CAVITY TRAYS LTD

ADMINISTRATION CENTRE
BOUNDARY AVE
LUFTON TRADING ESTATE
YEOVIL
SOMERSET BA22 8HU

Tel: 01935 474769
Fax:

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Suppliers of: Cavity tray, Cavity tray unleaded, Cavity tray with lead, Cavity tray horizontal, Cavity tray refurbishment, Cavity tray gable abutment, Cavity tray conservatory, Cavity tray building regulations, Cavity tray NHBC, Cavity tray non combustible

Cavity Trays Ltd -Manufacturers of Cavity trays, DPCs, Radon Protection, Roof ventilation products &  Cavity closers.

The only cavity tray manufacturer awarded European Technical Approval (ETA).

 

Useful Resources:

Main Product Ranges:

Damp Proofing Products:

A wide selection of Cavity Trays, profiled DPCs and ancilliary products for all construction methods. Cavity trays can be supplied in all sizes and shapes from load bearing lintels to masonry support systems. Damp proofing Courses (DPCs) are available in preformed & profiled systems to provide excellent Damp Proofing Solutions. Other products include weep vents, flashings, remedial products and arresting barriers for all damp proofing problems.

Radon Products:

Cavity trays can also supply an extensive range of Membranes for all applications. These include: * Contaminated Land Gas Reception Sump * Gas and Water Outlets and Service Entry Points * Methane Barriers * Radon (Cavity) Barriers * Service Pipe Entry Seals (top hats) * Type N Sitesealer Membrane

Ventilation Products:

Cavity Trays supply a wide range of products to solve ventilation problems on all contruction projects. Products include: Air bricks, sleeves, Ventilators, Roof vents, roofline Ventilation for Soffits, eaves and Fascias.

Associated Products:

Cavity Trays offer a wide range of associated products to include: Masonry Attachment Profiles, Loft access doors & hatches, Eaves Protection, Bonding strips and valley gutters.

Cavity Closer Ranges:

Cavity Trays supply a wide range of Cavity Closers for all construction & refurbishment methods. Products include: Bespoke Traditional Cavity Closers, Fire integrity stops & barriers, Acoustic barriers, waterproof barriers, insulated cavity closers & barriers.

Main Product categories:

Cavity tray, Cavity tray unleaded, Cavity tray with lead, Cavity tray horizontal, Cavity tray refurbishment, Cavity tray gable abutment, Cavity tray conservatory, Cavity tray building regulations, Cavity tray NHBC, Cavity tray non combustible, Cavity tray NBS, Cavity tray flat roof, Cavity tray pitched roof, Cavity tray roof abutment, Cavity tray retrofit, Cavity tray rendered wall, Cavity tray roof, Weep, Weep rendered wall, Weep adjustable

