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  • Writer's pictureAdam Sawyer

BS EN 13501-1 Class B for Wood

Updated: Dec 17, 2023


The BS EN 13501-1 classification system is used to assess the fire safety of various materials. This system determines how quickly a material will ignite and emit heat and how quickly it will burn and emit smoke.

Wood can be classified from B to F by analysing test data. To achieve a Euroclass B standard, fire retardant products can be applied to wood that is normally classified as D to F.

How to treat raw wood with intumescent fire retardant to achieve Euroclass B

Step 1: Choose the right intumescent fire retardant for the type of wood you are treating.

Step 2: Measure the wood and determine the amount of intumescent fire retardant needed.

Step 3: Apply the intumescent fire retardant on the wood surface according to the manufacturer's instructions.

Step 4: Allow for the intumescent fire retardant to thoroughly dry according to manufacturer instructions.

Step 5: Use a top coat to protect the intumescent fire retardant. One or two coats should be enough depending on where the wood will be used.

Step 6: Monitor the wood periodically for any signs of wear or damage.

Painted or varnished wood treatment to achieve Euroclass B

To properly treat painted or varnished wood, apply an adhesion primer before following the same steps as if you were treating raw wood.

Case Study Worth School Euroclass B

Contractors renovating part of the school got in touch with us to treat larch plywood to Class B standards. They told us the dimensions of the wood panels, and we figured out the total square metres of wood.

We calculated the quantities of intumescent fire retardant and top coat needed by analysing the data. By doing this, we were able to calculate an estimate for the materials and labour expenses.

After the quote was accepted, a date was set to apply the fire retardant. It is important to consider that the humidity and temperature must be at optimum levels for intumescent coatings to be applied, limiting the months when they can be used.

After the fire retardant and top coats were applied, a BS EN 13501-1 Class B certificate was issued.

How to get your wood treated to Euroclass B

If you require Euroclass B treatment for your wood, we are here to help. To start the process and receive a personalized quote, simply follow these steps:

  1. Visit our dedicated Fireproofing Wood webpage:

  2. Complete the "Get Your Quote" form with the necessary details about your project, such as the type of wood, dimensions, and desired treatment.

  3. Alternatively, you can give us a call at 07970 522475, and our experts will gladly assist you in determining the best solution for your needs.

For more information about our fireproofing services, visit our website at

Our team is committed to providing you with the highest level of customer service and ensuring your wood meets Euroclass B standards.


About the Author: Adam Sawyer

Adam is an industry expert with over 35 years of experience in textile care and fire retardant treatments. He is the founder of Fireproofing, a company specializing in fire retardant spraying and application services for curtains, fabrics, upholstery, wood, and more. With a strong commitment to customer satisfaction and safety, Adam has built lasting relationships with clients and established a reputation for excellence in the field. To learn more about Adam and Fireproofing, visit About Us & Our Expert.



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