Cylindrical Lever Locks

Which Cylindrical Lever Lock Function Code Goes on Each Opening? 

Classroom Doors: Why F05 Is Non-Negotiable 

A classroom lever lock specified to function F05 stays locked on the outside at all times. The teacher can lock or unlock the outside lever with a key, and the inside lever is always free for student egress. That's the correct lockdown configuration. A lot of older buildings have F04 (office/entrance) on classroom doors, which can't be locked from the corridor without propping the button. If you're replacing classroom hardware on a school project, confirm every door comes with F05, not F04. 

Storeroom, Office, and Passage Functions 

Storeroom (F07) keeps the outside lever locked at all times with a key required every use. Correct for server rooms, supply closets, and controlled storage where you don't want someone to sneak in while an authorized user holds it open. Office/entrance (F04) lets the inside occupant lock the outside lever with a button. Good for private offices. Passage (F01) has no locking at all. Use it for restroom corridors, copy rooms, and interior doors where security isn't a factor. 

What Does the ADA Say About Lever Locks on Commercial Doors? 

ADA Standards for Accessible Design Section 404.2.7 requires that door hardware be operable with a closed fist. Knob locks fail this test because they require grasping and twisting. Lever locks comply. On any new commercial construction on an accessible route, lever locks are required by code, not optional. On existing building hardware replacements, the ADA requirement applies if the scope of work triggers an accessibility upgrade. When you're replacing hardware on an existing door that's on an accessible route, check with the project AHJ before specifying knob locks as replacements. 

Which Brand Should You Specify? Key Models by Application 

High-Traffic Institutional Applications 

For schools, hospitals, and government facilities, the Schlage ND Series Grade 1 is the most specified cylindrical lever in the US. It covers every function code, accepts all cylinder types including SFIC prep, and comes in every ANSI finish. Sargent 8800 Series is the alternative for Sargent-standard campuses. Corbin Russwin CL3 is preferred in northeast US healthcare. BEST 9K is the specification for BEST SFIC masterkey programs. 

Budget-Sensitive Projects Without Sacrificing Grade 1 Performance 

Cal-Royal NM Series, Arrow BM Series, Falcon B Series, and PDQ GT Series all carry Grade 1 ratings at a lower price point than Schlage or Sargent. You don't lose the ANSI grade certification. You do lose some brand recognition with AHJ inspectors who've come to expect Schlage or Sargent on institutional submittals. For private commercial projects without manufacturer spec restrictions, these are solid Grade 1 alternatives.