NBS Source
I'm a manufacturer

Wetherby Modular System 3 - Brick Slip Mesh

Verified by manufacturer over a year ago

Wetherby Wall Systems Ltd | Part of ROCKWOOL Group Product certifications:
  • KIWA BDA

    KIWA BDA

    Certificate type

A framed KIWA BDA certified stone slip facade cladding system consisting of a Stone Wool insulation board, base-coated, meshed, stainless steel mesh finished off with brick slip or stone slip finish.

Jump to:
+44 (0)1942 717100 Website

Application

Suitable for use on the outside of steel or timber frame walls of new or existing domestic and non-domestic buildings, with height and boundary restrictions for some components of the system (see systems KIWA certificate for further information).

Description

A KIWA BDA certified stone slip facade cladding system consisting of either vertical timber battens or cavity spacer rails, Stone Wool insulation board, base-coated, meshed, brick slip mesh and finished off with brick slip or stone slip finish.


Features and benefits:

  • Moisture control contribute to limiting the risk of interstitial and surface condensation.
  • Will resist wind-driven rain penetration across the partially ventilated cavity to the supporting wall.
  • Designed to adequately resist impact damage and wind loads normally encountered in the UK.
  • Classified as European class A1 in accordance with BS EN 13501-1 when incorporating Wetherby Cavity Spacer Rails.
  • Classified as European class A2-s1, d0 in accordance with BS EN 13501-1 when incorporating timber battens.
  • Improves the thermal performance of external walls and can contribute to satisfying the requirements of the National Building Regulations.
  • Service life durability of the System will depend on the environment (operating conditions) in which the System will be used.


Preparation:

  • All sheathing boards must achieve minimum pull out requirements to be suitable for the system application.
  • The substrate to receive the WBS system must be completely dry and not damaged by rain/ frost to reduce the board performance in any way.
  • The board manufacturer should be consulted and pull-out tests redone before continuing if rain/ frost damage is evident.
  • The substrate shall be clean and structurally sound.
  • Sheathing boards /panel substrates should be line and level ensuring RagRails can be installed flush to the substrate.
  • Slight variances in the substrate can be overcome by using suitable packers to ensure the system is installed line and level.
  • If the walls are not line and level, the fixing lengths must be checked to ensure adequate embedment into the sheathing board /frame substrate. This will need to be confirmed on site prior to the installation of the Wetherby system.
  • Sizing of flashings, trims and beads may also require alterations.
  • Where packing out of the RagRail or Timber Batten is required, the fixing lengths may need to be increased. This will need to be confirmed on site prior to the installation of the Wetherby system.
  • All sheathing boards must be securely fixed, correctly jointed and sealed (where required) as per the board manufacturer instructions.
  • Treatment to Existing Timber/ Steel Cladding – Remove any defective areas of the existing substrate and where required make repairs ensuring the surface is ready to receive the EWI system.
  • The existing walls are to be cleaned to the satisfaction of the Contract Administrator, to remove any friable material, algae or lichen.
  • WBS Biocidal Wash can be used to treat areas of moss, algae and mould growth.

General information

Color

Grey

White

Other

Guidance for specification option:

Various colours available for Wetherby Brick Slips.

Finish

Brick

Guidance for specification option:

The System is finished with adhesive mortar, scrim cloth and brick slips bedded into brick slip adhesive mortar.

Material

Mineral wool

Guidance for specification option:

Insulation boards.

Aluminium

Guidance for specification option:

Rails.

Timber

Guidance for specification option:

Spacer support battens/ rails.

Steel

Guidance for specification option:

Galvanized steel rails.

Shape

Rectangle

Square

Length

Bespoke

Width

Bespoke

Height

Bespoke

Warranty description

Ten year

Uniclass

Ss_25_45_72_70 Rail-fixed external wall insulation systemsPrimary

CAWS

M21/20 External wall insulation systems

M21/210 Rendered external wall insulation systems

SKU Code

20-147-S-A-UK

Specification data - Rail-fixed external wall insulation systems

Classification data

System performance

Thermal Performance.

