Raised Access Floor Barrier

For voids beneath raised access floors


AIM Raised Access Floor Barrier prevents the passage of flame and smoke through the under floor cavity, for at least the period of fire rating specified. AIM Raised Access Floor Barrier is made from high density Rockwool stone wool slab, faced with Class 0 impervious foil facing on both sides. It is available cut to size or in slabs suitable for cutting on site.


Raised Access Floor Barriers are required for four applications (requirements for fire barriers):

1 - Subdivision of large uninterrupted cavities

To comply with Building Regulations - 30 minutes’ integrity plus 15 minutes insulation. The AIM Raised Access Floor Fire Barrier meets and exceeds the requirements of Approved Document Part B (in England and Wales) as well as the fire safety sections of other UK Building Regulations’.

2 - Alignment under a partition, to maintain partition rating

i) 30 minute partition - 30 minutes’ integrity plus 30 minutes’ insulation

ii) 60 minute partition - 60 minutes’ integrity plus 60 minutes’ insulation.

iii)120 minute partition - 120 minutes’ integrity plus 120 minutes’ insulation
3 - Reduce flanking transmission of sound

The AIM Raised Access Floor Barrier can be used to reduce flanking transmission of sound through the void it fills by at least 21 dB RW
4 - Plenum Applications

The AIM Raised Access Floor Barrier can also be used to help create a Plenum chamber under a raised access floor system.


  • Length: 1000mm
  • Widths: 75mm, 100mm & 125mm (depending on the fire rating required)
  • Voids: 50 - 400mm (barrier to be compressed by 5%)
  • Available cut to size and supplied with the required fixing clips
  • Available in slab form for cutting on site as required
  • Foil faced (see options)
  • Also available Polythene sleeved
  • Thermal Conductivity l = 0.036W/mK


  • High density foil faced stone wool barrier
  • Thicknesses to provide ½, 1 and 2 hour fire rating
  • For use within voids up to 400mm
  • Reduces airborne transmission of sound by a minimum of 21db Rw
  • Solutions for power & communication cables


  • Prevents the passage of fire and smoke through underfloor cavities
  • Reduces airborne sound through underfloor voids
  • The product provides up to 120 minutes Integrity & Insulation when tested to BS EN 1366-4:2006+A1:2010
  • Allows for power and communications to be run below the barrier


AIM Clip
Acrylic fire rated intumescent mastic (optional extra)
Foil tape for sealing joints (optional extra) Length - 45m Widths - 100mm, 125mm and 150mm



Tested to BS EN 1366-4:2006+A1:2010.
Achieves the Euroclass rating of A1, non combustible.
The access floor and structural slab should have a proven fire rating at least equal to that of the barrier.

Fire RatingIntegrityInsulation
fire resistance
Barrier thicknessMaximum void
1/2 hour120 minutes30 minutes75mm400mm
1 hour120 minutes60 minutes100mm400mm
2 hour120 minutes120 minutes125mm400mm


AIM Raised Access Floor Barrier provides at least 21dB Rw sound reduction. The acoustic performance of the floor system must also be considered when assessing the room-to-room sound reduction figure.

Plenum Chambers

AIM Raised Access Floor Barrier may be used to create a plenum chamber however the effectiveness of the barrier is dependent on the quality of the installation. (or similar).


AIM Raised Access Floor Barrier is supplied pre-cut in 1000mm lengths and three standard thicknesses depending on the fire rating required. The product supplied is as required to fill the void.

The pre-cut product is supplied with the required fixing clips.


The AIM Raised Access Floor Barrier is also available in slab form for cutting on site as required. When ordering in slab form the clips should be purchased separately.

The product is also available fully foil enclosed for use within plenum applications. It can also be suppled polythene sleeved.

Foil tapes of 45m length and in widths of 100, 125 and 150mm for the optional sealing of joints.


Test reports WF 432725 & WF 432729 cover the use of AIM Raised Access Floor Fire Barrier in cavities up to 400mm.

Tests are conducted to BS EN 1366-4:2006+A1:2010 and the principles of TR31.


AIM Raised Access Floor Barrier is friction fitted into place in conjunction with fixing clips; it must fit tightly and completely fill the void with 5% compression.

AIM Raised Access Floor Barrier is friction fitted into place in conjunction with fixing clips; it must fit tightly and completely fill the void with 5% compression.


  • PPE abrasion resistant gloves
  • Drill
  • PPE impact resistant goggles
  • Screwdriver
  • RPE dust mask
  • Tape measure
  • Insulation saw


Products are supplied on wooden pallets with edge protection and a shower proof hood.

Products should be stored away from the elements until ready for installation.


This product does not contain moving parts and, if undisturbed in the underfloor cavity, requires no routine inspections or maintenance. It is recommended that the integrity of the barrier is rechecked if further works are carried out that may have involve disturbing the product e.g. installing new cables.


Insulation products supplied by AIM are considered to be inert articles and as such are exempt from requirements to provide a Safety Data Sheet.

A Product Safety and Handling Information Sheet is available upon request.


Global warming potential = zero

AIM fire barrier products are manufactured from stone wool insulation which is universally recognised as being a sustainable and environmentally friendly material.

Rockwool Stone Wool products may be recycled at the end of their life by Rockwool Ltd. Call 01656 868400 or email [email protected] for further details.


To order this product the following information will be required:

  • Underfloor void Height
  • Fire Performance Required
  • Approximate Quantity

Products are typically supplied in four to five working days but lead times may vary depending on existing factory commitments.

There is no minimum order quantity or value although small orders may attract transport surcharges.


Technical Support is available from our experienced sales team on 01293 582 400 or [email protected]

Our Partners & Affiliates

AIM are partners with NBS. Our products can be found on NBS Source and have been authored to NBS specification standards and have both CAWS and Uniclass 2015 classifications.

AIM are members of ASFP.

AIM are working in partership with Rockwool.

AIM are members of SRL.