The Basics of Exterior Doors
Exterior doors are used for entering or exiting a public or private building. They also serve as emergency exits in case of calamities such as fire, terrorism attacks, or other events that can endanger the lives of people inside a building.
Today, entry doors are required to be accessible to everyone, including those with disabilities, by the Americans with Disability Act (ADA) and the International Building Code (IBC). Exterior doors are also used for loading and unloading trucks and can be created in different sizes to serve this purpose.
1. Types of Entry Doors and their Components
Some of the popular door types used by property owners include:
- Swing doors
- Revolving doors
- Industrial doors. These are often used for security purposes and material handling
These door types are made from different materials such as:
- Aluminum
- Steel
- Wood
- Glass
The positioning often determines the type of door material. For example, storefronts can have full-glass doors or aluminum ones fitted with glass in-fills. For exiting and entrance functions, steel-clad doors are preferred. Wood entry doors are primarily used in residential buildings that do not have a lot of activities taking place.
Exterior doors in commercial places are used for material handling and security. There is a lot of movement of both light-weight and heavy-duty vehicles. Steel, stainless steel and aluminum are used in making these doors. Most of these doors are motorized because of their size and weight to ease their operation.
2. Fundamentals
a. Egress
Egress of a door is governed by Chapter 10 of IBC and other applicable building codes. To determine how the building is used, door type and occupancy load are considered. The minimum and maximum door height and width are also determined using this criterion.
b. Accessibility
Exterior doors should be accessible to people using aids of movement such as wheelchairs. According to the building codes and chapter 11 of IBC, doors should not contain obstacles so that people using such aids can pass effortlessly.
c. Thermal Performance
A building’s thermal envelop is often affected by an exterior door’s performance. When faulty, it can allow heat loss and gain inside the building when not needed. A door’s thermal performance is affected by the efficiency of its weather-stripping, glazing, frame perimeter details, and door materials.
d. Moisture Protection
The type of glazing, weather stripping, and frame details affect an exterior door’s moisture resistance. When comparing out swinging with inswinging entry doors, the outswinging ones have better water resistance. This can be attributed to the positive wind pressure against the weather stripping and the threshold leg’s upturning.
e. Visual
These are the visible features of an entrance door, such as glazing, frame sightlines, and glass.
f. Sound (Acoustics)
Doors can be used for soundproofing. Because air leakage is primarily responsible for affecting an exterior door’s soundproofing properties, a few measures can be taken. The mass of the frames can be increased, improving the tightness of frame to perimeter and sash to frame joints, as well as enhancing the airtightness of a glaze.
e. Safety
The operation of an exterior door should be safe for the users. That is, if a door is motorized, it should have a safety system in case it encounters a technical hitch. This way, hazards such as crushing and pinching can be avoided.
g. Health and Indoor Air Quality
Indoor air quality can be affected by toxicity caused by molding. Mold comes when a surface is exposed to moisture for prolonged periods.
Exterior doors should not encourage mold growth to avoid exposing those using the building to toxicity. Double-wall vestibules, walk-off mats, and revolving doors are some measures that can be used to curb this problem.
h. Maintainability and Reparability
Entry doors and sealants are regularly maintained to prolong their longevity. When done properly, they can serve for 5-10 years. When not well prepared and installed, they can be faulty from the very first day.
Materials like ungalvanized steel are susceptible to rust. Therefore, they require regular maintenance and inspection to ensure they do not corrode quickly after exposure to moisture. Galvanized steel, however, offers more resistance to paint, making it last longer. Hollow steel doors rust regardless of the amount of care given provided they are exposed to moisture.
Door hardware should be inspected, adjusted, and lubricated frequently.
