City of San Mateo Law Library
City of San Mateo Municipal Code.


(a) Doors.

(1) Exterior doors.

(A) Exterior doors and doors leading from garage areas into single family dwellings shall be of solid core with a minimum thickness of one and three-eighths (1-3/8) inches.

(B) Exterior doors for single family dwellings and garages shall have deadbolt locks with a one (1) inch minimum throw in addition to deadlatches. The locks shall be so constructed that both deadbolt and deadlatch can be retracted by a single action of the inside doorknob. Alternate devices equally resistant to illegal entry may be substituted subject to prior approval of the Building Official. Strike plates shall be secured to wooden jambs with at least two and one-half (2-1/2) inch wood screws.

(C) Doors leading from enclosed garage areas into single-family dwellings shall have deadbolts in addition to deadlatches.

(D) Vision panels in exterior doors or within reach of the inside activating device must be of burglary resistant glazing or equivalent as approved by the Police Department.

(E) Openings for delivery of mail shall be no larger than twenty-four (24) square inches. Openings located within three (3) feet of any locking device shall be constructed to prohibit access to the interior doorknob.

(F) Exterior doors swinging out shall have non-removable hinge pins or hinges with studs.

(G) Exterior doors swinging in shall have rabbited jambs.

(H) Door frames shall be installed or protected to prevent violation of the function of the strike.

(I) Door jambs shall be installed with solid backing in such a manner that no voids exist between the strike side of the jamb and the frame opening for a vertical distance of six (6) inches each side of the strike.

In wood framing, horizontal blocking shall be placed between studs at door lock height for three stud spaces each side of the door openings. Trimmers shall be full length from the header to the floor with solid backing against sole plates.

The strike plate for deadbolts on all wood-framed doors shall be constructed of minimum sixteen U.S. gauge steel, bronze, or brass and secured to the jamb by a minimum of two screws, which must penetrate at least two and one-half (2-1/2) inches into solid backing beyond the surface to which the strike is attached.

(J) On pairs of doors, the active leaf shall be secured with the type of lock required for single doors in subsection (a)(1)(B) of this section. The inactive leaf shall be equipped with lever flush extension bolts or equivalent, protected by hardened material with a throw of three-fourths (3/4) inch at head and foot. Multiple point locks, cylinder-activated from the active leaf and satisfying the requirements above may be used in lieu of flushbolts.

An interviewer or peephole shall be provided in each main entry door and shall allow for 180 degree vision or more.

(2) Sliding patio type doors opening onto patios or balconies which are otherwise accessible from the outside (this includes accessibility from adjacent balconies) shall comply with the following:

(A) Single sliding patio doors shall be adjusted in such a manner that the vertical play is taken up to prevent lifting with a pry tool to defeat the locking mechanism.

(B) Deadlocks shall be provided on all single sliding patio doors. Mounting screws for the lock cases shall be inaccessible from the outside. Lock or hook bolts shall be hardened steel or have hardened steel inserts. The lock or hook bolt shall engage the strike sufficiently to prevent its being disengaged by any possible movement of the door within the space or clearances necessary for installation and operation. The strike area shall be reinforced to maintain effectiveness of bolt strength.

(C) In addition to the primary locking device, auxiliary or secondary locking devices shall be provided on all accessible sliding-glass doors.

(D) Double sliding patio doors shall be locked at the meeting rail and meet the locking requirements of subdivision (a)(2)(B) of this section.

(b) Windows.

(1) A window, skylight, or other natural light source forming a part of the enclosure of a dwelling unit shall be constructed, installed, and secured as set forth in subdivision (b)(2) of this section when such window, skylight, or light source is not more than twelve feet above the ground of a street, roadway, yard, court, passageway, corridor, balcony, patio, breezeway or any portion of the building which is available for use by the public or otherwise tenants, or similar area. A window enclosing a private garage, with an interior opening leading directly to a dwelling unit, shall also comply with subdivision (b)(2) of this section.

(2) Window Protection.

(A) Windows shall be constructed so that when the window is locked it cannot be lifted from the frame, and the sliding portion of a window shall be on the inside track. The vertical play shall be taken up to prevent lifting of the movable section to defeat the locking mechanism.

(B) Louvered glass windows shall not be used.

(C) Accessible windows that open should be equipped with secondary locking devices.

(c) Garages. Overhead garage doors shall be provided with a locking device or automatic door opener and shall not have bottom vents except those doors having double louvered or shielded vents or approved alternate devices to protect the locking mechanism.

(d) Keying Requirements. Upon occupancy by the owner each single unit in a tract constructed under the same land use approval plan shall have locks using combinations which are interchange free from locks used in all other separate dwellings.