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Fire protection compounds for your safety in Bristol & South West areas


Time is of the essence if a fire breaks out at your property. The use of the Rockwool Firestop Compound can give you up to an extra 6 hours of protection from the flames and heat associated with fire – more than enough time in most cases for the fire brigade to arrive. As an approved installer for Rockwool, Fire Immunity can install the most proficient systems at your property in the Bristol and South West.

6 Hours Protection
FREE Consultaion
Load Bearing Capabilities
Replace Existing Compound

How Does Fire Compound Work?


Have you got a concrete slab that has forms of penetration such as electrical wiring or pipework penetrating through? Fire compounding is a fire stopping material substitute that is used to aid fire-rated floors and walls with its sole purpose being, to ensure the integrity of a structure’s compartmentation. 

When installed according to the manufacturer’s specifications, most fire compounds are capable of supporting weight. As a result, it can be installed in restricted areas with light foot traffic.

Replacing Existing Compounds


Over time, fire and building regulations change and it’s important that you keep your safety systems up to date. We can easily drill existing compound systems to allow for additional or replacement provisions to be installed. 

Fire protection compounds are not only cost-effective but also long-lasting, meaning that once installed your fire protection system should be compliant for many years to come. All solutions that we install are suitable for load-bearing situations.

Fire Immunity are one of the leading providers of fire protection compounds in Bristol and the South West

Our Services includes:

Bristol & Surrounding South West Area

    Frequently Asked Questions - Compounding

    UK Fire Regulations require all joints, gaps, and service openings located in walls, floors, or ceilings incorporating a fire-separating element, to be sealed with a fire-stopping material. This material must provide the same fire resistance as the surrounding structure.

    The Rockwool compounding that we recommend is fire tested to BS 476-20 and BS EN1366-3 standards. It is manufactured from non-combustible compounds, including high-quality gypsum cement and graded, lightweight fire-resisting aggregates. Once you add water, the organic binders and gypsum form a mixture that ranges from a stiff mortar to a pourable slurry.

    Any fire-stopping material must provide the same protection from fire and smoke as the surrounding materials. Rockwool compounding material is rated for 4 hours. This means that it will prevent the fire from spreading long enough for the fire brigade to arrive.

    Yes, it is. The Rockwool products that we recommend are capable of supporting up to 2.5Kn. This is suitable for areas with low foot traffic. A 75mm thick slab section of not more than 500 X 500mm in extent, can support its rated weight without reinforcement. If the slab thickness increases to 100mm, then the unreinforced section increases to 750 X 750mm. Larger openings require permanent shuttering, preferably with 50mm Rockwool slab.

    Yes. Once the mortar cures, the compounding provides a waterproof barrier equivalent to the surrounding structure.

    Yes. Fire compound is applied as a 25mm thick plaster that you can trowel into the gaps. After it cures, a pouring-grade mixture is added around pipes and ducting to the height of the screed or as directed by the engineering drawings. It cures in as little as half an hour to 45 minutes. Within 3 days it is sufficiently cured to support limited foot traffic.

    Yes, Rockwool compounding is rated at 40dB at 50mm thickness, 44dB at 100mm thick, and 52dB at 150mm thickness.

    When installed correctly and to the required specification, the fire compound will last the lifetime of the building. The Rockwool compound will not degrade so long as there is no physical damage to the material.

    Yes. Fit adequate permanent or temporary shuttering to support the mortar when applying it to a floor. Remove the shuttering from areas smaller than 750 X 750mm once the mortar cures. Larger gaps require permanent shuttering with an approved, fire-resistant material.

    Yes, fire compound is manufactured from inert materials. One should avoid inhaling the dry powder or getting it in your eyes, so we recommend wearing PPE. Once the compound mixes with water, it cures similarly to cement.