Protherm Light is a lightweight cementitious spray-applied fire protection system for structural steel and concrete. It provides passive fire protection across commercial, industrial, infrastructure and high-rise buildings in the UK.

It is typically specified for steel beams, columns, composite slabs and reinforced concrete where A1 non-combustible, mineral-based fire protection is required.

Density
Approximately 300 kg/m³

Durability classification
Z2 (EAD 350140-00-1106)

Thermal conductivity
(λD): 0.079 W/mK

Application method
Mechanical spray

Fire resistance
R30 to R240 (subject to thickness and section factor)

Reaction to fire
A1 EN (13501-1)

CE marked
under Regulation (EU) 305/2011

Fire Performance

Structural Fire Resistance for Steel and Concrete

Protherm Light is a cementitious spray fire protection system assessed for use on structural steel and concrete in accordance with the EN 13381 series. It delivers declared structural fire resistance from R30 to R240, depending on applied thickness and steel section factor.

As a passive fire protection system for structural steel, performance is classified in accordance with EN 13501-2, where the “R” classification refers to the ability of a loadbearing element to maintain structural capacity during fire exposure.

Declared fire resistance ratings (subject to thickness calculation):

R30 – 30 minutes loadbearing capacity
R45 – 45 minutes loadbearing capacity
R60 – 60 minutes loadbearing capacity
R120 – 120 minutes loadbearing capacity
R180 – 180 minutes loadbearing capacity
R240 – 240 minutes loadbearing capacity

This range enables specification across commercial, high-rise, industrial and infrastructure projects requiring certified spray-applied fire protection in the UK.

Assessment Standards and Certification

Fire performance is supported by assessment under:

EN 13381-1 – Horizontal loadbearing membranes
EN 13381-3 – Concrete members
EN 13381-4 – Steel members
EN 13381-5 – Composite steel and concrete members

Supporting documentation includes:

European Technical Assessment ETA 18-1111
Declaration of Performance (Regulation EU 305/2011) n. EDI10/2022

These documents provide the technical basis for specification of spray fire protection systems within UK building regulations and project compliance frameworks.

Determining Required Fire Protection Thickness

Required thickness for structural steel fire protection is determined using the section factor (Hp/A), representing the ratio between heated perimeter and cross-sectional area of the steel member.

Higher Hp/A values require increased cementitious spray thickness to achieve the required fire resistance period. Final design thickness must always be derived from the approved EN 13381 assessment tables and ETA documentation.

Featured

Feb 26, 2026

Construction Products Reform White Paper – What It Means for the Industry

Feb 26, 2026

The Construction Products Reform White Paper marks a significant shift in how construction products are assessed and regulated across the UK.

While it does not rewrite combustibility classifications, it raises the evidential and accountability bar for manufacturers, specifiers and the wider supply chain.

This article explains what is changing, what it means in practice, and how system-led compliance will shape the next phase of construction regulation.

Feb 26, 2026

Mechanical and Physical Properties

Protherm Light combines lightweight composition with mechanical robustness, providing stable, durable cementitious spray fire protection once cured.

Density
Approximately 300 kg/m³. This significantly lower density compared to traditional heavyweight cementitious fire protection reduces additional dead load on the structure while maintaining effective passive fire performance.

Thermal Conductivity
λD = 0.079 W/mK. The low thermal conductivity helps slow heat transfer to the protected steel or concrete substrate, supporting extended structural fire resistance during fire exposure.

Compressive Strength
0.97 N/mm². Provides adequate mechanical robustness once cured, supporting durability during service life and resistance to incidental site impact.

Flexural Strength
0.35 N/mm². Contributes to resistance against minor cracking, vibration and structural movement.

Adhesion Performance
Adhesion values demonstrate effective bond to both steel and concrete substrates when correctly prepared and applied:

Concrete (50 mm): 0.3 N/mm²
Concrete (9 mm): 0.24 N/mm²
Steel (60 mm): 0.15 N/mm²
Steel (10 mm): 0.05 N/mm²

Reliable adhesion is critical to ensure cementitious spray fire protection remains securely in place during service conditions and under fire exposure.

