Settlement day arrives, the keys change hands, and the list of things to sort out is somewhere between long and infinite. Curtains, internet, that dripping tap, a lawnmower. Fire safety rarely makes the top ten, which is a shame, because it is one of the few items on the list that has a fatality rate attached.

The good news is that it is fast. Here is what to do in the first week, in order.

Find out how old the alarms are

This is the single most useful thing you can do and almost nobody does it. Twist each unit off its ceiling mount and look at the back. There will be a date of manufacture printed there, usually a month and year.

Smoke alarms have a ten year service life from that date. The sensing chamber accumulates dust and household residue and gradually loses sensitivity, which is why the expiry exists and why pressing the test button proves nothing about detection accuracy. If the date is 2016 or earlier, the unit is finished. If there is no date at all, treat it as finished.

In a house that has changed hands a few times, it is very common to find alarms installed by an owner two owners ago. Nobody thought to check, because the test button still beeped.

Count them, and count the gaps

A properly protected New Zealand home has detection in every hallway serving bedrooms, inside each sleeping space, on every level, and in any sleepout, converted garage or cabin someone might sleep in.

Walk it and count. Two storey houses commonly have a single unit downstairs and nothing on the landing. Sleepouts almost never have anything. Neither situation is unusual and both are worth fixing before you unpack the kitchen.

Get the kitchen right

If there is a smoke detector mounted above or very near the hob, it will go off constantly, and within a couple of months somebody will disable it. That is not a character flaw, it is a predictable response to a badly located device.

The correct product for a kitchen is a heat alarm, which responds to rapid temperature rise rather than airborne particles. It ignores steam and toast entirely. Keep the nearest smoke unit at least three metres from the cooking surface and put a heat alarm in the kitchen itself. Same logic applies to laundries and garages.

Understand what applies to you legally

As an owner occupier of an existing house, the honest answer is that nothing compels you to upgrade. The Building Code requirement for interconnected alarms to NZS 4514:2021 applies to new builds and consented renovations from November 2024. The Residential Tenancies Act rules apply to rentals.

Two things to note anyway. First, if your first home came with a minor dwelling you intend to rent out, the tenancy rules do apply to that unit and they are prescriptive. Second, if you are planning consented renovation work, which a lot of first home buyers are, the interconnection requirement will apply to that work and it is much cheaper to plan for than to add late.

What to buy

• Photoelectric sensing. Detects the slow smouldering fires that occur at night far earlier than older ionisation technology.

• Sealed ten year lithium battery. No annual battery change, no three in the morning chirping, and nobody can borrow the battery.

• Interconnection, wireless if you do not want to rewire. Particularly valuable in two storey homes and properties with detached sleepouts, because one detection sounds every alarm at once.

• A hush function, so a genuine nuisance activation can be silenced briefly without disabling anything.

Products from CAVIUS, Watchman and SmartSense are distributed in New Zealand by On Point Distribution and stocked at more than 700 retailers and electrical wholesalers nationwide. If you are working out what a modern smoke alarm nz should include before you spend anything, comparing a specialist range is a better starting point than a hardware aisle.

Then do the boring bit

Walk the two exits from every bedroom. Agree a meeting point at the letterbox or a specific tree. Say it out loud to whoever lives with you. It takes ten minutes and it is the part of fire safety that costs nothing.

Buying a first home in New Zealand is expensive and exhausting and full of compromises. Working detection in the right rooms is one of the few items on the list that is cheap, fast, and genuinely consequential. Do it in week one, before the list gets away from you.