Guidance for specification option:

The systems can improve the thermal performance of external walls and can contribute to satisfying the requirements of the National Building Regulations.

Strength and Stability.

Guidance for specification option:

The systems has adequate strength and is designed to adequately resist impact damage and wind loads encountered in the UK. When the system incorporates a stone slip finish, the system can only be applied at ground and first floor level (maximum 6 m in height). 

System Tested to BS EN 13501-1.

Guidance for specification option:

Achieve a value of A1 reaction to fire classification. Metal cavity rails must be used above 18 m and Timber battens are acceptable for anything less than this.

Risk of Condensation.

Guidance for specification option:

The system can contribute to a limiting risk of interstitial and surface condensation.

Durability.

Guidance for specification option:

When installed and maintained in accordance with the Certificate holders recommendations and this Certificate, the system will remain effective for at least 30 years.

Further Information.

Guidance for specification option:

For further information on the above points visit the system KIWA BDA Certificate.

Support rails and brackets

-

Material

15mm RagRail Cavity Spacer Rails.

Guidance for specification option:

  • RagRails are to be fixed down one side of the rail and through the centre of the rail hitting the studs at 300 mm centres.
  • The above would all be subject to Job Specific Detailing, including Pull Out Tests and Wind Load Calculations.

25mm RagRail Cavity Spacer Rails.

Guidance for specification option:

  • RagRails are to be fixed down one side of the rail and through the centre of the rail hitting the studs at 300 mm centres.
  • The above would all be subject to Job Specific Detailing, including Pull Out Tests and Wind Load Calculations.

25mm Timber Battens.

Guidance for specification option:

  • Timber Battens are to be fixed at every 150 mm centres.
  • The above would all be subject to Job Specific Detailing, including Pull Out Tests and Wind Load Calculations.

Manufacturer guidance

  • The RagRails or Timber Battens help to create a drainage cavity between the Sheathed frame and External Wall Insulation. This cavity will then allow for any moisture located within these areas to track down and drain out, either from the bottom of the system or into specifically designed drainage boxes.
  • Rails or Timber Battens should be installed vertically at 600 mm centres and around windows ensuring the insulation boards are fully supported.

Bracket fixings

LS 5.5 (steel frame).
R-QCP (timber frame).

Manufacturer guidance

  • The actual fixings of the Rail/ Battens will need to appropriate for the substrate that the system will be installed over.
  • Fixings and the frequency of them will be subject to pull out tests and wind load calculations. 

Base boards

-

Material

Framed substrate sheathed using Wetherby approved sheathing board.

Guidance for specification option:

The framed substrate must be sheathed using a Wetherby approved sheathing board ensuring that they achieve minimum pull out requirements to be suitable for the systems application.

Fixings

Fix boards in accordance with site conditions and manufacturer instructions.

Insulation

-

Material

Stone Wool Insulation.

Fixings

TKR Screw Range.
R-QCP Screw Range.

Manufacturer guidance

  • The Stone Wool Insulation Board are initially fixed with WBS approved fixings, combined with a suitable washer.
  • The fixings frequency, type and length would be subject Pull-Out Tests and Wind Load Calculations. 

Fire barriers and stops

-

Material

Not required.
Tenmat Intumescent Strip.

Guidance for specification option:

  • Intumescent strips must be screw fixed in place at 250 mm maximum centres, using a non-combustible screw with a head of no more than 11.5 mm diameter.
  • They should be mechanically fixed at agreed locations to form horizontal and if specified vertical fire breaks in the cavity.

Tenmat NVFB Fire Barrier.

Guidance for specification option:

Tenmat NVFB Non-Ventilated Fire Barrier – Vertical cavity closer and cavity closer around openings (where required).

Fixings

TKE Range – Steel Frame .

Guidance for specification option:

Typically used to fix fire barrier and intumescent strips to their agreed locations (Rail/ Sheathing Board/ Steel Frame).

R-UCF Screw Range screw range.

Guidance for specification option:

Typically used to fix fire barriers to their agreed locations (Timber Batten / Sheathing Board/ Timber Frame).

JT3-FR6 Stainless Steel Screw.

