Comparing Door Materials

Comparing Door Materials (Wood, Fiberglass, Steel)

By Andrew P. Kandels


When shopping for a new entry door, one of the choices you’ll need to make is the material for the door. In today’s door market, there are many options. I’m going to focus on comparing the most popular choices: wood, fiberglass and steel.

Sometimes the materials to choose from are limited by your opening. For example, certain sizes may only be available in a particular door material. A popular example is the curved top entry door, which is usually only found in wood.

There are very few differences in quality when comparing different door materials. A well-produced steel door will last just as long as a fiberglass one. There are well-built and poorly constructed versions of any door, so if you’re worried about getting the most durable door, first start by selecting a reputable door manufacturer that’s had success with their product. And as always, you get what you pay for. Avoid the inexpensive home store brands if you’re seeking longevity.

The biggest difference between materials is aesthetic. For example, people sometimes prefer real wood to simulated wood grains, especially if the door is nearby other wood pieces in the home and needs to match as closely as possible; however, as technology emerges, simulated fiberglass wood grains can be stained to custom colors matched to wood trim and are virtually indistinguishable from real woods even up close.


A wood door is usually made with a thin piece of plywood or laminate on either side with a thicker piece of hardboard backer behind it. The core is an energy efficient polyurethane designed to insulate. The panels are generally done with thicker plywood and wood pieces (much like cabinetry). This is the most efficient way to build a wood door in our climate; however, it does come with many problems especially in northern climates.

Anytime real wood (especially plywood or laminates) is exposed to the elements there will be problems. It won’t be maintenance-free, and it will need to be refinished down the road. The thin laminates or plywoods usually can’t be sanded or can be sanded and refinished only a minimum number of times. The coverings will absorb moisture (many times from the inside, behind the protective clear coat finish) and they will peel or bubble out. Fading is always going to be a problem. A storm door will be necessary, but will also cause problems with the greenhouse heat it will create between the new entry door and the storm door’s glass.

The second type of wood door you can find is a solid wood door (not to be confused with a solid core wood door, which was just described). A solid wood door is 100% wood, through and through. It is by far the heaviest, most secure and beautiful door you can purchase. From a high quality manufacturer, they will resist most major shifting and expanding, although in wood this is always a risk. They will need to be kept up annually or there will be problems with the finish, but these doors can always be sanded and refinished down the road. The major disadvantage to a solid wood door is price. These doors are the most expensive door you can buy, running as much as ten times or more the cost of a steel door.

A new type of door made by Wausau Door Company is a steel/wood hybrid. It’s a great energy-efficient alternative. It’s made identical to a real wood door on the interior, and can be stained and finished to match trim, furniture, etc. It can even be refinished later. The exterior of the door is made with steel, protecting the unit from the elements.

Wood is generally the most expensive door you can buy. Even the steel/wood hybrid door is the most expensive of Wausau Door Company’s door line. If you’re looking for a real wood door, expect a hefty price tag. If you find a cheap wood door, stay away. A poorly constructed wood door will lead to nothing but problems.


It’s important to note the huge range in quality and price when looking at steel doors. The most important thing to note when buying a steel door is the gauge. The higher the number, the thinner the steel.

24-gauge steel doors are commonly found when you’re shopping for an inexpensive door, such as those found at home stores. This is a good temporary solution, but don’t count on it to last. Rusting and paint chipping is quite common. 24-gauge steel is practically paper thin, and it bends and flexes very easily with nothing but insulation behind it. This flexing causes the paint to chip off, which in turn leaves the steel unprotected and free to rust.

22-gauge steel doors are primarily for the home market. It’s a thicker steel that doesn’t bend or flex as easy as a 24-gauge, holds paint extremely well, and can have a simulated wood grain cut into it that provides for a wood appearance when finished with a gel-based stain. It costs a little more than the 24-gauge doors, but the difference in quality is huge.

There are doors available in thicker gauges of steel, but these are primarily for the commercial or security markets.

Today, steel is the common choice for door replacements. It’s inexpensive (when compared to other materials), secure, very low maintenance and comes in a large variety of styles and colors to suit your needs.


Fiberglass is a relatively new material in doors today. It’s very low maintenance, resists denting and scratching, and is very strong and secure. It also offers a wood grain if you desire a wood-look.

Quality is huge in fiberglass doors (much like wood doors). Stay away from the cheap brands if possible. Cheap fiberglass may crack (especially in cold weather) and fall apart. Its finish may deteriorate quickly and the inner core could rot. If you’re looking for a cheap door, consider the inexpensive steel ones first.

Another benefit to fiberglass is that unlike wood and steel, it doesn’t need to be finished to be considered low maintenance. Fiberglass, even when left unfinished, will last for years without fears of mold, deterioration, or rust.

A very important thing to note in fiberglass doors is the quality of their wood grain. When Therma-Tru originally developed the first wood grained fiberglass doors, they used multiple dyes to give the grain random depths. This technology was patented, and although some manufacturers tried to copy it, Therma-Tru still makes the most impressive wood grain in a fiberglass door to date. This is called random depth graining, and is combined with thicker, more detailed panels and real wood square side panels to top it off.

Most fiberglass doors such as those found at home stores will offer only one or two depth wood graining. In combination with a cheaper grade fiberglass and cheaper panels, you could purchase a wood grained fiberglass door for only a few hundred dollars. Although this may seem like a great deal, don’t be fooled. These doors have nowhere near the realistic wood graining and are not built to last. About 50% of our business comes from replacing these types of doors in newer homes because of door failures or because the homeowner’s simply wanted a better looking and working door.

On our website, we offer pricing for two brands of fiberglass doors: Wausau and Therma-Tru. Wausau makes a high quality fiberglass door but does not offer the detail of random depth graining. These doors are more affordable. The second option, Therma-Tru (described above) offers random depth graining and is virtually indistinguishable from real wood (at a higher cost).


The quality of a new entry door depends more on the quality of the installation and the product than it does the material. Once you’ve determined the materials available to you, sort your final decision by the look and price you desire in your new door.

If you’re not looking to spend a lot of money, stay away from fiberglass and wood. A cheap steel door will be the best investment of the three. Otherwise, quality built models of each material compete with each other very well.