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Fire Safety

Fire Stopping

Fire stopping that seals the breaches in your building’s fire-resisting walls and floors, installed to certified systems that actually perform.

Fire stopping is the work that seals the gaps, joints and service penetrations passing through a building’s fire-resisting walls and floors. Every cable, pipe and duct that crosses a compartment line is a potential route for fire and smoke unless it is correctly sealed. MAST Safety carries out fire stopping for building owners, managing agents, landlords and employers, restoring the integrity of your compartmentation so the barriers in your building perform as they are meant to.

Why correct fire stopping matters

A compartment is only as good as its weakest point. One unsealed penetration around a cable tray or a poorly filled gap at the head of a wall can let fire and smoke pass between compartments and defeat the whole strategy. Just as important, fire stopping only works if it is installed correctly. The wrong product, or the right product fitted in the wrong way, can look finished while providing little or no protection.

Your legal duty

The responsible person has a duty under the Regulatory Reform (Fire Safety) Order 2005 to maintain the building’s fire precautions, and properly installed fire stopping is a core part of that.

We can work from our own compartmentation survey or from a survey or fire risk assessment you already have, so you can come to us purely to get the sealing done. Where breaches are found, we put them right, giving you a single provider from the first finding to a sealed, evidenced compartment.

Breaches flagged in a survey or assessment?

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What our fire stopping covers

MAST Safety provides professional fire stopping surveys. The primary purpose of this service is to assess the condition, and suitability of passive fire protection measures. The survey will focus on the service penetrations, and typically construction joints to assess, and verify that the fire stopping systems will perform as intended. The surveys are predominantly visual and sampling-based, unless intrusive works are requested and commissioned.

Improperly sealed openings can allow smoke and fire to spread rapidly through a building. Our fire stopping works help restore and maintain the integrity of passive fire protection systems using tested and compliant materials.

Our fire stopping services include:

  • Sealing service penetrations
  • Fire-rated mastic and sealant application
  • Batt and coating systems
  • Pipe collars and wraps
  • Cable penetration sealing
  • Remedial fire stopping works following surveys

Installed to tested, certified systems

Fire stopping performs only when it matches a system that has been tested and certified for that exact situation, the right product for the substrate, the service passing through it and the fire rating required. We install to manufacturers’ tested details rather than reaching for a generic filler, so what goes in is what was actually proven to work. That is the difference between fire stopping that looks done and fire stopping that will hold when it is needed.

From survey to sealed, one provider

Because we also carry out compartmentation surveys, you can move from identifying breaches to sealing them without sourcing a separate contractor, keeping the work moving and the accountability in one place. Fire stopping also follows on naturally from a Fire Risk Assessment and sits alongside our fire door remedial works as part of your building’s passive fire protection. You can see how we combine these into one coordinated programme in our residential portfolio case study.

Evidence of every seal

We record the fire stopping we install, capturing the location, the system used and supporting photographs, so you have a clear record of the work. That gives you the evidence to show your compartmentation has been restored, and a record that becomes increasingly important for higher-risk buildings where the history of fire safety work needs to be demonstrable.

Restore your compartmentation

Tell us what your survey or fire risk assessment has flagged, or ask us to survey it first, and we will seal the breaches with the correct certified systems and as little disruption to your building as possible. From a single penetration to a whole portfolio, you deal with one team from the finding to the sealed compartment. Call us, send a message or drop us an email, and we will come back to you, usually the same working day.

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Fire Stopping FAQs

What is fire stopping?
Fire stopping is the sealing of gaps, joints and service penetrations through fire-resisting walls and floors, using tested fire-resisting materials and systems. Its job is to maintain the integrity of a building's fire compartments so fire and smoke cannot pass between them.
Why does fire stopping need a competent installer?
Because it only works if it matches a tested, certified system and is installed correctly. The wrong product, or the right one fitted badly, can appear finished while offering little protection, so competence and the use of certified systems are what make the difference.
Can you carry out fire stopping from a survey we already have?
Yes. We can work from a compartmentation survey or fire risk assessment produced by someone else, as well as from our own surveys, so you can come to us purely for the sealing work if that suits you.
Will the work restore our building's compliance?
The aim of every job is to restore the fire resistance of the compartment line in line with current requirements, using certified systems, and we record what was done so you have the evidence to show it.
Do you provide documentation of the work?
Yes. We record each installation, including its location, the system used and supporting photographs, giving you a clear record of the fire stopping carried out across your building.
Do you work on single buildings or whole portfolios?
Both. We handle individual remediation jobs as readily as coordinated fire stopping programmes across a managed portfolio.

What clients say

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“Excellent training and great venue The trainer was absolutely excellent—knowledgeable, engaging, and genuinely funny, which made what could’ve been a grueling week much more enjoyable. The venue was also very comfortable and well-equipped, adding to the overall positive experience.”

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“Mast Safety – An Outstanding Experience! I recently completed a course with Mast Safety, and I can honestly say it was an excellent experience from start to finish. The training was not only comprehensive and engaging, but the hands-on approach made everything so much easier to understand. A special shout-out to Mark, who was an incredible tutor. His knowledge of safety protocols was impressive, and his ability to explain complex topics in an easy-to-understand way made the whole learning process enjoyable. He was patient, approachable, and always made sure to address any questions we had. His teaching style was interactive and motivating, which made the course feel less like a lesson and more like a conversation. If you're looking to enhance your safety training, I highly recommend Mast Safety. It's clear that they care about providing quality education and Mark is a perfect example of what makes this company stand out. Highly recommended! Paul C”

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“A truly exceptional trainer Mark’s training course was nothing short of transformative. With nearly 30 years in the railway industry, I’ve never enjoyed a course—until now. Mark’s unassuming and approachable nature made everyone, from graduates to veterans, feel comfortable and valued. His ability to connect, remember names, and craft an interactive five-day session was truly special. It didn’t even feel like training! Mark owns a rare, natural talent that can’t be taught, and the experience was outstanding from start to finish. If you’re considering training, I wholeheartedly recommend this company—and if you’re lucky enough to get Mark, you’re in for something exceptional. Thanks, Mark, and best of luck! Ps If you get the Bert and Ernie question, probably best not to answer Sack him.”

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Let's make compliance one less thing to worry about.

Speak to a MAST advisor about consultancy, retained support or fire safety. Free initial call, clear pricing, no obligation.

020 3225 3078WhatsApp(opens in a new tab) info@mastsafety.co.uk

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