Guidance for specification option:

Typically used to fix NVFB fire barriers to their agreed locations (Sheathing Board/ Framed Substrate).

Beads and trims

Not required.
Deflector beads.

Movement joints

-

Form with

WBS Stainless Steel Movement Joints.
WBS PVC Movement Joints.
WBS Stainless Steel Surface Mounted Render Stop Beads.
WBS PVC Surface Mounted Render Stop Beads.

Manufacturer guidance

  • All structural movement joints must be mirrored through the EWI System. As a minimum, a render system should incorporate the movement joints every 7–10 m vertically and at every other floor level horizontally.
  • Structural Engineers will be required to confirm how much movement will occur and where movement joints are located in the substrate and give an indication where the joints will need to be installed.
  • All movement joints and surface render beads must be fully meshed in, applying silicone sealant where necessary.

Sealant

Compriband sealing tape must be installed between the insulation boards.

Guidance for specification option:

Where required.

Render carrier or reinforcement

-

Material

WBS Alkali-resistant scrim cloth incorporated into scrim adhesive.
Stainless Steel Brick Mesh applied over scrim adhesive.

Mesh size

Alkali Resistant Mesh 50 m² (roll).
Stainless Steel Brick Mesh – 1195 x 819 mm.
Stainless Steel Stone Slip Mesh – 1195 x 819 mm.

Fixings

TKE screw range.

Guidance for specification option:

  • Combined with the relevant cap/ washer, this fixing is typically used for the main fixings installed through the brick slip mesh.
  • Normally specified when fixing into the RagRail/ Cavity Spacer Rail.

R-UCF screw range.

Guidance for specification option:

  • Combined with the relevant cap/ washer, this fixing is typically used for the main fixings installed through the brick slip mesh.
  • Only specified specify when fixing into the timber batten.

Manufacturer guidance

  • Temporarily position WBS Brick Slip Mesh over the scrim adhesive and insulation boards.
  • Align the sheets using a string line or level leaving a 5 mm gap horizontally between sheets and ensuring the correct spacing for the slips vertically.
  • Temporarily fix the sheets with WBS Firtree fixings.
  • Once the sheets are in place, mechanically fix the mesh at a rate of 12 fixings per sheet as per the Wetherby fixing pattern (please contact Wetherby regarding the fixing pattern of the brick slip mesh).
  • Ensure fixings are installed at maximum 300 mm centres at building corners and around any openings.

Render

-

Material

WBS 9-25mm Brick Slips.

Guidance for specification option:

  • Butter the back of the pistol corners with WBS Brick Slip Adhesive and apply to corners and door/ window reveals.
  • Measure the distance between corners and/ or outer edges to identify the number of bricks required per course and the subsequent width of the pointing joints.
  • Cut bricks to size using a bench saw or standard tile cutter where required.
  • Apply WBS Brick Slip Adhesive to back of Brick Slips and install at the required location leaving a consistent joint between each (approximately 10 mm).
  • Stagger slips to give the appearance of conventional brickwork or install in a stack bond pattern in accordance with the required design.
  • NB. Brick Slips are manufactured using raw natural ceramics and will inevitably vary in nature.
  • Natural variations in colour, texture and dimensions may be present. It is advisable to mix slips from at least 5 boxes to minimize grouping of colours.
  • Any product deemed faulty or out of tolerance should not be applied and should be reported to Wetherby immediately. 

WBS Pointing Mortar.

Guidance for specification option:

  • Once brick slips have set, point up with WBS Pointing Mortar using a pointing gun.
  • Shape mortar to desired joint type using a pointing trowel.
  • Care should be taken not to apply WBS Pointing Mortar onto the brick slip face or pistols as this can be very difficult to remove.
  • Once pointing mortar is dry, brush down the wall to remove all loose mortar etc.

Stone Slips.

Guidance for specification option:

Contact Wetherby Building Systems for further information regarding this system. 

Decorative finish

-

Colour

-

Manufacturer guidance

See brick slip brochure and insert requirement.