ACCESS DOORS Ceilings
ACCESS DOORS Walls Loft Eaves Access
ACCESS HATCHES See Also ACCESS COVERS: See Also ROOF ACCESS HATCHES:/LOFT ACCESS DOORS:
ACCESS PANELS Ceiling
AIR BRICK Adaptors
AIR BRICK Ducting Connectors
AIR BRICK Sleeves
AIR BRICK Ventilators Telescopic Adjustable
AIR BRICKS .
AIR BRICKS Ducted Cavity Liner
AIR BRICKS Ground Gas Venting
AIR BRICKS Polypropylene
AIR BRICKS Ventilation
CABLE CONDUITS Floor Ducting
CABLE CONDUITS Floor Ducting In-Screed Trays
CABLE CONDUITS Floor Ducting Screeded Floor
CAVITY BARRIERS Acoustic
CAVITY BARRIERS Acoustic Fire Rated 120 Minutes
CAVITY BARRIERS Acoustic Fire Rated 240 Minutes
CAVITY BARRIERS Acoustic Fire Rated 60 Minutes
CAVITY BARRIERS Fire Resistant Acoustic Building Regs Part E
CAVITY BARRIERS Fire Resistant BS 476:1987 Parts 20/22 60 Minutes
CAVITY BARRIERS For Cladding Systems
CAVITY BARRIERS For Rainscreen Systems
CAVITY BARRIERS Methane Gas Resistant
CAVITY BARRIERS Party Walls BS 476 150 Minutes
CAVITY BARRIERS Party Walls DPC Combined
CAVITY BARRIERS Radon Gas Barriers
CAVITY BARRIERS Robust Details Requirements
CAVITY BARRIERS Timber Frame Applications
CAVITY BARRIERS Ventilated Cavities Fire Seals
CAVITY BARRIERS Ventilated Cavities Fire Seals BS 476 Part 20
CAVITY BARRIERS Ventilated Cavities Fire Seals Cladding Systems
CAVITY BARRIERS Ventilated Cavities Fire Seals Rainscreen Systems
CAVITY BARRIERS Ventilated Cavities Fire Seals Timber Frame Constructions
CAVITY CLOAKS .
CAVITY CLOSERS Acoustic
CAVITY CLOSERS Acoustic Fire Resistant
CAVITY CLOSERS AGREMENT CERTIFICATE HOLDERS
CAVITY CLOSERS Ground Bearing Floor Insulating Perimeter Systems
CAVITY CLOSERS Ground Bearing Party Wall Insulating Systems
CAVITY CLOSERS Insulated
CAVITY CLOSERS Insulated AGREMENT CERTIFICATE HOLDERS
CAVITY CLOSERS Insulated Cavity Fire Barrier Combined
CAVITY CLOSERS Insulated Custom Sizes
CAVITY CLOSERS Insulated DPC Combined
CAVITY CLOSERS Insulated DPC Combined Refurbishment
CAVITY CLOSERS Insulated DPC Combined Sash Frame
CAVITY CLOSERS Insulated DPC Support
CAVITY CLOSERS Insulated Fire Resistant BS 476 Part 20: 30 Minutes
CAVITY CLOSERS Insulated Fire Resistant BS 476 Part 20: 60 Minutes
CAVITY CLOSERS Insulated Fire Resistant BS 476 Part 20:120 Minutes
CAVITY CLOSERS Insulated Fire Resistant BS 476 Part 20: 90 Minutes
CAVITY CLOSERS Insulated Fire Resistant BS 476 Part 20:240 Minutes
CAVITY CLOSERS Insulated Sound Reducing
CAVITY CLOSERS NHBC/Zurich/Premier Requirements
CAVITY CLOSERS Purpose Made
CAVITY CLOSERS Reveal Closers
CAVITY CLOSERS Robust Details Requirements
CAVITY CLOSERS Wide Cavity
CAVITY CLOSING DPCs Preformed
CAVITY CLOSING DPCs Purpose Made
CAVITY DRAINAGE Membranes
CAVITY DRAINAGE Waterproofing Membranes
CAVITY FIRESTOPS Cavity Wall Insulation
CAVITY FIRESTOPS Sloping Barriers
CAVITY STOPS DPC Combined
CAVITY TRAYS Abutment Gable Abutments
CAVITY TRAYS Acoustic
CAVITY TRAYS AGREMENT CERTIFICATE HOLDERS
CAVITY TRAYS Arch Window
CAVITY TRAYS Balcony Openings
CAVITY TRAYS Blockwork
CAVITY TRAYS BS 5628:Part 3
CAVITY TRAYS BS 8215
CAVITY TRAYS Building Extension
