Open State Cavity Barrier
An open state cavity barrier for ventilated façade systems and timber frame construction.
PRODUCT
AIM Open State Cavity Barriers (OSCB's) are
manufactured from high density Rockwool stone wool
and faced with an intumescent strip and colour coded
for ease of identification.
Open state cavity barriers allow the ventilation
necessary within the wall construction. In the event
of a fire, heat activates the intumescent strip which
expands quickly to fully close the cavity.
AIM OSCB’s have been designed and tested for use
within ventilated rainscreen façades and timber frame
construction, allowing free airflow and drainage.
Open State Cavity Barriers offer an effective fire barrier
for ventilated voids up to 425mm in width. Having
been tested to TGD 19 & the general principles of BS
EN 1363-1, they offer a superior fire rating of up to
120 minutes insulation & integrity with ventilated air
spaces within the cavity.
The AIM OSCB range is available to provide either
a 25 or 44mm air gap. For simplicity the range
also offers either a 60 or 120 minute rating for both
Integrity and Insulation.
APPLICATIONS
OSCB’s are a polythene sleeved ROCKWOOL® stone
wool and intumescent material designed for use within
open state cavities (e.g. Rainscreen systems), allowing
ventilation and drainage of the cavity under normal
conditions while providing up to 120 minutes insulation
and integrity performance in the event of a fire.
The AIM OSCB range has been successfully tested
to TGD 19 & the general principles of BS EN 1363-1
with a variety of substrates so that they can be used
in a multitude of cavity wall constructions.
The OSCB 60/25 has also been tested for use
vertically in a masonry cavity up to 425mm.
The AIM OSCB range has been tested to provide
solutions that accommodate cladding rails interrupting
the line of the barrier.
FEATURES
- Provides a 25mm or 44mm airspace
- Fire rated solutions for cavity voids up to 425*mm
- Heat activates the intumescent strip which expands quickly to fully close the cavity
- Tested in accordance with ASFP Technical Guidance Document 19 (TGD 19) & to the general principles of BS EN 1363-1
- Provides up to 120 minutes integrity and insulation performance
- Galvanised steel fixing bracket supplied as standard
- Stainless steel metal brackets available as a tested option
* The OSCB25 range can be used in cavities up to 600mm where the barrier is supported by Rockwool Duoslab insulation or equivalent
BENEFITS
- In the event of a fire, provides an effective barrier to the passage of hot smoke and fire behind the cladding system.
- Designed to enable a continuous airflow behind a rainscreen and timber frame cladding system thus helping to prevent problems of condensation.
- Flexible specification: Choice of four OSCBs deliver insulation and integrity performance up to 120 minutes.
- Quick and cost effective installation.
- Easy to install: Simple fixing procedure; OSCB25 range incorporates spring steel screws and steel hanging brackets. No specialist tools required.
- Colour coded for ease of identification
COMPONENTS AVAILABLE FROM AIM
OSCB Rainscreen
OSCB Fixing Brackets
AIM Intumescent Mastic
Coarse wound (Pigtail) Screws
Galvanised steel fixing brackets are supplied at a rate
of two per metre length. Brackets are packaged in a
separate cardboard box located at the bottom of a
pallet - the location will be marked with a label.
Fixing Brackets are designed to be easily re-profiled
by hand on site, and should be cut as necessary to
ensure they penetrate the barrier by at least 50% of its
width.
Stainless steel brackets are available as an option.
Coarse wound (Pigtail) Screws are required for AIM
OSCB 60/25 and OSCB 120/25, and are used to
secure the front-facing intumescent strip. They are
supplied at a rate of 3 per metre length and will be
packaged with the fixing brackets.
Care should be taken to ensure that the Coarse
Wound Screws protrude from the front face of the
firestop by a maximum of 25mm.
PHYSICAL INFORMATION
• Thickness - 90mm
• Width - Total cavity size (up to 425*mm) less 25 or
44mm according to the barrier required.
• Length - 1000mm
• Max Air Gap – 25 or 44mm
* The OSCB 25 range can be used in cavities up to
600mm where the barrier is supported by Rockwool
Duoslab insulation or equivalent.
PACKAGING
AIM OSCB's are generally packed into cartons and stretch wrapped onto wooden pallets with a showerproof polythene pallet cover and high quality edge protectors.
AS STANDARD
AIM OSCB’s are supplied pre-cut in 1000mm lengths,
90mm thick with widths varying according to the void
size.
The product is supplied pre-cut product complete
with the required fixing clips.
