects and rot. The door itself is filled with CFC - free polyurethane insulation.

Wood doors
Solid wood doors are made from both hardwoods and softwoods. Because hardwood is expensive, these doors are often custom made with special carving or fancy glass. While oak is most popular, tropical hardwoods such as Honduras mahogany and teak are available. Softwood doors - Douglas fir, western hemlock and pine - are less costly, but it is even more important to maintain them well. To prevent warping and rot, all edges must be sealed with exterior - grade paint or varnish.

In many ways, engineered wood doors are better than solid wood doors. In particular, laminated, finger - jointed or composition frames are less prone to warping because they lack long, continuous - grain orientation. Veneer skins also allow the use of insulated cores.

Manufacturers of wood windows and doors have a quality - rating system established by the National Wood Window and Door Association. The products are tested and rated for resistance to outside physical load, operating force, air infiltration, water penetration and structural performance. Depending on the results of the tests, the wood product is given a rating of Pass (meets minimum requirements), Grade 20 (suitable for residential construction), Grade 40 (suitable for light commercial construction) or Grade 60 (suitable for heavy commercial).

Fiberglass doors
Fiberglass doors have been available for about 15 years. They cost about $100 more than comparable steel doors. Fiberglass doors are durable, stable and require little maintenance.

When selecting a fiberglass door, pay special attention to the proportion of the rails and stiles and the orientation of the woodgrain pattern. If the framework seems narrower than you would expect on a wood door or if the woodgrain texture orientation would be wrong, keep looking until you find a more authentic wood - door look.

Climate considerations
Sun, heat, cold, wind and water all affect door and finishing materials to some degree. For folks who live in the South, solar heat gain and UV radiation are important factors. Some manufacturers make glass products specifically designed for use in the South.

Doors in coastal regions must contend with salt spray, heavy winds and rain. Following Hurricane Andrew in 1992, Dade County, Florida, instituted many code changes to reduce the destruction and loss of life in the event of a hurricane. To obtain a hurricane rating for opaque (without glass) doors, they must pass a missile impact test - a 9 - pound 2x4 ramming at 34 mph.

Alaska's strict energy code has stringent requirements for doors because the temperature ranges from minus 60 degrees F in the winter to 100 degrees F in summer.

Security measures
You don't have to sacrifice aesthetics for security in an entry door. Multipoint locking systems, which are found on most patio doors, are also available as an option on several brands of entry doors. Some multipoint locks have two or three lock points on the jamb; others employ bolts that project into the top frame and the sill. You can also increase security by selecting an entry door with little or no glass and without glass sidelights, or you may opt for a product that offers high - security glazing such as Pease - Shield break - resistant glass. Pease also offers a door lock with an intruder alarm built into the lockset.
Handyman Club member Robert Gould is the former executive editor of Workbench magazine. He writes from Stanley, Kansas.

Sources
- National Fenestration Rating Council, (301) 589 - 6372 or, NFRCUSA@aol.com- National Wood Window and Door Association, (800) 223 - 2301, www.nwwda.org
- Andersen Windows, (800) 426 - 4261
- Benchmark, (800) 755 - 3667 , wdi@mailw.starnetinc.com- Caradco, (800) 238 - 1866 ext. 99 , www.caradco.com
- Hurd Millwork, (715) 748 - 2011; Loewen, or info@loewen.com, www.loewen.com
- Marvin, (800) 346 - 5128 , www.marvin.com
- Owens Corning, (800) 438 - 7465; Peachtree, (800) 477 - 6544 , www.peachtree.com
- Pease, (800) 883 - 6677; Pella, (800) 847 - 3552 , www.pella.com
- Simpson Door, (800) 952 - 4057
- Stanley, (800) 521 - 2752, www.stanleyworks.com
- Therma - Tru, (800) 537 - 8827; Igormex, S.A., (800) 460 - 8227
- Weather Shield, (800) 477 - 6808 , www.weathershield.com