Intumescent Painting of Structural Steelwork

JW Simpkin Ltd delivers professional intumescent painting of structural steelwork for commercial, industrial and residential projects across the UK. Our certified teams apply fire-resistant intumescent coatings to steel structures to achieve required fire resistance periods in line with UK Building Regulations and project specifications.

Intumescent coatings are a critical element of passive fire protection, designed to protect load-bearing steel during a fire by significantly delaying temperature rise and structural failure.

What Is Intumescent Painting?

Intumescent paint is a specialist fire-resistant coating applied to exposed structural steel. In the event of fire, the coating reacts to heat by expanding into a thick, insulating char. This char layer slows heat transfer to the steel, helping maintain structural integrity for 30, 60, 90 or 120 minutes, depending on the system specified.

This method allows architects and designers to maintain exposed steel aesthetics while still meeting fire safety requirements.

On-Site Intumescent Painting

On-site application is carried out once steelwork is installed and prepared. This approach is ideal where programme constraints or design requirements prevent off-site coating.

Benefits include:

• Flexible application on live construction sites

• Suitable for refurbishment and retrofit projects

• Controlled thickness measurements and quality checks

• Minimal disruption to surrounding trades

Off-Site Intumescent Painting (Spray Shop)

Off-site intumescent spraying is completed in a controlled environment before steel is delivered to site.

Benefits include:

• Consistent finish and film thickness

• Faster on-site installation

• Reduced weather and contamination risk

• Improved programme efficiency

Steelwork Preparation and Quality Control

Correct surface preparation is essential for long-term performance. Our process includes:

• Steel surface cleaning and priming

• Compatibility checks between primer and intumescent system

• Accurate dry film thickness (DFT) measurement

• Full installation records and certification

All works are completed in accordance with manufacturer guidance and third-party certification requirements.

Fire Resistance Ratings

We apply intumescent systems to achieve required fire resistance periods, including:

30 Minute Fire Protection

60 Minute Fire Protection

90 Minute Fire Protection

120 Minute Fire Protection

The correct specification is determined by the building type, steel section factor and fire strategy.

Compliance and Certification

Our intumescent painting works comply with relevant UK standards and regulations, including:

• UK Building Regulations

• Approved Document B

• Manufacturer-tested fire protection systems

• Third-party accreditation and inspection

This ensures traceability, accountability and compliance under the Building Safety Act framework.

Sectors We Work In

• Commercial buildings

• Industrial units and warehouses

• Education and healthcare facilities

• Residential and mixed-use developments

• Refurbishment and retrofit projects

Why Choose JW Simpkin Ltd?

• Over 75 years of fire protection experience

• Fully trained and certified applicators

• On-site and off-site capabilities

• Nationwide UK coverage

• Integrated passive fire protection services

Our intumescent painting service integrates seamlessly with our wider passive fire protection offering, including fire stopping, fire boarding, cavity barriers and fire doors.

Intumescent Painting Contractors UK

If you require compliant intumescent painting of structural steelwork, JW Simpkin Ltd provides a reliable, certified solution from specification through to completion.

For more information on Intumescent Paint for a quote call us today on 01332 664700 or make an enquiry using the form below