Yes, every exterior door that swings on hinges should have its own deadbolt, not just a spring-latch knob or lever lock. Here’s the reasoning, plus the two situations where the hardware works a little differently.
Why a Knob Lock Alone Isn’t Enough
A standard knob or lever lock uses a spring latch with a small, angled bolt, designed for convenience, not resistance. It can often be forced with a firm kick or even slipped with a thin card. A deadbolt’s bolt is a solid, squared-off throw that extends deep into the frame, which is what actually resists forced entry.
Front Door
This one’s obvious, and usually already has a deadbolt. Make sure it’s Grade 1 or 2 and properly installed with a reinforced strike plate.
Back and Side Doors (The Ones People Skip)
We routinely find older homes, especially around South Pasadena and Pasadena, where the back door only has a basic knob lock, because it was treated as a lower priority than the front. Burglars know this too; see our post on how burglars choose easy targets. Back and side doors need the same deadbolt standard as the front.
Garage Man-Doors and Side Gates
The pedestrian door from a garage into the house, and any side gate leading to a backyard, are commonly overlooked entry points. Both should have a deadbolt-grade lock, not just a standard latch.
The Egress Exception
Any deadbolt on a required emergency escape door must be openable from the inside without a key, a single-cylinder deadbolt with a thumbturn, not a double-cylinder key-both-sides deadbolt. This is a California fire-code requirement, not a suggestion.
The Sliding Door Exception
Sliding glass doors don’t use a traditional deadbolt mechanism, they typically need a supplemental foot bolt, pin lock, or bar lock in addition to the factory latch, since the standard latch alone is easy to force or lift off track.
What It Typically Costs to Add Deadbolts to Every Door
In the LA area, adding or upgrading a deadbolt per door typically runs in a modest, predictable range including labor and hardware, and it’s one of the highest-value security upgrades per dollar spent. See our Safes & Deadbolts service for details.
Not sure which of your doors are missing proper hardware? We’ll check every entry point on the visit. Call 818-249-5128.