Door Selection

Doors and their associated hardware are an integral part of a school facility that, if not specified and installed correctly, can cause major problems. The costs associated with the failure of a door-opening component can be staggering, and the resulting loss of use potentially devastating.

Specifying products for door openings in the rehabilitation of existing buildings is fairly complex. It is important to gather and analyze information about existing and new door openings and their planned operation before a door, frame, key, cylinder or lock is modified or specified. The older the building, the greater the diversity for door, frame and hardware. Correct specifications for door openings can eliminate unnecessary costs and ensure security.

Taking stock The first step in preparing specifications for door-opening rehabilitation work is to become familiar with all door-opening conditions and requirements. The facility manager should provide all available drawings and specifications, and be prepared to discuss design standards for door openings and the availability of door component "attic" stock.

Door component stock comprises a variety of doors, frames and hardware. If the facility owner intends to use stock, the specifier should confirm the quantity, type and, most important, handling of the items. Attic stock can represent the facility manager's design standard and, in the absence of existing drawings and specifications, may provide valuable answers to questions about design standards. Without attic stock, the specifier should weigh the availability of door-component products carefully against delivery time. The more standardized the product, the more available it will be and, generally, the less it will cost.

Some facility managers maintain design standards to communicate door-opening quality levels, save construction time and costs, reduce parts inventories and establish a predetermined measure of acceptable door-opening maintenance costs and procedures. Design standards often are embodied in guide-specification formats and may include desired door and frame heights and finishes; frame-throat dimensions; hardware finishes; hinge, closer and lock designs; and masterkeying.

Door considerations Some things to consider when specifying doors include:

-Security. Security within the project may range from an inexpensive extension of the existing masterkey system to sophisticated magnetic key-card systems, closed-circuit television (CCTV) cameras and patrolling guards. If the school has engaged a building-security firm, verify if locking devices, including electric strikes, magnetic locks and door-position switches, will be used on the door openings for the project. Security hardware components may interfere with mandatory egress requirements and can have detrimental effects on the structural integrity of door and frame components if the components are not properly sized and reinforced.

-Door and hardware modification. Special consideration must be given to doors and frames that require modification, especially those that are fire-rated. Avoid modifications that require internal door or frame reinforcement. Only modify existing fire-rated doors and frames by a company that is licensed and qualified through the testing agency whose label appears on the door and frame. Many door and frame distributors maintain licensed and qualified shops.

Frequently used doors may have hinge-edge frame and door deformation. If the door and frame are to remain, repair the deformations and replace existing butt hinges with a continuous hinge. A continuous hinge uses a greater number and size of nylon, thereby increasing its resistance to abuse.

Locking hardware. Upgrading door openings to receive mortised electrified hardware is more difficult than installing surface-applied electrified hardware. For electromechanical locks and latchsets, remove existing doors and replace them with doors having new internal, prewired conduit preparations. In addition, retrofit the door frame to receive an electrified transfer hinge.

Probably the easiest electrified lock to install is a magnetic or punched keycard-operated lockset. Keycard locks can be rekeyed at a lower cost than conventional keying. Magnetic and punched keycard-operated locksets typically use lock bodies that fit most existing mortise-lock preparations. They are battery-powered so there is no need for hard wiring through the door and frame.

Electromagnets are the least problematic electrified locks and can be mortised or surface-applied to almost any door opening. However, surface application of these locks restricts the swing of an existing door to only one direction. This may be acceptable as long as the swing is in the direction of egress.

-New and old components. The use of new and old components can be frustrating. Often, new hardware will not match the mounting of the previous lock, latch, pull or similar door trim. Not only can these existing preparations be unsightly, but also they can affect the ability of the new hardware to be mounted properly to the existing door. In these cases, the specifier may use an underplate.

Underplates should be dimensioned and templated properly for the new hardware, while covering the existing door preparations on both door faces. They should be sized to wrap the lock edge of the door and fabricated from a gauge and finish that is compatible with the new hardware. Specialty hardware manufacturers can supply prefabricated underplates to receive many standard mortise and cylindrical lock bodies.

Existing door frames must be field-measured accurately before installing new doors and hardware. During this process, measure each opening for door height, width and thickness. Likewise, accurately field-measure existing doors before applying new hardware. Measure the door stiles and rails to verify whether hardware components can be fitted into or mounted to them.

Functional components Door openings must satisfy the statutory building-code requirements for accessibility and safety of the building's occupants. Depending on location and number of occupants, some door openings need to resist flame spread, smoke penetration, wind and rain infiltration, or positive pressures developed during fire conditions. Some must accommodate persons with disabilities.

Specifiers should determine if the existing door openings and hardware comply with the new use, and then draw, schedule and specify changes or additions to the existing door openings for compliance with building codes.

Existing door width also should be considered, as well as door placement (pull and push sides) and hardware for compliance with the Americans with Disabilities Act (ADA). The closing force of an interior door cannot exceed 240 Pa (5 psf) in order to comply with ADA. A closer pressure gauge normally is used to measure the closing force of an existing door. If the door has a latch that requires a wrist-twisting motion to operate, it should be equipped with a lever device.

During field inspection, it is important to observe life-safety and fire-code violations. Fire-resistance labels attached to existing doors and frames, and the applied hardware, should be verified for compliance with prevailing building codes. Rectify all such violations as an integral part of the rehabilitation drawing preparation, specification and scheduling process.

Rehabilitating doors The specifier or facility manager should look for components that may not be appropriate for the rehabilitation of the project, such as mismatched hardware finishes and trim. Verify existing hardware on door openings for function and determine if they need rehabilitation. Other things to look for include:

-Split lock edges of wood doors.

-Bent latch or deadbolt linkage.

-Warped wood doors.

-Damaged or deformed frames.

-Dented doorknobs.

-Leaking closer hydraulic fluid.

-Chipped door edges.

*-Gouged or dented door faces.

-Natural wood door finish discoloration.

-Peeling paint.

-Excessively scratched lever, knob, pull and push plates.

-Tarnished hardware finishes.

-Worn plated finishes on levers, knobs, pulls and push plates.

-Worn gasketing.

-Rust.

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