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Protecting Exposed Steel In Your Extension From Fire

Extensions are extremely useful, on residential and commercial properties alike. They can be used to create space for storage, offices, workrooms, playrooms and much more. If your extension has exposed steelwork, you will need to protect it from potential fire damage. Exposed steelwork can either be practical or make an interesting design feature. Although steel is a sturdy material, you do need to implement fire safety measures.

Protecting a steel exposed extension at home

Priming Steelwork

In order to achieve the best results for any paints, coatings or decorative finishes, it’s a good idea to prime the surface. With fire retardant systems it will more often than not be an essential step in the process. Steel can rust over time, so by using an anti-corrosion primer it’s possible to protect the steel or even rejuvenate rusted steelwork. Even if the exposed steelwork in your extension is on the inside, it’s still open to potential damage. Remember; you may need a specific primer tested and/or recommended by the manufacturer of the fire retardant system you choose to protect and decorate the steelwork in your extension.

Protecting Steelwork

Fire resistance steel paint coverage times

When it comes to fire protection, an intumescent paint can provide a range of different levels of protection from 30 minutes right up to 2 hours. This protection time gives firefighters time to access and put out a fire and people time to escape the building. It’s possible to use paints that take the hard work out of calculating how much you need to achieve the fire protection you require, making it easier for you to make updates to your extension. Additionally, using a fire protective coating will help to contain the spread of fire. In your extension, think about both the internal and external exposed steel while it’s easily accessible to paint and consult your authority as early as possible in the project. Seeking advice will ensure you protect the right steels to the correct level. Make sure you use a paint that is up to fire standards and meets any building regulations that may apply to your extension.

Finishing Steelwork

To decorate and protect your steelwork, it’s important (like the primer) to use a paint which is approved by the manufacturer of the intumescent paint you have chosen. The requirement for a protective topcoat differs from intumescent to intumescent but as a general rule of thumb, any external steel will always require a topcoat and any internal steel that is remaining visible at the end of the project will require a topcoat. Each product in the fire protection system plays its own part – the primer protects against corrosion and provides good adhesion to the steel, the intumescent protects the steel from fire for the length of time required and the topcoat allows the user to achieve the colour and finish required on the steel while protecting the intumescent paint from damage (moisture, cleaning, weather, general wear and tear, etc.).

Combine these three steps to effectively protect the exposed steel in your extension. If you have any questions about making sure your building is protected from hazards such as fire, contact the team at Rawlins Paints to find out how you can make your property safer.

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  1. A fantastic guide to protecting your extension.

  2. Hi i am currently converting a stone barn My client has expressed a wish to leave the internal steel structure visible. I have already installed the timber joists and the first floor caber flooring . Is it possible to paint the steel to comply with building regs / fire regs.If so do you have a product that io can use to acheive this.Many thanks Ahearne Builders

  3. Hi We have a steel H beam above our flat roof kitchen 4 metres long and 25 cm x 25 cm
    I simply need to protect it with paint and I’m getting a run around. What do you suggest
    Thank you

    • Hi Keith,

      Thank you very much for your question, to answer this fully please could you forward on some more information as per the below:

      – Level of fire protection required (i.e. 30, 60, 90min, etc.)
      – Each steel section dimension (i.e. 254 x 146 x 37 UB)
      – Quantity and length of each section (or overall meterage for each section)
      – Orientation (horizontal or vertical)
      – Number of sides to be painted (all sides, 3 sides, 1 flange, etc.)
      – Environment (internal, external, chemical exposure, etc.)
      – Application on site or in shop

      Alternatively you can just forward us drawings, fabrication/cutting lists and we’ll extract the information from them but in that instance we’d need some guidance as to what to allow for i.e. all steels on first floor, etc.

      You are very welcome to get back to us with this information via email if you would prefer at [email protected] – our Technical Team will be very happy to assist.

      Thank you again for your question, and please feel free to get in touch if you need any further information.

      Many thanks

  4. Hi. Our steels are already installed. We want to leave them exposed. Two are horizontal and 3 sides are exposed, the other is flush with a wooden beam. One is vertical against a brick wall. So we don’t have access to paint all sides. Is this a big problem?

    • Hi Dee,

      Thank you very much for taking the time to read our blog and for your question. Our Technical Team will be happy to assist with your query, so we have all of the information we will need to provide a specification please could you fill in the Thermoguard Steel Enquiry Form and return it to [email protected]. You can also call the Technical Team on 0113 2455450 (option 2) if you need any further information.

      I hope this helps and we hope to hear from you soon.

      Many thanks

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