CAVITY TRAYS Building Regs.
CAVITY TRAYS Bullseye Window
CAVITY TRAYS Circular Window
CAVITY TRAYS Conservatory Attachment
CAVITY TRAYS Curved
CAVITY TRAYS Door Openings
CAVITY TRAYS ETA European Technical Approval
CAVITY TRAYS Gas Barrier
CAVITY TRAYS Horizontal
CAVITY TRAYS Insulating
CAVITY TRAYS Integral Flashing
CAVITY TRAYS Lead Substitute
CAVITY TRAYS Leaded
CAVITY TRAYS Lintel
CAVITY TRAYS Masonry Support
CAVITY TRAYS Meter Boxes
CAVITY TRAYS NHBC Standards
CAVITY TRAYS Non-Combustible BS EN 13501-1:2007 Euroclass A1
CAVITY TRAYS Non-Combustible BS EN 13501-1:2007 Euroclass A2
CAVITY TRAYS Parapet
CAVITY TRAYS Party Walls
CAVITY TRAYS Pitched Roof
CAVITY TRAYS Polypropylene
CAVITY TRAYS Preformed Horizontal
CAVITY TRAYS Purpose Made
CAVITY TRAYS Refurbishment
CAVITY TRAYS Remedial
CAVITY TRAYS Renewal
CAVITY TRAYS Ridge
CAVITY TRAYS Sill Forming
CAVITY TRAYS Stepped
CAVITY TRAYS Stone Mullion
CAVITY TRAYS Threshold
CAVITY TRAYS Threshold Level Thresholds
CAVITY TRAYS Timber Frame Constructions
CAVITY TRAYS Undersill
CAVITY TRAYS Vertical
CAVITY TRAYS Wall Weeps Beak Pyramid Masony Bleed Straw
CAVITY TRAYS Wall Weeps Non-Combustible BS EN 13501-1:2007 Euroclass A1
CAVITY TRAYS Wall Weeps Telescopic Adjustable
CAVITY TRAYS Weep Combined
CAVITY TRAYS Window Openings
CAVITY TRAYS Window Sill
CAVITY WALL Links
CAVITY WALL Sleeves Fire Protection
CAVITY WALL Ventilators
CAVITY WALL Ventilators Methane Gas Discharge
CAVITY WALL Ventilators Passive Radon Gas Evacuation
CAVITY WALL Ventilators Weep Combined
CAVITY WALL Weeps:
CAVITY WALL Weeps: Non-Combustible BS EN 13501-1 2007 Euroclass A1
CAVITY WALL Weeps: Weep Hole Ducts
CAVITY WALL Weeps: Weep Hole Ducts Concealed
CAVITY WALL Weeps: Weep Vents
CAVITY WALL Weeps: Weep Vents Non-Combustible BS EN 13501-1:2007 Euroclass A1
CHIMNEY Flashings
DAMP PROOFING Purpose Made
DAMPCOURSE Accessories
DAMPCOURSE Fixing Strips
DAMPCOURSE Jointing Tape
DAMPCOURSES Arched
DAMPCOURSES Arched Insulating
DAMPCOURSES Arched Insulating AGREMENT CERTIFICATE HOLDERS
DAMPCOURSES Cavity Closer Combined
DAMPCOURSES Cavity Closing
DAMPCOURSES Cavity Tray
DAMPCOURSES Cavity Tray Gas Resisting
DAMPCOURSES Gas Resistant
DAMPCOURSES Gas Retardant
DAMPCOURSES Horizontal
DAMPCOURSES Insulating
DAMPCOURSES Methane Barrier
DAMPCOURSES Petheleyne
DAMPCOURSES Polyethylene BS 6515:1984
DAMPCOURSES Polypropylene
DAMPCOURSES Preformed Profile
DAMPCOURSES Preformed Profile Circular
DAMPCOURSES Preformed Profile Cloaks Combined
DAMPCOURSES Preformed Profile Curved
DAMPCOURSES Preformed Profile Party Wall System
DAMPCOURSES Preformed Profile System Building Applications
DAMPCOURSES Preformed Profile Timber Frame and SIPs Constructions
DAMPCOURSES Preformed Profile Timber Frame Constructions
DAMPCOURSES Preformed Units
DAMPCOURSES Purpose Made
DAMPCOURSES Vertical
DAMPCOURSES Vertical Insulating
DUCTING Floor In-Screed Trays
DUCTING Underfloor Screed Floor Ducting
EAVES Bird Vermin Barrier
EAVES Continuous Course
EAVES Filler Combs
EAVES Guards Gutter Drip
EAVES Protection Systems Vented Eaves Protectors
