There’s a specific kind of security problem that only exists in share houses — and it’s one that doesn’t get much attention because it doesn’t result in a dramatic break-in. No smashed window. No crowbar on the door frame. No obvious evidence at all. It’s the slow accumulation of uncontrolled key copies and the gradual erosion of basic security habits across a high-turnover household. By the time something actually goes wrong in a Parkside share house, the vulnerability has usually been building for months.
Parkside has a renter rate of around 37.6 percent — above the South Australian average — and its housing stock of converted Victorian and Federation terraces on streets like Sturt Street, Vine Street, and Arthur Street runs to exactly the kind of large, multi-room configurations that become long-term share houses. Many of these properties have been share houses for ten or fifteen years, cycling through successive groups of two to five housemates at a time. The cumulative key situation in some of these properties is genuinely unknown.
This guide is for people in Parkside share houses — whether you’re the long-term tenant managing new housemate arrivals, a new housemate moving into an existing household, or someone whose household is about to change and who wants to understand what that means for their security.
The Key Accumulation Problem
Here’s how the problem develops in a typical Parkside share house over three years.
Year one: Four housemates move in together. The landlord provides four keys — one each. Everyone’s clear on who has what.
Midway through year one: One housemate moves out. Their key is returned. Replacement housemate arrives, uses the existing key. At this point there are still four keys in circulation. Clean.
Year two: Two more housemates move out over the following months. One returns their key. One says they’ve returned it but it’s not in the key box. A replacement housemate cuts their own copy to give to a partner who’s often at the house. Now there are potentially five keys, and the household isn’t sure who has all of them.
Year three: Further turnover. Some keys lost. Some copied. By now the number of people who have — or have had — a key to this property is potentially eight to twelve across the lifecycle of the tenancy, and the number actually in circulation is unknown.
This is not a horror story. It’s a realistic description of key history in a long-running Parkside share house. And it matters because every extra key in circulation beyond the people currently living at the property is a security exposure.
When a Housemate Moves Out: What to Actually Do
The departure of a housemate is the critical security moment in a share house, and most households treat it as purely a practical logistics event — returning the bond, allocating the room to a new person — rather than a security event.
The security action that should accompany every housemate departure is a key reconciliation: all copies of the property key returned, counted, and confirmed. If there is any uncertainty about whether all copies have been returned, or if the departing housemate has had the key for a significant period, rekeying should be considered.
A rekey does not require replacing the entire lock. It requires a licensed locksmith to replace the cylinder — the internal mechanism that the key engages — so that old keys no longer work. The new cylinder comes with a fresh set of keys in whatever number is needed for the new household configuration. In a standard Parkside share house with two external door locks, a rekey typically takes 45 to 60 minutes and costs between $100 and $200 depending on the cylinder type.
When is rekeying warranted rather than just good practice? When a housemate departs on bad terms. When a key is genuinely lost and the departing tenant can’t account for it. When the property has had more than three or four tenancy changes and there’s no clear record of the key situation. When there has been a recent security incident — something taken, a door found unlocked — and the cause is unclear.
When can you reasonably skip it? When the departing housemate has been in the house for a short time, returns their key clearly and directly, and the household has a clean key record. Even then, periodic rekeying — every two or three years in a long-running share house — is worthwhile regardless of specific incidents.
New Housemate Arriving: Questions Worth Asking
If you’re the new person moving into an existing Parkside share house, there are reasonable questions to ask the existing household or the property manager before you commit.
How long has the current household been here, and how many housemates have moved through since the start? This gives you a rough sense of the key history without requiring access to formal records. A household with four occupants, all of whom have been there for two years, has a very different key situation from a household that has turned over six people in the same period.
Has the property been rekeyed in the last two years? A yes with a specific date is the best outcome. An uncertain answer is useful information.
What’s on the rear door? The rear or side door of Parkside terrace properties is almost always the security weak point. If an existing household doesn’t know what hardware is on the rear door, that’s a signal worth following up on.
You’re not interrogating anyone — these are the same questions a responsible property manager should be able to answer. If an existing household finds them strange, that’s partly a reflection of how rarely these conversations happen in share house culture.
Pro Tip: In a share house, agree on a simple written key record at the start of each new household configuration — a note in the group chat or a shared document listing who has what key. When someone leaves, update it. It takes two minutes and creates accountability that prevents the key ambiguity problem from building over time.
Security Habits in a Share House: The Group Dynamic Problem
The practical security habits in a share house tend to default to the least attentive member of the household. If five people live in a house and four of them deadlock the front door every time they leave but one of them routinely pulls it shut without locking — or assumes someone else will lock it — the effective security standard of the household is the one who doesn’t lock.
This is a group dynamic challenge as much as a practical one. The most effective way to address it is to make the security behaviour frictionless: a deadbolt that’s easy to operate, a clear habit established from the start of the tenancy, and a shared understanding that the last person out is responsible for checking both external doors.
Specific friction-reduction measures that help in Parkside share houses:
A key hook immediately inside the door. If the key doesn’t go back on the hook when you come in, you won’t be able to find it when you go out — which means you’re less likely to lock up properly as you leave. A hook is a $3 installation and significantly improves key discipline.
Ensure the deadbolt is operable from the inside without a key. Some older Parkside properties have double-cylinder deadbolts — requiring a key to operate from both sides. In a share house, this is a fire safety issue (you can’t quickly exit in an emergency without finding the key) and it also increases the friction of locking, so people don’t bother. A single-cylinder deadbolt — key outside, thumb-turn inside — is the correct hardware for a shared residential tenancy.
Rear door: Establish a habit, not just a hardware solution. A share house rear door that isn’t deadlocked is often a habit problem as much as a hardware problem. If the rear door leads to a laundry or a shared outdoor area that housemates use regularly during the day, they are not going to deadlock it between every use. A slam lock — which automatically engages the deadbolt when the door closes — solves this; the door is locked every time it shuts, without a key step.
A Call from Arthur Street
I got a call from a Parkside share house on Arthur Street after a camera, a laptop, and some cash had been taken from two separate rooms during a day when all housemates were out. No forced entry — none at all. The rear door showed no signs of damage. The front door was intact.
The household was four people, three of whom had been there for two years. The fourth had moved in six months earlier and replaced someone who’d left the house on reasonably poor terms with the remaining housemates. Nobody had rekeyed when the previous housemate left.
When I examined the rear door, it had a passage latch. No deadbolt. Anyone who had a key to the property — and the household estimated this could include anywhere from two to five previous housemates — could have let themselves in through the front door and out through the unlocked rear without any evidence of a break-in.
We rekeyed the front door, fitted a deadbolt to the rear door, and I advised the household on the slam lock option for future use. A SAPOL report had been filed.
The outcome of the investigation wasn’t shared with me — that’s how it usually works. But the likelihood that an unlocked rear door and an uncertain key history created the opportunity is high.
After the job, one of the longer-term tenants said something that stuck with me: “We kept saying we’d sort the back door. There was just always something else.”
That’s the share house security problem in a sentence.
Strata and Apartment Share Houses
It’s worth noting that some Parkside share houses are apartments rather than standalone terraces — particularly in the blocks along Greenhill Road and near the Unley Road corridor. In an apartment share house, there’s an additional layer: the building entry system.
If the building has a key fob or intercom system for common area entry, the same key accumulation logic applies to building access. Former housemates with unreturned fobs have access to the building even if the apartment itself has been rekeyed. This is a matter for the strata manager or building manager — not something a locksmith can resolve — but it’s worth raising.