Deadbolt vs Knob Lock: Which Lock Type Should You Install on Your Perth Home?
- •Deadbolts offer significantly stronger forced-entry resistance than knob locks.
- •Knob locks alone on exterior doors are a security risk — a screwdriver can defeat them.
- •The best Perth homes use deadbolts on all exterior doors and knob locks on interior rooms.
- •A licensed locksmith ensures correct installation — a poorly fitted deadbolt can be as weak as no lock at all.
- •Rekeying after moving in is just as important as which lock type you choose.
You’re standing at a hardware store staring at rows of locks, or you’ve just been quoted on a lock installation and you’re wondering: does it actually matter which type you choose? It absolutely does — and picking the wrong lock for the wrong door is one of the most common security mistakes Perth homeowners make.
What Is the Difference Between a Deadbolt and a Knob Lock?
Understanding the mechanical difference that separates a secure door from an easy target.
A knob lock has its locking mechanism built inside the knob itself. The locking cylinder sits exposed, which means it can be snapped, gripped, or forced with basic tools. On an exterior door, this is a serious vulnerability.
A deadbolt works differently. When you turn the key or thumb-turn, a solid steel bolt extends directly into the door jamb and strike plate — there’s no spring mechanism to push back. That means kicking or forcing the door requires overcoming the full strength of the bolt, the strike plate, and the timber frame itself.
Basic knob locks can be defeated with a screwdriver and brute force in seconds. A properly installed deadbolt with a reinforced strike plate makes forced entry dramatically harder — enough to deter most opportunistic break-ins entirely.
Where Should You Use a Deadbolt vs a Knob Lock?
The right lock in the right place makes all the difference to your home's real-world security.
Exterior doors — your front door, back door, and garage entry — should always have a deadbolt as the primary lock. A knob lock on these doors alone is not adequate security for a Perth home.
Interior doors — bedrooms, bathrooms, and home offices — are well-suited to knob locks or lever handles, where privacy rather than high security is the goal. You don’t need a deadbolt on every internal door in your house.
- •Front door: deadbolt — non-negotiable for exterior security
- •Back and side entry doors: deadbolt — often the target of opportunistic entry
- •Sliding doors: specialist locks or security bars — standard deadbolts don't suit the frame
- •Bedrooms and bathrooms: knob lock or lever handle with a simple privacy latch
- •Home office or study: consider a deadbolt if you store valuables inside
Are Single or Double Cylinder Deadbolts Better for Perth Homes?
Cylinder choice affects both security and emergency egress — know the trade-off before you decide.
A single cylinder deadbolt uses a key outside and a thumb-turn inside. It’s the most common residential choice because you can exit quickly in an emergency without needing a key.
A double cylinder deadbolt requires a key on both sides. This is useful if there’s glass near the lock — a burglar can’t simply break the glass and reach in to turn a thumb-turn. The trade-off is that in a fire or emergency, you need your key to exit. If you choose double cylinder, always keep a key nearby but out of sight from the door glass.
If your front door has a sidelight or glass panel within arm’s reach of the lock, a double cylinder deadbolt is worth considering. Discuss the egress implications with your locksmith before installing.
Does Lock Installation Quality Matter as Much as Lock Type?
Even the best deadbolt is only as strong as the installation behind it.
Yes — significantly. A deadbolt fitted with a flimsy strike plate and short screws can be kicked in almost as easily as a knob lock. The strike plate needs to be secured with long screws that reach into the wall stud, not just the door jamb timber.
This is one reason why professional lock installation matters. A licensed locksmith assesses the door frame, aligns the bolt precisely, and fits a reinforced strike plate — steps that a rushed DIY job often skips. If you’re weighing up whether to do it yourself, the related article Can You Install Your Own Locks? DIY vs Hiring a Perth Locksmith Explained covers the risks in detail.
If you’re not sure whether your current locks are up to standard, the article Top 5 Signs Your Perth Home Needs New Locks Installed Right Away is a practical starting point for assessing what you have.
Your Deadbolt and Knob Lock Questions Answered
Straight answers to the questions Perth homeowners ask most about lock types and installation.
Can I Use a Knob Lock as My Only Lock on a Front Door?
It’s not recommended. A knob lock on an exterior door without a deadbolt above it is a significant security gap — the locking cylinder is exposed and can be forced quickly with basic tools. For any exterior door, a deadbolt should be your primary security lock.
How Much Does Deadbolt Installation Cost in Perth?
Costs vary depending on the lock grade, brand, and whether new boring is required in the door. For a detailed breakdown, the related article How Much Does Lock Installation Cost in Perth? A Honest Price Breakdown covers typical price ranges. For a specific quote, calling a local licensed locksmith is always the most accurate approach.
Should I Rekey or Replace Locks When I Move Into a Perth Home?
Rekeying is usually sufficient if the existing locks are in good condition — it changes the internal pin configuration so old keys no longer work, at a lower cost than full replacement. If the locks are worn, outdated, or you’re upgrading to deadbolts, replacement makes more sense. Either way, doing one or the other when you move in is essential.
What Grade of Deadbolt Should I Buy for a Perth Home?
Lock grades are assessed on durability and security resistance. For residential use, a quality mid-to-high grade deadbolt from a reputable brand is appropriate for most Perth homes. Your locksmith can recommend a suitable product based on your door type and security needs — it’s worth getting their advice before purchasing, as not all deadbolts suit all door frames.
Ready to Upgrade Your Perth Home's Locks?
Whether you need a deadbolt installed, existing locks assessed, or a full security upgrade, Ultimate Lock is available 24/7 across Perth. Call 0481 365 802 now or request a quote and we’ll get back to you fast.
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Part of our guide: The Complete Guide to Lock Installation for Perth Homes and Businesses