EAVES VENTS Corbel
EAVES VENTS Insect Screen Incorporated
EAVES VENTS Over Fascia
EAVES VENTS Refurbishment
EAVES VENTS Roll Form
EDGE INSULATOR DPC
FABRICATIONS Bespoke Leadwork
FASCIAS Ventilated
FIRE BARRIERS Acoustic Tray Combined
FIRE BARRIERS Cavity Tray Combined
FIRE BARRIERS Cavity Wall
FIRE BARRIERS Floor Level
FIRE PROTECTION For Rainscreen Cladding
FIRESTOPS Acoustic Tray Combined
FIRESTOPS Cavity Tray Combined
FIRESTOPS Floor Level
FIXINGS Masonry Attachment Profiles
FLASHING Anchoring Systems
FLASHINGS AGREMENT CERTIFICATE HOLDERS
FLASHINGS Colourcoated
FLASHINGS For Profiled Sheets
FLASHINGS Lead
FLASHINGS Lead Chimney Stack
FLASHINGS Lead Purpose Made
FLASHINGS Non-Lead Leadfree
FLASHINGS Synthetic AGREMENT CERTIFICATE HOLDERS
FLASHINGS Synthetic Anti-Theft
FLASHINGS Ventilating
FLAT ROOF Vents
GROUND GAS Sumps
JOIST Gloves
LEAD SHEETS .
LEAD SHEETS BS EN 12588:1999
LINTEL DPC Trays
LINTEL Stop Ends
LINTELS Cavity Tray Combined
LINTELS Steel Roller Shutter Combined
LOFT ACCESS DOORS 0.35 U Value
LOFT ACCESS DOORS BRE and NHBC
LOFT ACCESS DOORS Building Regs. Approved Document L
LOFT ACCESS DOORS Fire Rated
LOFT ACCESS DOORS Fire Rated BS 476:Part 22 .1/2 hour / 30 Minutes FR30
LOFT ACCESS DOORS Fire Rated BS 476:Part 22 1 Hour / 60 Minutes
LOFT ACCESS DOORS Fire Rated BS 476:Part 22 2 Hour / 120 Minutes
LOFT ACCESS DOORS Insulated
LOFT ACCESS DOORS Insulated PVC
LOFT ACCESS DOORS Loft Hatches
LOFT ACCESS DOORS Loft Hatches Insulated BS 476:Part 20 60 Minutes
LOFT ACCESS DOORS Loft Hatches Insulated Building Regs Document L1/L2 Compliant
LOFT ACCESS DOORS Non-Combustible
LOFT ACCESS DOORS Non-Combustible BS 476 Part 6: Class 0
LOFT ACCESS DOORS Part L 2010 Compliant
LOFT ACCESS DOORS Steel
MASONRY SUPPORT SYSTEMS Cavity Tray
MEMBRANES Carbon Dioxide Retardant CO₂ Barrier
MEMBRANES Cavity Drain / Cavity Former See Also CAVITY DRAINAGE: Membranes
MEMBRANES Contaminated Land
MEMBRANES Damp Proofing DPM
MEMBRANES Gas Barrier
MEMBRANES Gas Retardant
MEMBRANES Loose Laid Oversite
MEMBRANES Loose Laid Radon and Methane and CO₂ Resistant
MEMBRANES Loose Laid Radon and Methane Resistant
MEMBRANES Methane Gas Retardant
MEMBRANES Oversite
MEMBRANES Polythene
MEMBRANES Radon Barrier
MEMBRANES Radon Resistant
MEMBRANES Tanking .See Also MEMBRANES: Waterproofing
NOISE CONTROL Barriers .See Also ACOUSTIC BARRIERS:
PIER Cloaks
PIPE Entry Seals Top Hat
RADON Barriers
RADON Barriers Loose Laid
RADON Cavity Barriers Radon Gas Resistant
RADON Cavity Barriers Threshold Protection
RADON Gas Evacuation Passive Gas Extraction Airbricks
RADON Protection Systems
RADON Sumps
RAINSCREEN BAFFLES
RAINSCREEN SYSTEMS Cladding Fire Barriers
RENDER PROTECTION COVERS Grille Protection Covers
ROOF Space Ventilators
ROOF ACCESS HATCHES Hinged
ROOF FINISH Bonding Strips
ROOF TRIM Continuous Soaker Systems For Slate and Tile Roofs
ROOF TRIM Soaker Strips For Slate and Tile Roofs
ROOF VALLEYS Troughs Gutters
ROOF VALLEYS Troughs GRP Gutters GRP
ROOF VALLEYS Troughs GRP BS 5534
ROOF VALLEYS Troughs Simulated Lead Gutters Simulated Lead
