Steel Doors and Frames 101

October 14, 2022

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While there are a variety of building materials that are used for entryways, we’re here to give you a comprehensive look at steel. You might already know that steel doors and frames are known for being extremely durable and can stand up to all kinds of abuse. Even though this is likely not the first time you’ve heard about this material, we’re going to go through a basic rundown that will help forge an understanding of all the benefits steel doors and frames bring to building projects.   

A Breakdown of Steel Doors and Frames 

First off, it’s common to hear about these doors and frames mentioned as “steel” or “hollow metal” in the industry. Hollow metal doors are composed of two steel skins, one being an internal core that can be composed of a variety of materials including laminated honeycomb, polystyrene, or a welded steel stiffened core. This is what the word “hollow” and there’s either a laminated core or a steel stiffened core that can be laminated or welded. Most hollow metal doors are also manufactured to have mounts for hinges.  

The other piece of the overall structure for hollow metal doors is the frame. Hollow metal frames are built by taking steel sheets that are rolled into a specified thickness and bent to shape the door profile.  

Fire Rating for Steel Doors and Frames 

With steel doors and frames, one of the main benefits that is talked about is the materials fire rating. Fire-rated doors play a critical role in not only helping a project meet safety standards but protect against loss of life and property damage should a building catch fire. Fire ratings range from 20 minutes to three hours and every fire door must meet the standard of the National Fire Protection Agency (NFPA). Steel or hollow metal is the only material that has a three-hour fire rating.  

One of the main reasons why steel doors and frames have become a good choice for a project is that many building codes require fire rated openings to be attached to walls that require their own fire rating.  

In the event of a fire, a temperature rise door (which are required in many cases) is fire rated and will significantly reduce the rate at which heat is transferred to the other side of the door. It’s important to note that fire ratings and temperature rise ratings are separate are different rating systems. In fact, it’s common for openings in a structure to have a fire rating while requiring a temperature rise rating is far less common. The core of these steel doors and frames are specially designed to give people more time to get to safety.  

The Two Main Types of Steel Door Frames 

With steel door frames, there are generally two main types. KD frames come in separate pieces that are assembled and installed into an existing door opening. Welded steel door frames are built and delivered to the job site all in one piece. From there, the frame is set in place and material is built around it. There are also different types of welded frames, which include:  

  • Face Welded Frames: This type of frame is one of the most used in the industry. Face welded frames only have welds connecting the jambs to the header at the faces.  

  • Continuously Welded Frames: The joints along the perimeter of the frame are all continuously welded including the stops, rabbet, soffits, returns, and faces.  

Steel Doors and Frames are Environmentally Friendly 

As one of the most recycled materials in the country, many steel doors and frames are made from reused materials. More and more building projects these days are looking for ways to introduce more green initiatives. One of the great aspects about steel is that it can be recycled again and again. Other materials like wood for example often degrade during the recycling process.  

The Leadership in Energy and Environmental Design (LEED) is a big supporter of steel doors and frames because of its sustainability. In fact, steel not only improves the environmental impact of a project, but it can also extend the life of the building as well.  

Learn More About Steel Doors and Frames with HMMA 

The member companies at HMMA are industry experts in steel doors and frames who are committed to moving the industry forward. Explore some of publications and resources HMMA has put together about steel today.