Volume 40, Issue 9 September 2005
Application Guidelines for Fully
Tempered Glass Entrance Systems
Framing applications for fully tempered heavy glass doors and entrances vary depending upon specific job requirements such as the size of opening, reinforcement to meet wind load conditions, hardware and the design of basic structure.
Aluminum channels 3-mm (1/8-inch) thick are used often as perimeter framing when surrounded by solid structure (wood, masonry, marble, concrete, etc.). These channels can be clad to match the metal finish of the doors and patches. This article looks at hardware and accessory guidelines for installation when it comes to such applications. The information is reprinted with permission from the Glass Association of North America’s Fully Tempered Heavy Glass Door and Entrance Systems Design Guide.
Different types of accessories are available from various manufacturers. When selecting operating hardware (i.e. closers, pivots, etc.), the designer should consult the hardware manufacturer’s design limitations, so as not to exceed the maximum recommended sizes and weights for the hardware system selected. If additional information is required, contact the manufacturer or consult the company’s literature.
Accessory types include:
• Center lock housing/strike housing;
• Patch latch lock set;
• Electric locks/strikes (push button, electrical access controls, security/alarm systems, magnetic locks, electric dead bolts);
• Exit device/panics (rim/mortise, exposed vertical rods);
• Lock indicators; and
• Balanced door hardware.
Storefront and entrance system manufacturers supply a variety of products that make it possible for the architect to select systems with a broad range of appearance and structural properties. Manufacturers’ specifications should be referenced for detailed installation instructions … In order to achieve a satisfactory installation, the installer must become thoroughly familiar with all of these specifications and requirements.
The quality of performance achieved in an entrance depends on three factors:
• Manufacture; and
These three stages of work may be the responsibility of three different parties:
• The architect;
• The manufacturer; and
• The installing contractor.
The end result, therefore, necessarily depends on intelligent cooperation and teamwork. In any event, the importance of proper installation cannot be overemphasized. No entrance, however perfect its design and manufacture, will function properly unless it is installed correctly. Unless its frame is plumb and square, and is firmly secured to solid supporting construction, with adequate provision for anticipated movements due to seismic or thermal effects, poor performance and dissatisfaction will very likely result.
The opening in which the entrance is to be installed must be sized correctly, with plumb jambs and level soffit or header. Another consideration regarding the opening is the floor and head condition, not only in the plane of the closed door, but also in front of and through the swing area of operation of the door. Unleveled floors can cause the door to bind in one area with excess clearance under it at the locking position. This will keep the lock bolt from engaging. Since fully tempered glass cannot be modified or re-fabricated, it is important that shop drawing measurements be field verified. If the recommended tolerances are not held, problems are immediately created for the installer of the entrance. If heavy tempered glass fins are required, they must be properly anchored to structurally adequate supports.
Installation of Closers and Pivots
The installation of door closers and pivots requires a high degree of precision. If the door is to operate properly, it is essential that the closer and pivots be installed plumb to each other and level.
Because floor closers are embedded in the floor, care must be taken to ensure floor reinforcing, electrical conduits or ventilation ductwork do not interfere with the closer installation. Sometimes the process is complicated by the necessity of placing the closer housing, or cement case, in its exact location before the finished slab is poured. Often floor closers are located very near the concrete floor slab edge, so care must be taken to ensure that the closer is supported adequately.
Concealed overhead closers are generally installed in an aluminum header that is attached to either the vertical or horizontal load carrying structural supports. The header must be installed level and the closer spindle must be aligned and plumb with the bottom pivot.
When “pivot only” doors are used they should be locked in either the open or closed position. Again, it is essential that the pivots be mounted plumb and level and secured to a load carrying structural member.
Fully tempered glass doors are heavy, so when securing the perimeter frames, door closers and pivots, proper and adequate anchorage to load-bearing structural members is required.
Sidelites, transoms and structural fins must also be anchored to the building structure securely.
Hardware Installation and Adjustment
GANA suggests that certain critical door hardware items, such as pivots, locks and panic exit devices, be factory installed, reducing the chance that misalignment will interfere with proper operation. Installing panic exit hardware, for example, is a critical installation because faulty operation may prevent emergency egress.
Door closers installation is also a critical operation and must be done in strict accordance with the manufacturer’s instructions and templates. If the closer is improperly located or mounted, proper operation will be affected.
Final operational adjustment of all hardware should be made by the entrance installer after all glazing is completed and the building is ready for occupancy. Some types of swing door hardware, such as pivots, may permit vertical adjustment. Concealed overhead and floor closers can be adjusted to center the door. All closers should be adjusted in the field to obtain proper door closing sweep and latch speeds. Patch fitting screws should only be hand-tightened until final adjustments are made. Then the screws should be torqued to approximately 13.6 N-m (10 ft-lbs) to ensure proper glass clamping force. Typically, two screws are accessible from one side of the patch and one is accessible from the other side. All screws should be checked for proper torque. Over-torqueing the screws can strip the threads on the bolt or patch fitting and should be avoided.
© Copyright 2005 Key Communications Inc. All rights reserved. No reproduction of any type without expressed written permission.