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Waterfront Business Centre 57A
North Woolwich Road London E16 2AA UK
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Ph: +44 (0) 2070550566

Linear Gap Sealing READ MORE

London's leading and independent specialist passive fire protection contractor

SIV Fire Protection is providing expertise in all types of Built-in fire protection and passive fire protection solutions.

Linear gap sealing

In a fire, four hours is a long time. And that’s how long linear gap sealing can buy you. Time to get out and get the professionals in.

If you’ve got gaps between door frames and compartment walls or between compartment walls and the ceiling (or any other gaps), you need linear gap sealing.

The size of the cavity dictates our approach:


Intumescent sealing

Intumescent sealing is good for gaps up to 30mm. That’s a small opening, but fire and smoke get everywhere. If you’ve got imperfect fits and small void gaps in your head of wall and ceilings, fire and smoke will spread fast.


We’ll use acoustic intumescent sealant to seal those joints and void gaps. To ensure you’re properly protected for up to four vital hours.


  • Tested to BS EN 1366-3 and BS EN 1366-4 for peace of mind
  • Stops smoke in its tracks, saves lives
  • Fast to apply and cure
  • Works on many substrates and services
  • Available in several colours.


Typical applications

  • Head of wall
  • Compartment walls
  • Vertical and horizontal joins between different fire compartments
  • Around fire-rated door frame and wall
  • Between lift door frame and shaft wall.


Ablative coated batt and intumescent sealing

Large service openings can leave your building vulnerable to the spread of fire and smoke. With an ablative coated batt, you’ll get an air-seal barrier. It’s a mineral wool-insulation product with a high-performance ablative coating.


We can install it across walls, floors and seals, plus large-framed gap voids. You’ll get a critical four-hour window of fire-stopping. As a bonus, you’ll enjoy improved acoustics and less air leakage, so your building maintains its heat.


  • Fast to install – little disruption
  • Reliable and long-lasting – no further disruption
  • Tested for airtightness – dependable
  • Made from renewable resources – environmental.
  • Typical applications


Typical applications

  • Intumescent ceilings
  • Larger gaps at head of fire-rated walls
  • Fire-stopped ceilings
  • Fire-rated door frames.

Movement joint soft seals

If movement is built into your building design, we can install movement joint soft seals. These create linear joint and penetration seals. Made from low-density stone wool, they’ll reinstate fire resistance, acoustic and air-seal performances in floors, walls and dry-wall systems that have large gaps.

The seal is a special foam laminated with intumescent layered on both sides. It’s designed for rigid walls and ceilings. Its beauty lies in its flexibility: it expands when exposed to heat.


  • Tested to EN 1366-4 + A1: 2010 E 120, EI 120 and BS476 for peace of mind
  • Stops fire for up to two hours
  • Good acoustic isolation
  • Air-permeability tested
  • Tested with cable trunking
  • Resists vermin
  • No maintenance required.

Typical applications

  • Soft joints.

Fire Stopping

SIV's Fire Stopping Solutions

Operating nationally from our office in London, we offer our clients a complete integrated Linear Gap Sealing package from pre-tender support right through to installation, commissioning and project handover.

Quality, Innovation and Sustainable

SIV's Passion

SIV Fire Protection are approved installers for a number of market leading system manufacturers working only with reliable suppliers that share our passion for quality, innovation and sustainable business practices.

Business Practice

SIV’s Business Practice

Working to the highest possible SHEQ standards, SIV’s business practice is defined by its unwavering passion for its clients and its critical, insider knowledge in every aspect of the field.

Working Environment

SIV Company Values

It is our firm belief that adherence and demonstration of our Company Values will build up a more positive and efficient working environment and benefit our clients, key suppliers and all those who interact with the Company

SIV Fire Protection

Awards &

In The Field Of Exceptional Innovative Marketing…SIV Sets New Standards and Stands Apart


Want to know more about us?

Ph: +44 (0) 2070550566


Waterfront Business Centre
57A North Woolwich Road
London E16 2AA

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Need a fire stopping solution offering quality without compromise? Want to talk over your options?

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