The Definitive Guide to Certified Fire Rated Mailboxes
PBUK offers a specialised, tested, and certified range of fire-rated Letterboxes and Mailboxes designed to meet the most stringent UK Building Regulations concerning fire containment and means of escape. When installed in common areas, lobbies, or along protected routes, standard mail systems can fatally compromise a wall's fire integrity. Our solutions are engineered to prevent fire spread, protecting both property and lives.
1. The Critical Standard: 120-Minute Fire Integrity
Tested and Certified to BS 476: Part 22
Our flagship range is independently certified by leading testing bodies, such as Exova Warringtonfire, to provide two hours of fire integrity. This is the paramount specification for critical building applications.
Key Applications & Features:
- Maintains Wall Compartmentation: Specifically designed to be recessed into fire-rated walls (e.g., 90-minute or 120-minute walls), ensuring the integrity of the fire compartment is not compromised by the mail slot.
- Protection for Single Escape Routes: Mandatory for installation along the only escape or evacuation route within high-rise residential blocks and commercial buildings.
- Arson and Containment: Proven to withstand and contain an aggressive fire or arson attack originating within the mailbox for up to 120 minutes.
- Robust Construction: Constructed from electro-galvanised steel with a non-combustible powder-coated finish.
Technical Specification Highlights
| Typical Specification |
| External Dimensions (Unit): |
298 mm (W) × 133 mm (H) × 360 mm (D) |
| Mail Slot Aperture: |
240 mm × 40 mm |
| Material: |
Electro-galvanised steel body and door |
| Fire Standard: |
Certified BS 476: Part 22 (120 minute integrity) |
| Installation: |
Recessed, Wall Mounted, or Freestanding Banks |
2. The Non-Combustible Option: Class 0 Rating
Specified for Surface Spread of Flame (BS 476: Parts 6 & 7)
In locations where the fire compartmentation is less critical (e.g., where dual escape routes are available), the priority shifts to ensuring the mailbox itself cannot fuel a fire. This classification is a responsible alternative to the 120-minute rating.
The Class 0 Distinction:
- Inert Materials: The entire assembly is non-combustible; there are no plastics, resins, or similar materials that can ignite or add fuel load in the event of a fire.
- No Fire Contribution: Tested to demonstrate low flame spread, ensuring the mailbox will not be a starting point or contributor to a localised fire.
- Responsible Alternative: A fully compliant and responsible choice for many commercial and residential lobbies where high integrity wall penetration is not the primary concern.
3. Integrated Anti-Arson and Fire Suppression
Protecting Contents with Self-Activating Clean Agent Technology
While our fire-rated mailboxes contain fire, we offer an additional, proactive layer of protection against deliberate arson. This system is a vital anti-arson measure, immediately mitigating risk at the source.
The Suppression System:
- Self-Activating: A flexible, clean agent suppression tube is discreetly installed inside the unit, designed to detect and activate upon sensing rising heat and flames.
- Clean Agent Technology: Uses a safe, non-toxic, and environmentally responsible agent (bromine and chlorine-free) that extinguishes the fire instantly without damaging the surrounding environment or adjacent mail.
- Modular and Retrofittable: The system can be easily fitted on-site by a competent tradesman at the time of mailbox installation.
Why Choose PBUK as Your Fire Safety Specialist?
Our 120-minute and Class O Mailboxes are built on a modular design, allowing us to create Postboxes banks in any configuration (X wide × Y high) to suit your specific architectural requirements.
- Modular Versatility: Create seamless banks for high-capacity apartment buildings or offices.
- Tested Authority: Products certified by recognised UK testing houses, giving you absolute confidence in your specification.
- Expert Compliance Guidance: We understand that every project’s fire risk assessment is unique, affecting product choice, installation, and the competence of the fitter.
Crucial Notice: Shipping and Site Competence
Due to the sensitive nature of the clean agent fire suppression systems, especially concerning international logistics, we cannot guarantee shipment with the agent pre-installed. Furthermore, the final sign-off on the competence of the on-site fitter is a critical regulatory matter.
Contact us today to discuss your project. Our specialist team will ensure you achieve full compliance, advise on the correct fire rating, and confirm the safest, most cost-effective supply solution, including on-site retrofitting of the fire suppression agent.
