Intermediate Project dependent

Woodland Timber Cladding Installation

Install Woodland Timber 333mm exterior PVC-U boards on vertical treated battens with concealed stainless-steel fixings, continuous ventilation and aluminium finishing trims.

Before You Start

These instructions apply only to DuraKlad Woodland Timber 333 × 7mm exterior boards installed horizontally. Store packaged boards flat, dry and away from direct sunlight. Check the labels, colour, grain direction and condition before cutting. Do not install below 5°C or above 25°C.

Project Design

Woodland Timber is a non-structural exterior rainscreen. A competent designer must confirm the substrate, batten and wall fixings, membrane, insulation, cavity barriers, flashings, wind-load spacing and fire suitability for the building. Obtain the current Woodland aluminium-trim fixing detail from Kalsi Technical before starting.

What You'll Need

Tools

  • Tape measure and pencil
  • Spirit level or laser level
  • Fine-tooth saw or suitable circular saw blade
  • Mitre saw or mitre box for trim cuts
  • Drill/driver
  • Sealant gun and clean cloths
  • PPE: eye protection, gloves and dust mask when cutting

Materials

  • Woodland Timber 333mm x 7mm x 5000mm boards
  • Starter trim and ventilation profile
  • Powder-coated aluminium edge trims
  • Internal and external corner trims
  • Division or H trims for joints where required
  • Treated timber battens, minimum 22 × 30mm
  • 70mm-wide treated battens at corner details
  • 30mm stainless-steel screws or cladding nails
  • Breathable membrane and insulation where the wall design specifies them

Technical Specifications

Board Size: 333mm x 7mm x 5000mm
Coverage: 1.665m² per 5m board
Material: PVC-U
Finish: Embossed timber effect
Orientation: Horizontal
Batten Centres: 300mm maximum, fixed vertically
Fixings: 30mm stainless-steel screws or cladding nails
Expansion: 8mm at each board end
Clear Cavity: 22mm minimum; 30mm in front of insulation
Installation Temperature: 5°C to 25°C
Trim System: Woodland powder-coated aluminium trims

Technical basis: Kalsi's published Woodland product dimensions and trim range, with the board-framework, cavity, concealed-fixing and movement values taken from the manufacturer installation method for the matching 333 × 7mm Double Embossed board format. Obtain the current Kalsi-controlled Woodland fixing, aluminium-trim, opening and fire-performance schedule for the project before installation.

Fixing Method

Ventilated Batten Framework

Fix Woodland only to a straight, vertical treated-timber batten framework that provides continuous drainage and ventilation.

  • Minimum 22 × 30mm battens at no more than 300mm centres
  • Minimum 70mm-wide battens at internal and external corners
  • 22mm clear cavity, or 30mm clear in front of insulation

Woodland-specific Details

The board framework and concealed fixing values follow the matching 333mm Double Embossed system. Use the current Woodland instruction for its aluminium trims.

  • Confirm trim fasteners and fixing centres with Kalsi Technical
  • Use matching Woodland joint, edge and corner components
  • Do not adhesive-fix boards directly to a wall or sheet substrate

Step 1: Surface Preparation

1a

Assess the wall

Confirm the wall is stable and resolve cracks, leaks or damp. Install the specified vapour-open membrane and flashings before battens where the wall design requires them. Do not use the cladding to brace the wall.

1b

Set out the batten line

Fix minimum 22 × 30mm treated battens vertically at no more than 300mm centres, using wall fixings selected for the substrate and project loads. Keep them straight and in one flat plane. Use battens at least 70mm wide at corners and support every board end, trim and opening.

1c

Plan ventilation and movement

Maintain an uninterrupted 22mm clear cavity without insulation, or at least 30mm clear between insulation and the board backs. Keep insulation behind the battens. Leave 22mm clear beneath the lowest board and above the highest board, protected against insects without blocking airflow.

Step 2: Install Starter and Trims

2a

Fit the starter trim

Set the bottom batten line 55mm above finished ground and fix the ventilation profile with the starter trim against the batten faces. Keep 22mm clear below the first board and check the starter is level.

2b

Install corner and edge trims

Fit the base sections of the matching Woodland aluminium edge, internal-corner, external-corner and joint trims before the boards. Use the fastener type and centres stated in the current Woodland trim instruction; do not copy a PVC trim fixing schedule onto aluminium components.

2c

Dry-fit first

Dry-fit trims and lay out boards from several packs before fixing. Confirm the intended tonal mix and keep the timber grain running in a consistent direction. Leave 8mm movement allowance at both ends of every board.

Step 3: Cut and Fit Boards

3a

Measure and cut

Measure each board position individually. Cut with a fine-tooth blade, support the board while cutting and avoid chipping the printed timber-effect face.

3b

Fit the first board

Locate the first board in the starter trim, check it is fully seated and level, then fix through the concealed fixing edge into every batten using 30mm stainless-steel screws where possible, or 30mm stainless-steel cladding nails.

3c

Continue across the wall

Engage each tongue-and-groove joint fully, using a nylon hammer carefully where required, then fix the concealed edge at every batten. Maintain 8mm at each board end and check level regularly.

3d

Use division trims where required

Use the matching Woodland H or division trim at board joints and support it on the batten framework. Keep 8mm movement allowance on each side of the joint and fit the aluminium trim cover in accordance with the current Woodland detail.

Step 4: Openings and Obstructions

Windows and Doors

Support every board end and trim base. Use the current Kalsi Woodland head, sill and reveal detail so flashings drain outwards, the cavity remains ventilated and 8mm board-end movement is retained inside trims.

Pipes and Services

Avoid penetrations where possible. Where required, support the opening, allow for board movement and use a compatible sleeve, collar or flashing that directs water outwards. Do not rely on sealant alone.

Eaves and Gables

Fit the top ventilation profile and finishing-profile base before the final board. Keep 22mm clear above the board and maintain at least 22mm between the cladding face and any drip edge.

Corners

Fix the Woodland internal or external aluminium corner base to the 70mm-wide corner battens. Leave 8mm at each board end, then fit the cover as stated in the current trim instruction.

Step 5: Finishing and Checks

Final Checks

  • Check every concealed fixing reaches a batten and every board end is supported
  • Check 8mm movement allowance remains at every board end and joint
  • Confirm the 22mm top and bottom ventilation paths are open
  • Remove swarf, dust and protective marks from the face of the boards
  • Confirm flashings, collars and trims discharge water without blocking cavity drainage

Do Not

  • Do not block required ventilation paths
  • Do not adhesive-fix boards directly to the substrate
  • Do not force boards tightly into trims or omit the 8mm movement allowance
  • Do not mix board colours or batches without checking the visual match first
  • Do not use abrasive cleaners on the embossed timber-effect surface
  • Do not install damaged boards or trims

Coverage Guide

Board Length Board Width Coverage Allowance
5000mm 333mm 1.665m² per board Add 10–15% for cuts and waste

For elevations with several openings, corners or mitred trim details, allow extra boards and trims before starting work.

Cleaning & Maintenance

Do

Wash with warm water, mild detergent and a soft cloth or sponge.

Occasionally

Check trims, fixings, sealant and ventilation openings as part of normal exterior maintenance.

Don't

Do not use solvents, bleach, abrasive pads or pressure washing close to trims and joints.

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