Window and Door Restrictors are small yet crucial safety components designed to enhance home and business security. These devices limit how far a window or door can open, helping to prevent accidents and falls while maintaining ventilation. Perfect for keeping your home cool during warmer months.
For UK homeowners, understanding how and when to install restrictors is essential. Not just for safety and comfort, but also for compliance with UK building regulations. This comprehensive guide explains everything you need to know about window restrictors, door restrictors, and legal requirements, helping you choose the right solutions for your property.
What Are Window and Door Restrictors?
A window or door restrictor controls the maximum opening distance of a window or door. It provides an additional layer of security and prevents accidents, especially in homes with children, elderly residents, or pets. Restrictors come in various designs suitable for casement windows, sash windows, French doors, sliding patio doors, and bifold doors.
French Doors vs. Patio Doors: What’s the Difference?
Before choosing a restrictor, it’s important to understand which type of door you have, as each requires different hardware.
French Doors
French doors are hinged doors featuring multiple small glass panes divided by glazing bars. Their timeless, elegant design complements both period properties and modern homes seeking a traditional aesthetic. Typically, both doors open outward or inward, allowing wide access and a touch of grandeur.
Patio Doors
Patio doors usually refer to sliding or bifold doors. Sliding patio doors open horizontally along a track instead of swinging open, making them ideal for modern spaces where saving room is key. These doors maximise natural light with large glass panels and slim frames, creating a sleek, contemporary look.
Why This Matters for Restrictors
• French doors need restrictors compatible with hinged mechanisms.
• Sliding doors require restrictors that integrate with the track system.
• Bifold doors demand flexible restrictors that maintain functionality while enhancing safety.
Always consider the door’s weight, size, and movement pattern when choosing your restrictor.
UK Legal Requirements and Building Regulations
Installing restrictors isn’t just about safety — in many cases, it’s a legal requirement under UK building regulations.
When Are Window Restrictors Legally Required?
Restrictors must be installed in buildings accessible to at-risk individuals — such as children, patients, or residents in care environments. This includes:
• Schools and nurseries
• Hospitals and care homes
• High-rise residential buildings
Restrictors limit window openings to 100mm (10cm) or less, preventing falls while still allowing ventilation.
The 100mm Safety Standard
Under BS EN 13126-5:2011 + A1:2014, windows must not open wider than 100mm (typically 89mm in practice) to prevent a small child from passing through. This standard ensures a balance between safety and airflow, maintaining adequate ventilation while reducing fall risks.
Relevant Building Regulations
When installing restrictors, ensure compliance with:
• Part K – Protection from falling, collision, and impact
• Part B – Fire safety and escape routes
• Part F – Ventilation and air quality
• Part L – Energy efficiency and insulation
Choosing the Right Restrictors for Your Windows and Doors
Window Restrictors
Casement Windows
The most popular option is the cable restrictor, which allows limited opening for ventilation but can be released fully for cleaning or emergencies.
Sliding Windows
Use track stops or sliding locks that restrict horizontal movement, ensuring windows can’t be opened beyond a safe distance.
Sash Windows
Traditional sash windows require specialist restrictors that maintain the window’s vertical operation and heritage design.
Door Restrictors
French Doors
Best restrictor options include:
• Door chains with integrated safety catches
• Hinged restrictors that limit the swing angle
• Cable restrictors designed for glass-heavy doors
These devices must be strong enough to handle the weight and force of the door while preventing over-extension.
Sliding Patio Doors
Ideal restrictor choices:
• Track stops to prevent over-sliding
• Locking restrictors with adjustable opening widths
• Ventilation locks for partial openings
These allow airflow and visibility while maintaining home security.
Bifold Doors
Use specialist bifold restrictors that protect the folding system without compromising flexibility or ease of use.
Safety by Room: Tailoring Restrictors to Your Space
• Children’s Bedrooms: Use permanent restrictors that cannot be removed without tools.
• Living Rooms & Common Areas: Choose removable restrictors that offer easy cleaning access and emergency escape routes.
• Upper Floors: Always install restrictors to prevent fall risks.
Permanent vs. Non-Permanent Restrictors
Permanent Restrictors
• Pros: Tamper-proof, ideal for child safety, highly durable
• Cons: Harder to clean windows, may impact emergency egress
Non-Permanent Restrictors
• Pros: Easy to remove for cleaning or escape, budget-friendly
• Cons: Can be disabled accidentally or intentionally by older children
A hybrid approach works best, use permanent restrictors in high-risk zones and removable ones in communal areas.
Balancing Child Safety and Fire Safety
Every home must balance child safety with fire escape needs. Choose restrictors that feature:
• Quick-release mechanisms for emergencies
• Key-operated releases for adult-only access
• Accessible controls for those with limited mobility
Ensure all family members know how to operate restrictors in an emergency.
Installation and Maintenance
Most restrictors are DIY-friendly, but precision is key. Always:
• Follow manufacturer instructions carefully
• Use correct fixings for your window or door material
• Test the restrictor before final installation
Professional Installation
For complex systems — especially in schools, care facilities, or commercial properties. Professional installation ensures compliance and long-term reliability.
Ongoing Maintenance
Regularly inspect restrictors for wear and tear, ensure mechanisms function correctly, and replace any damaged components to maintain compliance with safety standards.
How to Choose Quality Restrictors
When shopping for restrictors, always look for:
• CE marking and British Standard (BS EN) certification
• Durable materials such as stainless steel or reinforced plastic
• Corrosion resistance for outdoor applications
• Ease of operation for all users
Shop Window and Door Restrictors at FixTrade.co.uk
At FixTrade.co.uk you’ll find a wide selection of window restrictors and door restrictors designed for every UK home. From modern apartments to traditional properties.
Whether you’re focused on child safety, building regulation compliance, or ventilation, FixTrade.co.uk offers affordable, high-quality solutions that combine protection with convenience.
Browse our full range of window and door restrictors today to make your home safer, more secure, and regulation-compliant.