Making an Entrance

The story is probably not that uncommon. A door is installed and, a few months later, it is not working properly. While the door manufacturer may be the first one called, the problem often lies elsewhere.

For example, if a light-duty door closer is installed on a heavy-duty door, the result often can be a door that slams shut. Another problem can be the entrance frame header, which often is thin and not reinforced properly to hold the closer shoe securely.

Understanding your entrance An entrance is a system comprised of the frame, the entrance hardware, one or more doors and the installation. These four components are like links in a chain, and the entrance will perform only as well as the weakest of the four components.

Manufacturers have refined the basic entrance-system concepts over the years in response to demands and input from school facility personnel. If adhered to, these concepts will enable schools and universities to acquire entrances that will last for many years with minimal maintenance.

Most educational institutions operate with at least two budgets--a capital budget and an operating budget. Too often, those administering these budgets appear to operate in separate worlds. One of the objectives of those people in charge of the capital budget is to bring in projects at the lowest possible cost, while those living the operating side are trying to keep their buildings functioning. Thus, value engineering for those controlling capital budgets often turns out to mean substituting less-expensive products for those specified; while those responsible for operations define value in terms of lifetime costs--durability, reliability and the expected level of maintenance expenses. To ensure the most cost-effective purchase, it is important that input from those responsible for maintaining completed capital projects be taken into consideration to ensure long-term performance of entrance systems.

Building a foundation The most basic part of an entrance system and, unfortunately, the most neglected component of the entrance is the frame. An entrance's frame can be compared to a building's foundation. Both, if not engineered and placed correctly, will perform unsatisfactorily. If the frame is inadequate, the most substantial entrance hardware and/or the finest door will not make the entrance perform satisfactorily.

The appropriate, built-to-last frame for an aluminum entrance is a .125-inch wall-thickness, aluminum enclosed-tube frame with screw-applied door stops. The enclosed-tube frame provides the strength and rigidity needed for a tough-usage entrance; the applied stop provides enhanced security and is adjustable; and the .125-inch wall thickness provides sufficient metal thickness to secure the entrance hardware. Unfortunately, in an effort to serve the low-bidder market, the aluminum industry standard frame has become .090-inch wall-thickness, open-back, fin-stop or snap-in stop frames.

To the casual observer, once installed, an open-back frame looks virtually the same as a full-tube frame. On the other hand, it is easy to tell the difference between a .090-inch wall-thickness frame and a .125-inch wall-thickness frame. Just tap each with a coin or a fingernail; the .090-inch frame will sound like an empty soda can, while the .125-inch frame will sound like something you would want to hang a door on.

School entrance hardware should be designed to withstand tough and abusive conditions. Many schools are adopting heavy-duty aluminum gear hinges as a standard hinging mechanism. These hinges distribute the load over the full length of the opening, provide an attractive appearance, and deliver long-lived, trouble-free performance.

Closers must be heavy-duty with back-check, closing-force and latching-speed adjustments. The closer should be rigid-parallel arm mount to minimize tampering and abuse. Choose a closer with all-weather hydraulic fluid. Furthermore, especially for ADA compliance, the closer must have a spring-power adjustment. The simplest, most maintenance-free application is a touch-bar rim exit device using a removable mullion in pairs of doors. Exit devices should have a stainless-steel touchbar for long life and attractive appearance. If a lever handle must be used, choose a vandal-resistant, breakaway lever.

The stile- and rail-type door is the most common type used in aluminum entrances. The main advantage is large glass areas that let in light. The main disadvantage is that the large glass area may lead to broken glass. Generally, aluminum stile and rail doors are the first choice where abuse is of minimal concern. A heavy-duty aluminum stile and rail door should have .125-inch wall-thickness stiles and rails. Full-width tie rods joining the stiles and rails are the best to achieve a long-lived door.

Steering clear of problems As is the case with aluminum frames, many aluminum-door manufacturers have introduced stile and rail doors with .090-inch or less wall thickness. The stiles and rails tend to dent on these doors, and there is insufficient metal to properly secure the door hardware. In addition, a number of manufacturers offer stile and rail doors with .1875-inch-thick walls. In many cases, these extra-thick walls are not necessary. They result in the doors being 50-percent heavier than needed, increase the entrance cost, make the doors harder to operate, and put strain on the entrance hardware.

A wise choice is to order a mid-rail option on stile and rail doors. The mid-rail is ideal for mounting the touch-bar exit device and divides the glass into two pieces. A mid-panel that incorporates a flush pull is another popular option. If glass breakage is a problem, a 1-inch insulated panel can be glazed into the lower half of the door. However, as features such as mid-rails and glazed panels are added to reduce the glass area, the cost of the door increases.

At some point it may make sense to start with an aluminum-type flush door. Aluminum flush doors are attractive when initially installed; however, their skins are too tender for hard-usage applications. For tough and/or abusive situations, the fiberglass-reinforced polyester (FRP) flush door is the clear choice. An FRP facesheet on a flush door resists denting and scratching and is relatively maintenance-free. Whatever face-sheet is chosen, consider full-width tie-rod joinery. For superior strength and insulating capability, purchase a poured-in-place urethane foam core.

Also, carefully evaluate the available suppliers for each of the entrance components. Choose brands and models with proven performance and use these to establish entrance standards for the school. Stick with these standards and be sure that architects working on projects in the district are furnished with the standard entrance specifications. Also, make sure the installer is experienced and has earned a good reputation installing hard-usage entrances.

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