How to fit an Elro smoke alarm
Updated: 20 October 2026
You have an Elro smoke alarm out of the box and a chair under the landing. How to fit an Elro smoke alarm is three jobs: put it on the ceiling of the escape route, switch that model on the way its battery works, and prove you can hear the test with the bedroom door shut. The mistakes are a kitchen ceiling, a pad on a rough surface, and a 9 V cell left in its wrapper. The [Elro smoke alarm comparison](/hub/fire-protection/elro-smoke-alarm) is where the packs sit. Peter F. used the fire-service pages. This is not a lab fitting. A qualifying purchase can earn a commission at no extra cost to you.
You have an Elro smoke alarm out of the box and a chair under the landing.
You have an Elro smoke alarm out of the box and a chair under the landing. How to fit an Elro smoke alarm is three jobs: put it on the ceiling of the escape route, switch that model on the way its battery works, and prove you can hear the test with the bedroom door shut. The mistakes are a kitchen ceiling, a pad on a rough surface, and a 9 V cell left in its wrapper. The Elro smoke alarm comparison is where the packs sit. Peter F. used the fire-service pages. This is not a lab fitting. A qualifying purchase can earn a commission at no extra cost to you.
Our top picks
| Badge | Product | Mount | How it switches on | Where it goes | Note | Price | Offer |
|---|---|---|---|---|---|---|---|
| Best overall |  ELRO ELRO FS1801 4-pack | Screws, twist-on base | Unwrap and clip the 9 V | Hall or landing ceiling | 7.9 | about £31.15 | View offer |
| Best value |  ELRO ELRO FS1805 2-pack | Magnetic pads | Replaceable cell in the case | Smooth ceiling only | 7.1 | about £16.99 | View offer |
| Alternative |  ELRO ELRO FS4610 | Screws, no magnet kit | Built-in cell, activate on the ring | Ceiling or wall | 6.2 | about £21.99 | View offer |
On this page
Where an Elro smoke alarm goes
Fit it on the ceiling, in the circulation space you would use to get out. For most homes that is the hall and the landing, not above the hob. Scottish Fire and Rescue Service describes about 30 cm of clearance from walls and from light fittings. If you only have one alarm today, put it where smoke from the stair has to pass, then cover the second storey before you cover spare rooms.
These listings are optical smoke alarms. London Fire Brigade wants a heat alarm in the kitchen. Bathrooms are the same problem with steam. Do not paint the case. A battery Elro on the landing is a supplement, not a replacement, if the home already has a mains system. The Elro smoke alarm buying guide matches pack size to storeys.
Screws, magnets and switching it on
The FS1801 fixes with screws. Take the wrapper off the 9 V, clip the connector, and seat the battery so the twist-on base can close. If the base will not twist home, the cell is usually proud of the case.
The FS1805 is sold with magnetic pads. On a smooth ceiling, press the pad and tug it before you trust it over a stair. A rough popcorn ceiling is where one reviewer could not make the pads hold. Check the box for the discs, because one two-pack review said they were missing. The battery split is on the Elro 10 year smoke alarm page.
The FS4610 wakes up differently. The manufacturer page says you can fit it to a ceiling or a wall, you activate it on the ring, and you do not use a magnet kit. The battery is already inside.
Test it, then keep testing
Press the test control on the day you fit it, with bedroom doors closed, and listen from the pillow. Scottish Fire and Rescue Service and Cheshire Fire and Rescue Service both say to test weekly. If you cannot hear it through the closed door, you need another unit on that storey. None of these listings prints a decibel figure.
A short chirp is the low-battery warning, not a fire. On an FS1801 or an FS1805 you replace the cell. On an FS4610 a chirp means the whole unit is due for replacement. A full continuous alarm, when you cannot see a reason, means get out, stay out, and call 999.
When to stop and call someone
Stop when the home needs a mains system. A new dwelling in England is guided, under Approved Document B, towards Grade D2 Category LD3 mains smoke alarms. That is an electrician’s installation, not a magnetic pad. The legal map is on the Elro smoke alarm UK law page. A standard audible Elro, with no stated strobe and no interlink, is a weak plan if someone does not wake to the test. If it sounds and you cannot account for it, get out, stay out, and call 999.
Common questions
Should it go in the hall, on the landing, or in the kitchen?
Hall and landing, on the ceiling of the route you use to escape, with one alarm on each storey. The kitchen needs a heat alarm, which is London Fire Brigade guidance, not one of these optical Elro units. A bathroom is a poor choice because steam sets smoke alarms off. One unit for a whole house leaves the other floors quiet.
How far from a wall or a light?
About 30 cm from walls and from light fittings, which is the clearance Scottish Fire and Rescue Service gives so the alarm is not in still air at the edge of the ceiling. A unit hard against a cornice is worth moving. The FS4610 manufacturer page also allows a wall for that model. Keep clear air around the vents either way.
Can the FS1805 pads replace screws?
On a smooth, clean ceiling, yes. That is how the listing and many reviews describe the fit. Tug the pad before you trust it over a stair. On a rough popcorn ceiling a reviewer could not make them hold, and London Fire Brigade prefers screws to glue. If the discs are missing, do not improvise with tape.
How do you wake an FS1801 versus an FS4610?
On the FS1801, unwrap the 9 V cell, clip it on, and twist the base until it seats. A cell left wrapped will not chirp and will not alarm. On the FS4610 the battery is built in. The manufacturer page says you activate it on the ring. You do not fit a separate cell and you do not add a magnet kit.
How often do you press test?
Weekly, with bedroom doors shut, which is what Scottish Fire and Rescue Service and Cheshire Fire and Rescue Service both ask. The beep on fitting day only starts that habit. If you cannot hear it from the bed, move the alarm or add one. None of these listings states a decibel number you can quote instead.
Related pages
Sources
Public UK sources listed below. Prices, stars and review counts are from amazon.co.uk on 19 October 2026.
- GOV.UK — smoke and carbon monoxide alarms, landlord booklet for England (retrieved 19 October 2026)
- GOV.UK — Approved Document B fire safety frequently asked questions (retrieved 19 October 2026)
- Scottish Government — fire and smoke alarms in Scottish homes (retrieved 19 October 2026)
- GOV.WALES — fitness for human habitation, guidance for tenants and contract-holders (retrieved 19 October 2026)
- Northern Ireland — The Fire Safety Regulations (Northern Ireland) 2024 (retrieved 19 October 2026)
- London Fire Brigade — smoke alarms and heat alarms (retrieved 19 October 2026)
- BSI — BS EN 14604:2005 smoke alarm devices (retrieved 19 October 2026)
- amazon.co.uk listings B08FBDC458, B0B4XLFFFH, B07C8DB4QX, B08CBBY9N8, B0G498FSDY and B07ZRW6SV8 (retrieved 19 October 2026)