OPTION
In some instances it may be necessary to install a
cassette insert to provide a flat service for the OSCB
to close against, eg where cassette panels are being
used. Please contact AIM our experienced sales team
on 01293 582 400 or [email protected]
Stainless steel fixing clips are available on request.
TECHNICAL INFORMATION
| 60/25 | 60/44 | 120/25 | 120/44 | |
| Vertical use | Yes | No | No | No |
| Horizontal use | Yes | Yes | Yes | Yes |
| Cladding rails | Provide 60+ minutes integrity | Provide 60+ minutes integrity | Provide 60+ minutes integrity | Provide 60+ minutes integrity |
| Cavity sizes | 50mm to 425mm* | 50mm to 425mm | 50mm to 425mm* | 50mm to 425mm |
| Polythene sleeved | White colour coded | Blue colour coded | Red colour coded | Black colour coded |
| Fire rating (integrity / insulation) | ||||
|---|---|---|---|---|
| Masonry to masonry | 60/60 | 60/60 | 120/120 | 120/120 |
| Sheeting board to masonry | 60/60 | 60/60 | 120/120 | 120/120 |
Test run with combustible PIR, Rockpanel Façade, Extended Airspaces (30mm & 50mm - one hour only).
* The OSCB 25 range can be used in cavities up to 600mm where the barrier is supported by Rockwool Duoslab insulation or equivalent.
NOTE: Increased airspace reduces performance to 60 minutes.
Option for the OSCB 25 range without Coarse Wound Screws is available.
Option for the OSCB 25 range with a 'Through Fixing Clip' is avallable.
OSCB 60/25 has been tested vertically in a 425mm wide cavity, Stainless Steel Screws / Coarse Wound Screws as standard. Stainless Steel Clips available.
We hold R&D test data for Cassette Inserts & for FF102/50 to be screwed to vertical rails.
We hold test evidence showing the performance of AIM OSCB’s where the exterior cladding is a Rockpanel construction. Please contact our technical department for further details.
Test standards employed: BS EN 1363-1 & TGD19.
The OSCB range has been exposed to BS 8414 Fire performance of external cladding systems fire tests and assessed to BR135 to achieve pass results with a variety of third party cladding systems.
The AIM OSCB Range has been tested with masonry façades to establish the performance of the product itself without being influenced by the supporting structure. It may be used with a variety of façade types however this should involve the consideration and approval of a competent person.
TEST REPORT
| Assessment Report | Basic Details of Test |
|---|---|
| A variety of test reports are available but the suitability of the OSCB range is encapsulated within these assessments |
|
| WF417032A | ASSESSMENT COVERING OSCB 60/25 |
| WF417032B | ASSESSMENT COVERING OSCB 120/25 |
| WF417032C | ASSESSMENT COVERING OSCB 60/44 |
| WF417032D | ASSESSMENT COVERING OSCB 120/44 |
APPLICATION DETAILS
More drawings available in the Technical Guide which can be downloaded above.
INSTALLATION GUIDELINES
AIM Open State Cavity Barriers should be installed in accordance with the Fixing Instructions supplied with every order.
The installation sequence is outlined within our Technical Guide available to download here.
ITEMS REQUIRED FOR INSTALLATION
- PPE abrasion resistant gloves
- PPE impact resistant goggles
- RPE dust mask - FFP3
- Sharp knife
- Tape measure
- Insulation saw
- Acrylic fire rated intumescent mastic (optional extra)
STORAGE
Products are typically supplied in cartons on wooden pallets with edge protection and a shower proof hood. Products should be stored away from the elements until ready for installation
MAINTENANCE
This product does not contain moving parts and,
if undisturbed in the cavity, requires no routine
inspections or maintenance.
It is recommended that the integrity of the barrier is
rechecked if further works are carried out, which may
involve disturbing the product.
DURABILITY
AIM fire barriers are chemically inert, will not sustain vermin and do not encourage the growth of rot, fungi, moulds or bacteria. They are compatible with all normal building materials. They do not degrade under the usual conditions found in buildings and will perform effectively for the life of the building.
HEALTH & SAFETY
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.
ENVIRONMENT
Global warming potential = zero
For product recycling please contact: Rockwool
T: 01656 868400 E: [email protected]
ORDERING
To order this product the following information will be
required:
• Cavity depth in mm
• Fire Performance required
• Approximate quantity
• Delivery location
All AIM fire barriers are made to order. Products are
typically supplied in seven to ten 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
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 Centre for Window and Cladding Technology & ASFP.
AIM working in partnership with Rockwool.