ROOF VENTILATORS .
ROOF VENTILATORS Abutments
ROOF VENTILATORS Dry Ridge
ROOF VENTILATORS Flush Slate
ROOF VENTILATORS Hip
ROOF VENTILATORS Lead
ROOF VENTILATORS Lead BS EN 12588:1999
ROOF VENTILATORS Over Fascia
ROOF VENTILATORS Slate Extract Vents
ROOF VENTILATORS Soffit
ROOF VENTILATORS Tile Vents
ROOF WINDOW Ventilation
ROOFING Felt Support Trays
ROOFING MEMBRANES Pitched Roof Underlay Undertiling Underslating See Also ROOFING UNDERLAYS PITCHED ROOF MEMBRANES:
ROOFING SLATES Roof Weathering Slates Lead
ROOFING SLATES Vent Terminals
ROOFING UNDERLAYS PITCHED ROOF MEMBRANES Barrier Membranes
ROOFING UNDERLAYS PITCHED ROOF MEMBRANES Undertile
ROOFING UNDERLAYS PITCHED ROOF MEMBRANES Warm Roofs
ROOFLINE Eaves Vents .See Also EAVES VENTS:
SEALANTS Mastic
SEALANTS Mastic: by Special Function: Lead Flashing
SERVICE CONDUITS Ducting In-Screed
SOAKER UNITS
SOFFIT VENTILATOR STRIPS PVC-u GRP
SOFFIT VENTILATORS Circular Soffit Vents
SOFFIT VENTILATORS Continuous
SOFFIT VENTILATORS Integral Insect Screen
SOFFIT VENTILATORS Low Pitch (Below 15 degrees)
SOFFIT VENTILATORS Push In
SOFFITS Ventilated
STRUCTURAL WATERPROOFING Cavity Drainage
STRUCTURAL WATERPROOFING Drainage Systems
TRAYS Sill
VENTILATION Airbricks
VENTILATION Fascia
VENTILATION Flat Roof
VENTILATION Outlets
VENTILATION Outlets Airbrick
VENTILATION Outlets Airbrick Adaptors
VENTILATION Over Fascia
VENTILATION Roof Void
VENTILATION Soffits
VENTILATION Underfloor
VENTILATION DUCTING Wall
VENTILATION GRILLES .
VENTILATION GRILLES Insect Screen Incorporated
VENTILATION GRILLES Plastic
VENTILATION LOUVRES .
VENTILATION TERMINALS Flat Roof
VENTILATORS Gas Combustion / Gas Heat Producing Appliances
VENTILATORS Gas Combustion / Gas Heat Producing Appliances Through Wall Ventilation
VENTILATORS Through Wall Ventilation
VENTILATORS Through Wall Ventilation Anti-Draught
VENTILATORS Underfloor
VENTILATORS Underfloor Telescopic
VENTILATORS Wall
WALL VENTILATION SLEEVES
WALL VENTILATORS Cavity Wall Weep Vents
WALL VENTILATORS Natural
WALL VENTILATORS Telescopic Adjustable Sleeve
ADVANTAGE Abutment Trays
BEAK WEEP Cavity Wall Weep
CAVI 120 Cavity Closer
CAVI 120 Loft Access Doors
CAVI 150 Cavity Wall Barrier
CAVI 240 Cavity Wall Closer/DPC
CAVI 30 Cavity Wall Closer/DPC
CAVI 60 Cavity Closer
CAVI 90 Cavity Closer
CAVIBRICK Air Bricks
CAVICHECK Fire Stops
CAVICLOAK Preformed Damp Courses
CAVICLOSER Cavity Wall Closer/DPC
CAVILENGTHS Preformed Damp Courses
CAVILINK Cavity Wall Links
CAVILINTEL Lintel & Security Shutter
CAVIROLL DPC
CAVISTRAP DPC Fixing Strips
CAVITRAY Cavity Wall Trays
CAVIVENT Peep Weep Ventilator
CAVIWEEP Peep Weep Ventilator
CONESLATE Roof Weathering Slate
CONTINUITY CLOSER Cavity Wall Closer/DPC
DROPCLOAKS Preformed Damp Course
EUROWEEP Cavity Wall Weeps
HARDEDGE Roofing Felt Supports
LOFTHATCH Loft Access Door
MULTICOURSE Cavity Tray
ONE WAY Roof Underlay
PERFORM Flashings
QUICKCLOSER Cavity Wall Closer/DPC
RADON Cavity Barriers
READY DPC Preformed Damp Courses
SILICONBOND Lead Flashing Sealant
SITESEALER Oversite Radon Membranes
SITESEALER Preformed Membranes