Durability Classification
Category Z2 in accordance with EAD 350140-00-1106. This classification should be read alongside the Declaration of Suitability for External Use, confirming performance under defined exposure conditions and supporting specification in both internal and certain externally exposed environments.

External Use

Protherm Light is declared suitable for use in externally exposed environments when installed, cured and detailed in accordance with manufacturer instructions.

The Z2 durability classification referenced within ETA 18-1111 relates to defined exposure conditions under EAD 350140-00-1106. This classification does not prohibit external application and should be read alongside the Declaration of Suitability for External Use, which confirms intended performance under specified environmental conditions.

When correctly specified and applied, Protherm Light can be used in projects where structural elements are subject to intermittent or ongoing exposure to external climatic conditions.

Typical applications include:

Open or partially enclosed car parks
Structural steel exposed during phased renovation or refurbishment works
Airport canopies and public transport shelters
Infrastructure and industrial structures with partial weather exposure

Passive Fire Protection of a Steel Structure in Pieve di Cadore - Before

Passive Fire Protection of a Steel Structure in Pieve di Cadore - After

Insurance-Backed Manufacturer Warranty

Protherm Light is supported by a manufacturer-issued, insurance-backed warranty that can be provided in favour of the building owner, subject to project registration and installation in accordance with approved manufacturer requirements.

This warranty structure provides an additional layer of commercial protection beyond standard contractor liability, helping to reduce risk for developers, principal contractors and asset owners.

Key benefits include:

Protection extending beyond installer warranties
Reduced financial exposure for developers and building owners
Security in the event of installer insolvency (subject to policy terms and conditions)
Alignment with approved materials, assessment data and defined application methodology

By combining certified spray fire protection performance with insurance-backed manufacturer support, Protherm Light provides both technical and commercial reassurance for UK construction projects.

Full terms and conditions are detailed within the Declaration of Suitability for External Use.

Application and Installation

Protherm Light is applied by mechanical spray using approved plastering equipment such as PFT G4, G5 or equivalent. Correct installation and thickness control are essential to achieve declared structural fire resistance in accordance with EN 13381 and ETA 18-1111.

Installation Parameters

Ambient and substrate temperatures between +5°C and +35°C
Maximum single coat thickness of 20 mm
Multi-coat application where required thickness exceeds 20 mm
Continuous, uniform coverage to calculated design thickness
Proper substrate preparation to ensure declared adhesion performance

Material Consumption

Approximately 3.0 kg per m² per 10 mm of applied thickness.

Packaging

18 kg bags
44 bags per pallet

Typical UK Applications

Protherm Light is specified across the UK for:

Structural steel fire upgrading
Refurbishment and remediation works
Composite slab protection
Reinforced concrete structures
High-rise and commercial developments

Commercial Buildings

Public Sector Buildings

Offices, hotels, retail developments and mixed-use buildings.

Hospitals, schools, fire stations and civic buildings.

Factories, warehouses, logistics and manufacturing facilities.

Apartments, housing developments and multi-storey residential structures.

Residential Buildings

Industrial Buildings

Car Parks and Infrastructure

Open car parks, transport structures and infrastructure projects.

These examples illustrate common applications but do not represent the full range of potential uses.

For further technical information on Protherm Light, including fire resistance design guidance, project support or specification advice, please contact the Ramco Industries UK technical team.

We can assist with:

Fire protection thickness guidance based on section factor
Product documentation and certification
Project specification support
Integration with Ramco mineral board systems including Hilux and Hicem

Please use the contact form provided to submit your enquiry and a member of our technical team will respond.

Ramco Industries UK supplies a range of mineral-based fire protection and building board systems for commercial, industrial and infrastructure projects across the UK.