Installing an intruder alarm system is one of the smartest investments you can make in protecting your home or business. But even the best alarm kit won’t deliver full protection if it’s installed incorrectly. Unfortunately, many UK homeowners and even some tradespeople make simple mistakes that can undermine security, reduce reliability, or even leave systems vulnerable to tampering.
In this guide, we’ll walk you through the most common mistakes to avoid when fitting an intruder alarm, and show you how to do it right with Ajax security systems and expert resources from WME.
📖 Want to know if Ajax is the right choice for you? Read our full guide: Are Ajax Alarms Any Good?
Mistake 1: Poor Alarm Panel Placement
The alarm panel (or hub) is the brain of the system. One of the biggest mistakes is installing it near the main entrance or in plain sight. If an intruder breaks in, they can attempt to disable it before it alerts you.
✅ Best Practice: Place your control panel in a secure, hidden location but ensure it still has strong signal reach to all sensors.
🔗 See our Burglar Alarm Panels Collection for professional-grade options, our top pick is the Ajax Fibra Hub Intruder Control Panel.
Perfect for both domestic and commercial applications, it ensures a reliable security network capable of protecting your premises from unauthorised access.
Mistake 2: Skipping Key Entry Points
Mistake 3: Ignoring Fire & CO₂ Protection
Mistake 4: Choosing the Wrong Wired vs Wireless Setup
Some property owners assume they need a fully wired alarm system, while others jump straight to wireless. Both have pros and cons:
- Wired alarms – reliable, no batteries, but costly to install.
- Wireless alarms – flexible, easy DIY, but require battery maintenance. (Read our guide on replacing Burglar Alarm batteries for more advice.)
✅ Best Practice: For most homes and small businesses, Ajax wireless systems offer the best balance of security and convenience.
📖 Compare your options: The Complete Guide to Wireless Home Security Systems
Mistake 5: Forgetting the Siren or Bell Box
A visible bell box outside your property is one of the strongest deterrents against burglars. Many installers fit the internal system but forget to mount a clear, visible siren externally.
✅ Best Practice: Always fit a professional alarm box to signal your system is active.
🔗 Browse Burglar Alarm Bell Boxes. WME recommends the Ajax Street Siren Double Deck S, which is designed for optimal security offering a communication range of up to 1,500m.
Mistake 6: Not Setting Up the App Properly
Ajax alarms are designed to be smart, with arm/disarm features, user permissions, and notifications managed through the mobile app. A common mistake is failing to configure these settings properly.
✅ Best Practice:
- Set up multiple users (family, staff, tenants).
- Enable push notifications for tamper or intrusion alerts.
- Regularly update the app and firmware.
📖 Learn how to do this:
Mistake 7: Neglecting Battery Maintenance
Wireless alarms rely on batteries. Forgetting to replace them on time risks leaving your property unprotected.
✅ Best Practice: Check system alerts for low batteries and replace them promptly with high-quality spares.
📖 Step-by-step guide: How to Replace Alarm Batteries
🔗 Shop Burglar Alarm Batteries.
Mistake 8: DIY Without Knowledge of Standards
Some DIY installations cut corners, incorrect sensor placement, non-compliant wiring, or poor siren mounting. This can cause false alarms or even void insurance policies.
✅ Best Practice: Always follow British Standards (BS EN 50131) or hire a professional installer if you’re unsure.
📖 If you want to learn the basics first, read: Guide to Burglar Alarms
Installing an intruder alarm is a smart move, but only if it’s done right. Avoiding these common mistakes ensures your Ajax system performs at its best and keeps your property protected 24/7.
Whether you’re fitting a simple starter kit like the Ajax Hub2 Kit 3 or a full-scale smart alarm system like the Ajax Kit 1 with Keyfobs, WME stocks the full range of Ajax burglar alarms, smoke detectors, and accessories to help you build a robust, compliant setup.