Slammin’ Steel Doors

I am considering replacing my warped, leaky wood front door with an insulated steel door for lower utility bills and greater security. I’ve seen attractive steel doors that resemble natural wood. Are steel doors a good choice for homes?—Ned B.

For overall performance, efficiency, security, and reasonable cost, insulated steel front doors are difficult to beat. The airtight weatherstripping on steel doors can significantly reduce air infiltration and chilly drafts. Most doors are prehung, so it is not difficult to install one yourself and save even more.

Even though steel is a good conductor of heat and these doors have a steel skin, the thick insulated core gives steel doors a much higher R-value than solid wood doors. The most efficient steel doors have a thermal break between the indoor and outdoor steel skins.

If you have not shopped for steel front doors for a while, you will be pleasantly surprised at how attractive they are. With optional decorative glass and sidelights, it is difficult to distinguish a steel door from a wood door until you actually touch it.

The “natural-wood” steel doors have a stainable coating over the steel skins. The thick coating is applied at the factory and then authentic wood graining is rolled into the surface so you can feel the grain.

Each door manufacturer offers its own staining kits, often in oak and walnut, so you or the installation contractor can produce the natural wood look you desire.

The windows you select for your steel door have a tremendous impact on its appearance, energy efficiency, and security. Having some glass in the door provides natural light so you may not need to have as many lamps on.

Selecting the proper type of glass for the windows is also important. Triple-pane decorative glass is probably the all-around best. The decorative pane, made of glass or crystal-clear plastic, is often sandwiched between two smooth outside panes. This creates two insulating air gaps and makes cleaning easier.

For optimum security, order special super-tough, high-security glass panels that are clear or decorative. These use a break-resistant plastic material that is almost twice as tough as tempered glass.

Although most steel doors look similar, there are significant quality differences. The thickness of the steel skin indicates quality. A slightly thicker steel skin provides significantly better stability, dent resistance, and security against break-ins. The steel skin is measured in the “gauge” of the steel. A lower gauge number indicates a thicker steel. Heavy-gauge steel from 22 to 24 is considered good quality.

The hardware (hinges, latches, etc.) used on the door also indicates quality. An insulated steel door, especially one with a lot of decorative glass panels, can get quite heavy and place a load on the bearings. Ball-bearing hinges will provide the smoothest operation. High-security, triple-point locking mechanisms have two additional latches that operate from the standard single handle. Heavy-duty wood lock blocks inside the door in the latch area are most secure.

All steel doors have a core. Foamed-in-place polyurethane insulation has the highest R-value. Another efficient option is a piece of polystyrene insulation fitted between the steel skins. Magnetic weatherstripping, similar to refrigerator gaskets, provides the most airtight seal. It also has an extremely long life compared to standard compression-type weatherstripping. Adjustable thresholds with a multi-fin sweep seal are common on most of the doors.