System accessories

WBS Sealing Tape: Pre-compressed, expanding waterproof sealing tape.
WBS Firtree Fixings.
WBS Jointing Pieces.
WBS End Caps.
WBS EVO-STIK Silicone Sealant.
WBS APU Bead.
Roof verge extenders.
Under and over cills.
Cill extenders.
End stop profiles.

Guidance for specification option:

Insert requirement: Available in stainless steel, PVC-U or organic polyester powder-coated galvanized steel.

Corner mesh profiles.

Guidance for specification option:

Insert requirement: Available in stainless steel, PVC-U or organic polyester powder-coated galvanized steel.

Expansion joint profiles.

Guidance for specification option:

Insert requirement: Available in stainless steel, PVC-U or organic polyester powder-coated galvanized steel.

Samples required

Approved samples required.

Guidance for specification option:

  • Submit samples of Wetherby Brick Slips for approval.
  • Keep approved samples on site for the duration of the contract for inspection and comparison purposes.  
  • The manufacturer offers a product sample service, providing a small sample of the finished build-up, colour and brick slip type before a final decision is made.
  • Contact the manufacturer for further information.

Execution

Install system as per manufacturer’s instructions.

Guidance for specification option:

  • Securely fix Wetherby BSR starter track above DPC level at base of the system.
  • Mechanically fix starter track at maximum 300 mm centres, 50 mm from each end.
  • WBS 3756 base rail connectors should be used to join the tracks.
  • Drainage holes must be drilled into the back of the starter track to allow the cavity to drain.
  • Install 11 mm holes at 150 mm centres to allow for drainage and partial ventilation.
  • Any gaps behind the basetrack allowing free air movement behind the insulation should be sealed appropriately.

System completion

Inspection, documentation, O&M manuals and data sheets.

Guidance for specification option:

  • Inspection of completed installation.
  • Documentation for insulated render systems.
  • O&M manuals and data sheets relevant to the system installed.

Third-party certification

NHBC.

Dimensions

1200 x 600 mm.

Density

Stone Wool: 160 kg/m³ (outer layer), 100 kg/m³ (inner layer).

CompressiveStrength

Stone Wool: ≥10 kPa.

Guidance for specification option:

Compressive stress at 10% deformation to BS EN 826.

ThermalConductivity

0.036 W/m·K.

Guidance for specification option:

To BS EN 12667.

Reaction to fire classification

With Timber battens: Class A2-s1, d0 to BS EN 13501-1:2002.
With Wetherby Cavity Spacer Rails: Class A1 to BS EN 13501-1:2002.

Board thickness

80 mm (minimum).

Guidance for specification option:

Insert requirement.

Sustainability data

Country of material origin

Europe

Country of product manufacture

Europe

Product certifications

KIWA BDA

KIWA BDA

Wetherby KIWA BDA Modular - BAW-20-146 (Stone Wool and Brick Slips / Stone Slips with Stainless Steel Mesh)

Similar products from Wetherby Wall Systems Ltd | Part of ROCKWOOL Group

Epsitec External Wall Insulation Systems - PS1 & PS3 - External Wall Insulation Silicone Render

Epsitec External Wall Insulation Systems - PS1 & PS3 - External Wall Insulation Silicone Render

Epsitec Stone Wool Insulation Systems - PS4 & PS5

Epsitec Stone Wool Insulation Systems - PS4 & PS5

Wetherby Epsitec EPS Dash System - EPS Insulation With Dash Finish

Wetherby Epsitec EPS Dash System - EPS Insulation With Dash Finish

Wetherby Modular System 1 - Profiled EPS And Brick Slip Finish - EPS Insulation And Brick Slip System

Wetherby Modular System 1 - Profiled EPS And Brick Slip Finish - EPS Insulation And Brick Slip System

Wetherby Modular System 2 EPS Brick Slip - Stainless Steel Brick Mesh - EWI Brick Slip System

Wetherby Modular System 2 EPS Brick Slip - Stainless Steel Brick Mesh - EWI Brick Slip System

Wetherby Modular System 3 – 9-25 mm Brick Slips

Wetherby Modular System 3 – 9-25 mm Brick Slips

© 2025 Hubexo North UK Ltd. All rights reserved.