Intumescent coating systems to protect structural steel from a fire or extreme heat are advantageous for many reasons. They are fast and clean to apply, have a paint-like appearance and can be finished in a full range of topcoat colours. Perhaps the biggest benefit is their durability, meaning once they are installed they are virtually maintenance-free.

When intumescent coatings are applied in line with the manufactures’ guidelines it is generally accepted that it will provide fire protection for the lifespan of the building. However, inspections and product maintenance are still important, as damage to intumescent systems can occur through excessive impact during installation or after the building has been completed.


Regular inspections of passive fire protection systems are generally managed by the building manager. Inspection intervals are generally stated in the specification as will depend on a number of factors including:

  • The products used and manufacturers recommendations.
  • The location of the steelwork (e.g. above a ceiling).
  • The type of building and building use (e.g. a warehouse exposes the steelwork to the high potential for physical damage).
  • Environmental considerations (e.g. a highly corrosive environment such as high humidity and temperatures in swimming pools).

As a general guideline, inspections should be scheduled every two years as part of the buildings general maintenance regime.


Minor damage, such as chips and scrapes, will not usually affect the fire protection performance of an intumescent coating system unless the environment is wet or exposed to the elements. If exposed to water, for example, the damaged area may allow moisture to seep within the intumescent layers leading to degradation of the coating over time.

The amount of damage permissible before performance is impaired is determined by the fire testing conducted by the manufacturer. Damaged areas of ≥150mm2 are deemed to be substantial and should be immediately repaired. However, any obvious damage should always be assessed by a passive fire protection professional.

Maintenance and Repairs

In the case of damaged intumescent systems due to water absorption, impact damage or voluntary removal, maintenance interventions will be required. A certified passive fire protection specialist who understands the importance of restoring the intumescent and topcoats layers to create the overall system will be required. It is important that only a certified specialist touchup intumescent systems as a buildup of top cots could be detrimental to the overall system. For example, a guide set by manufacturer Promat, allows the paint to be applied at 30 microns DFT per coat, with a total thickness of the system not exceeding 90 microns.

Repairing intumescent damaged during transport

The application of intumescent coating systems offsite enables streamlined construction, reduces overall project costs and better quality control. One concern builders often have is the potential for damage to the coated beams during transport. ProFinish always ensures beams are moved with padded slings rather than chains to reduce the risk of damage. If damage does occur, the ProFinish team can touch these areas up onsite by filling any indentations and reapplying a topcoat with a brush (so no lengthy setup or messy cleanup required!).

Certified Applicators of Intumescent Coating Systems

The most important factor in ensuring an intumescent coating system is well maintained is ensuring the initial application is to the manufacturer’s specifications. This includes the steel being properly prepared for the coating. The best way to achieve this is to work with certified applicators of intumescent systems who can complete the project from start to finish and provide a warranty on the complete system. ProFinish Coatings are an endorsed applicator of market-leading suppliers of intumescent coatings, ensuring that when you work with our team, we can choose the best products for your projects. Our sandblasting facilities ensure the steel can be prepared and stored in a controlled environment.

The expert team at Pro Finish Coatings have an intimate knowledge of passive fire protection products and can assist you with any queries you have. The team can provide you with competitive quotes, helpful information and back it all up with exceptional service.

Get in touch by phone (03) 5274 1226, email or via our contact form.

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