|LEVEL OF SECURITY|
There are three basic categories.
Light: normally with no quoted holding force or life. Usually AC and used for low cost door entry systems.
Medium: Holding force of at least 1,000lb with guarantees of two or three years.
High: Holding force of at least 3,000lb with guarantees of up to five years. Some are available with UL approval.
TYPE OF DOOR
Door material - internal or external, single or double doors.
Electric strikes can only be used on single action inward OR outward opening doors. For double action swing-through doors other locking solutions like solenoid bolts, magnetic shear locks or double action electric latches are available. Nowadays there are strikes suitable for nearly all door styles and materials, the most popular being timber and aluminium followed by steel, and occasionally, uPVC.
Potentially, uPVC causes the most problems because of the narrow and often complicated section containing steel re-enforcing. Another problem is the fitting of a suitable lockcase into the narrow uPVC framing to operate with the strike. If the door contains a multi-point lock it is likely to be impossible to fit an electric strike.
If the door contains, or can be fitted with a latch, the best option could be to fit a narrow style sashlock and operate with a sashlock strike either in a UK or DIN faceplate format.
Whilst a sashlock can improve the level of security in any door when the deadlock is thrown, care should be taken to ensure that the bolt is removed prior to attempting the operation of the strike.
The first quantity usage of strikes was in the United States in aluminium doors and frames. This in turn led to an ANSI (American National Standards Institute) specification being produced. The ANSI short faceplate strike (flat or radius faceplate for single or double doors) became the standard for aluminium, whilst a further development was the introduction of a longer faceplated variant which made the ANSI style strike suitable for use in timber door applications.
With the introduction of centre-hung aluminium doors in a 4 inch (101.4mm) framing section, the need became apparent for lead in or extension lips to allow the latch free entry into the jaw of the strike without interference from the frame. Originally a mix and match of the long and short faceplate variants covered steel doors, whilst products designed specifically for timber and steel doors offering longer shallower and narrower bodies are now available.
Watch out for door gaps. The most commonly sold strikes in the UK operate successfully with no more than 1/8 inch (3mm) gap between the frame and door leaf.