B-Board: The ideal lightweight fire resistant core material for timber and metal firedoors


B-Board fire protection products are often integrated as fire resistant core boards in

OEM applications such as doors, fire dampers, partition walls, thermal breakers, etc. B-Board has proven to be a succesful  fire resistant material for applications that must comply with fire classification “E” (Integrity) or “EI” (Integrity + insulation) from 60 min to 120 mins – or even more, if desired.


The B-Board range consists of 6 grades, separated into 3 families:

B-Board 150 & 160

Based on Expanded Perlite, fibers and fillers.

B-Board 260 & 270   

Based on mineral wool fibers supplemented by expanded perlite, fillers and binders.

B-Board 320 & X2 (new)

Based on High Temperature Insulating fibers (1200 °C) and other components, resulting in higher density boards for a higher temperature resistance and improved acoustic insulating properties.

These grades all share the same important characteristics such as lightness, rigidity and durability. The boards differ in fire protection behaviour. Each grade is specifically developed for achieving a particular fire classification:

B-Board 150 & 160

EI30 and EI60

B-Board 260 & 270  

EI60 and EI90

B-Board 320 & X2 (new)

EI60, EI90 and EI120

Availability and convertions
B-Board can be suplied as a monolithic, 1 layer board or multi-layered for thicker doors. Also, despite it’s stifness, B-Board is very easy to cut. B-Board can be supplied in any kind of shape. Furthermore, it is possible to add different kinds of laminates and to sand down the surfaces of the boards for minimal tolerances.

B-Board can also be a solution for improving the overall fire resistance of existing, old doors that no longer comply with the current fire safety regulations. For such applications, our intumescent fire protection paint IntuCoat can also be considered.

Guideline for fire testing

The B-Board products have been extensively tested on fire behaviour throughout the years. The data obtained from those tests allows us to make accurate estimations on the required product type and thickness for both timber and metal firedoor constructions.

The table below can be considered as a guideline for the application of B-Board as a fire, thermal and acoustic insulation core for plain timber firedoors (following EN 1634-1 / 1363-1).

Please note that this is based on average testing data for a first indicative approach. Final fire testing results depends on a number of other parameters (concept, type and positioning of intumescent joints, dimensions, choise of materials, the lock etc.)

For the joints of the firedoor, our intumescent fire sealing product IntuPaper is often used.

Contact Forfyre for a tailor made technical advise.

Time (min) B-Board 150 B-Board 160 B-Board 270  

B-Board 320


30 40 mm 30 mm
60 55 mm 45 mm 35 mm 30 mm
90 55 mm 45 mm 40 mm
120     50 mm 45 mm
180 50 mm

Integrity + Insulation

(EI1 or EI2)

30 35 mm 30 mm
60   55 mm 45 mm 40 mm
90 50 mm 45 mm
120     60 mm 55 mm

60 mm