Cavity Trays Ltd - What Is A Weep Vent?

September 2024

Cavity trays are essential components in construction, ensuring moisture control within cavity walls. One critical aspect of these trays is the weep, which facilitates drainage and ventilation. This article delves into the performance and functionality of cavity tray weep vents, with a focus on the Beak Weep manufactured by Cavity Trays Ltd. By exploring various models and their characteristics, we aim to provide a comprehensive understanding of why the Beak Weep stands out in the industry.
What are Weep Vents?

Cavity tray weep vents play a pivotal role in maintaining the integrity of cavity walls. These small outlets allow water that penetrates the outer leaf of a wall to drain out, preventing moisture from reaching the inner leaf and causing damp issues. Their design and placement are crucial in ensuring effective moisture management.
Types of Weeps

Most weep vents have minimal elevation visual presence, terminating at the elevation face with either a simple hole or a hole protected with a cover or beak. Different models offer varying levels of performance based on their design and functionality.
Weep Vent Presence and Functionality

When comparing weep vents, it is important to establish whether the viewable outlet dimensions are the smallest dimensions through which water or air flow must pass. Some open-hole models may have a weep vent outlet dimension that reduces part-way along within the moulding. Such dimension variance or restriction can impact flow measurements and overall performance.
The Beak Weep

The Beak Weep, manufactured by Cavity Trays Ltd, is designed without flow-route impingements, ensuring a consistent and effective drainage and ventilation pathway. Unlike some models, the Beak Weep aperture is protected against wind-driven rains, making it highly suitable for areas that are highly exposed.

Cavity Trays Beak Weep on orange surface
Advantages of The Beak Weep

The Beak Weep addresses the major concern of water-retention, where wind pressure can prevent evacuation and cause water to be trapped, potentially overwhelming the DPC/tray system within the wall. Additionally, the drop-outlet is dimensioned with upward radiused sides, permitting washed mortar sands to spread and drop at the outlet. This design minimizes the risk of blockage and maintains optimal functionality.
Performance in Exposed Sites

One of the standout features of the Beak Weep is its suitability for highly exposed sites. The protected outlet and high weep flow dimension ensure reliable performance even under challenging weather conditions. The radiused sides further enhance its effectiveness by allowing debris to be expelled easily.
Visual and Practical Benefits

While the advantages of the Beak Weep may not be immediately apparent upon visual inspection, its design offers several practical benefits:

Protected outlet
Highest weep flow dimension
Highest vent flow dimension
Suits highly exposed sites
Radiused sides allow spread and drop of washed
mortar debris.

Contact The Experts

To learn more about Weep Vent performance and optimisation, including dimensions and installation instructions or to enquire about any of our products, get in touch with us today or call us on 01935 474769.

The Beak Weep is manufactured by Cavity Trays Ltd, the longest-established cavity tray manufacturer.

Why Fire Rated Cavity Closers Are Essential for Modern Safety and Confinement

September 2024

Fire rated cavity closers are essential for modern building safety. They play a critical role in preventing the spread of fire and smoke through cavity walls, ensuring the safety of building inhabitants. However, their effectiveness is highly dependent on correct installation and adherence to best practices. By understanding and addressing the real-world challenges of construction tolerances, builders can ensure that these critical components perform as intended, providing vital protection in the event of a fire.

