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Fundamental Facts of Walkthrough Doors

Knowing fundamental door components helps ensure a proper install

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A pre-assembled walkthrough door and frame: How does something that sounds so benign and innocuous become a consuming pain point that can disrupt the construction schedule of a building, bring down the wrath of local building code enforcement, and cost thousands upon thousands of dollars in labor and material to set right? Well, it can. Everyone in our industry has had this experience, and every time it occurs there are two resounding questions that arise: “How did this happen?” and “How can it be avoided in the future?” The answers lie in the door order form.

Before we talk order form specifics, it’s worth noting that all else will fail without two basic, but key, ingredients: communication and information. There must be a clear line of communication between the customer and the supplier. Without this, the first block of the door order pyramid cannot be set. The key information required to successfully order a walkthrough door and frame includes the specifications, door schedule and floor plan for the job. How this information is interpreted by the customer, and then communicated to the supplier, is critical. There may be times in which part of this information is missing or unclear. When this happens, the architect or detailer should be contacted for clarification.

Size, Gauge, Core

The nominal door size is where it all begins. Door sizes are listed width by height, such as 3070, 4070, 3080 and 6070. This is also where it needs to be indicated if the door is a single door or a pair of doors. Doors can be manufactured in various widths and heights so specificity is necessary. Next is the gauge of steel. In the metal building industry, steel gauges for doors vary from 12-gauge all the way to 20-gauge. Indicating if the steel is to be galvanized or cold rolled should also be noted at this stage.

The core of the door needs to be established. Door cores can vary. The most common are polystyrene, polyurethane and paper honeycomb. Of the three, polyurethane has the highest insulating properties. Paper honeycomb contains the least.

Ratings and Depth

There are several different types of labeling that can be specified for doors and frames. The most common is fire ratings. These ratings for steel doors are as follows: A–3 hours, B–1 1/2 hours, C–3/4 hour, and 20 minutes. Local fire codes determine which doors require labeling and what that rating should be. Doors and frames can also be wind-rated. These wind ratings are determined by the geographical location and where it falls in the National Hurricane Wind Speed Map. The wind ratings are indicated in PSI, or pounds per square inch of pressure. This information should be indicated in the door specifications and on the door schedule of the job.

To determine the depth of the frame and how best to anchor it, you must first know what type of wall you’re working with. Wall types can vary. Metal buildings contain horizontal wall girts, which require the frame to be mounted in sub-jambs for anchoring. We also commonly see existing masonry applications, which require punch and dimpled holes in the soffit of the frame and expansion sleeve bolts for anchoring. Other wall types include interior walls with metal stud anchors with sheetrock, new masonry, wood studs with sheetrock, and even insulated metal panels. The wall type and application is critical for a smooth anchoring and installation process.

Establishing the fundamental information required to place an order for a pre-assembled walkthrough door, and then communicating that information correctly to the supplier, is the solution to avoiding disruptions to the building schedule and staying off the dreaded punch list. Each individual and each company may have different methods of collecting this information, but at the end of the day, no matter the method, the same information is required. Though it seems basic, understanding the information in the door order form is absolutely vital to staying on schedule, saving money and ensuring a proper install.

Scot E. Kelly is sales manager at PDL Building Products, North Olmsted, Ohio. To learn more, visit