Buildings should be constructed to eliminate or minimise, as much as possible, all potential fire and fire safety risks likely to arise. The building and its inhabitants should at all times be suitably protected. In theory, this should be a fairly straightforward undertaking, but in practice, the building envelope can present both designer and builder with considerations that are not always immediately obvious.
Understanding Cavity Wall Construction

Cavity wall construction relies on the external leaf (that can become saturated with rain) from not coming into contact with the inner leaf that is required to keep dry. Wall ties are shaped to structurally link the skins and prevent rain tracking across to the inner leaf. The cavity successfully separates and isolates the two. However, in the event of a fire, both air and fire can be drawn through the cavity within all the external walls of the building, fueling combustion. This raises the question of whether there is an optimum way of protecting the external envelope at one of the most frequently occurring features—where it is punctuated by window and door openings. Such openings present the designer and contractor with the usual heat-loss and damp-transference considerations, but with multi-occupancy and numerous other structure categories, there is also the additional important requirement to protect against fire and fire transference.
The Role of Fire Rated Cavity Closers

Fire-resistant cavity closers are an accepted way of addressing window and door reveals. A typical closer contains a non-combustible thermal and fire-resistant core that straddles the cavity, effectively linking both skins. Such closers provide passive fire protection. Applied to all four sides of an opening, the completed installation provides a level of fire resistance, commonly 30 or 60 minutes.
Testing and Standards for Fire Rated Cavity Closers

To establish the number of minutes, closers are subjected to testing at a fire research station. Such stations do a good job, and accordingly, best practice construction is witnessed. Products interface squarely, correctly, and consistently. However, if one looks at the actual on-site building tolerances, they are different, prompting the question of whether currently accepted site tolerances adversely affect the performance of fire-resistant cavity closers.

Are such tolerances compatible with those required with a fire-resistant closer, bearing in mind closer and masonry must interface consistently and without gaps, to perform? Construction tolerances accepted by various authoritative bodies vary, but in general buildings, the following are commonly witnessed:
Fire Rated Cavity Closer Installation

The optimum performance of any fire-rated closer is dependent on correct incorporation. Put simply, the relationship between a fire-resistant closer and masonry should match those under which the test results were achieved. Cavity wall openings constructed to the varied tolerances shown above differ from those used by testing stations and are unlikely to replicate the test results.

Testing stations qualify their test results relate only to the behaviour of the specimens of the elements of construction under particular conditions of test and do not reflect actual behaviour in fires. All openings in cavity walls should be formed squarely and uniformly, observing best practices to fulfill the objectives and requirements of Building Regulations Approved Document Part B.
Materials and Longevity

While functionality relies on continuous interfacing, core longevity can be aided with the use of stainless-steel metal ties as opposed to plastic ties securing the closer to the masonry. Metal ties that project through the closer body and continue into the actual protective core itself can extend the period the resistant core is anchored and held in position when fire is attacking with continuous interfacing and retention being the objectives. The building fabric should be constructed so that there are ‘no reasonably avoidable gaps within various elements, at the joints between elements, and at the edges of elements such as those around window and door openings,’ as stipulated within L1A 5.9.
Fire Rated Cavity Closer Considerations

Fire testing establishments and bodies such as the BBA quite understandably do not provide warranties. It is down to those constructing the building to aspire to the highest standards to get it right. While one continues to witness variable masonry tolerances, one questions whether building envelope fire resistance will actually provide the intended level of protection in the event of a serious fire. Compliant construction should leave nothing to chance.

A site agent of many years standing poignantly summed up the situation: ‘When you buy a new car, the manufacturers often claim it can travel an impressive number of miles per litre, and I do not doubt such a figure is honestly produced, albeit dependent on a featherlight foot on the accelerator, well-inflated tires, etc. Real everyday driving is different, and thus the resultant performance/fuel consumption will be different.
Learn More

Cavity Trays is an industry leader in the design, manufacture and supply of damp-proofing, cavity closers, ventilation, and other specialist products in the construction sector.

We have decades of experience helping businesses comply with all relevant building regulations. To learn more about our Cavity Closers, including dimensions and installation instructions or to enquire about any of our products, get in touch with us today or call us on 01935 474769.

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