TG&V Interior Lining – Gesso Coated & Pre-Primed Timber
SPECIFIER AND INSTALLER GUIDE
Product Description
EziTrimplus pre-primed TG&V interior lining is manufactured from plantation-grown radiata pine, precision machined to a tongue, groove and V-joint profile to provide a consistent shadow line and high-quality paint finish. The product is factory gesso-coated and pre-primed with an interior-grade coating system and is designed for use in internal wall and ceiling applications within dry, controlled environments.
The lining is available in four standard sizes:
• 83mm cover × 10mm thick
• 83mm cover × 18mm thick
• 128mm cover × 10mm thick
• 128mm cover × 18mm thick
Profiles are produced from kiln-dried, finger-jointed radiata pine to ensure stability, uniformity, and reliable installation performance.
Compliance & Standards
Installation and performance should comply with the relevant provisions of the New Zealand Building Code. This includes structural fixing in accordance with NZS 3604, internal moisture management requirements under NZBC Clause E3, and fire performance requirements under NZBC Clause C where applicable to the building use.
Applications
This product is suitable for a range of interior applications including feature walls, decorative linings, ceilings in residential and light commercial buildings, and general architectural detailing. It is appropriate for both renovation and new build projects.
The lining is not suitable for soffits or any external applications, as soffits are classified as exterior exposure conditions and require systems designed for weather resistance.
Product Characteristics
The lining consists of finger-jointed radiata pine with a factoryapplied coating system, designed to accept a wide range of interior paint finishes including acrylic and enamel systems. The TG&V profile provides a consistent and repeatable installation with concealed fixing capability. When correctly installed, the system allows for natural timber movement associated with seasonal changes in moisture content.
Limitations
Timber is a natural material and will expand and contract in response to changes in humidity. Proper acclimatisation prior to installation is essential to minimise movement. Resin bleed may occur in radiata pine when exposed to elevated temperatures, and care should be taken in high heat or sun-exposed areas. Over-fixing or restricting movement may result in splitting, distortion, or surface defects. The product is not intended for structural bracing unless specifically engineered for that purpose.
Storage & Handling
All material must be stored flat and level on bearers spaced at a maximum of 1.5 metres, with a minimum clearance of 60mm above ground level. Packs should be kept dry, well ventilated, and protected from direct sunlight, moisture, and condensation at all times. Storage in newly enclosed or damp buildings, such as those with recently poured concrete or plastering, should be avoided due to elevated moisture levels. Other materials must not be stacked on top of the lining packs.
Acclimatisation
Prior to installation, the timber must be allowed to acclimatise to the final internal building conditions. This should occur with ventilation and, where applicable, mechanical heating or cooling systems in operation. The supplied moisture content is typically between 10 and 14 percent, and installation should not proceed where significant variation exists between boards. Installation should only commence once the material has stabilised in its service environment.
Substrate Requirements
Fixing should be to timber framing compliant with NZS 3604 or to ceiling battens as appropriate. For ceiling applications, linings are generally non-structural unless forming part of a diaphragm system. Ceiling battens are typically 70 × 35mm and installed at 400mm to 600mm centres depending on lining thickness. Battens must be securely fixed to rafters or ceiling joists and installed perpendicular to the supporting members.
For wall applications, linings should be fixed directly to studs at centres between 400mm and 600mm. Where boards are installed vertically, additional dwangs or nogs should be provided at maximum 400mm centres to ensure adequate fixing support.
Fixing Requirements
Fixing should be carried out using concealed fixing through the tongue wherever practical, with nails driven at an angle into framing members or battens. Only one fixing per framing member or batten is required. Boards should be installed so that subsequent boards fully conceal fixings.
Fixing may be completed using pneumatic or cordless finish nail guns, including angled or straight bradders. Angled bradders are generally preferred for concealed tongue fixing due to improved access, although straight bradders may also be used successfully.
Recommended fixing tools include:
Angled bradder
Paslode IM250A-Li 1.6mm Angled Bradder
Straight bradder
Paslode IM250S-Li 1.6–2.0mm Straight Bradder
For 10mm thick TG&V lining, concealed fixing through the tongue should generally be undertaken using 16G (1.6mm) brads between 40mm and 50mm length, providing approximately 25mm minimum penetration into framing.
Typical fixing options include:
• 40 × 1.6mm zinc plated brads (straight bradder)
• 45 × 1.6mm zinc plated brads (angled or straight bradder)
• 50 × 1.6mm zinc plated brads (angled or straight bradder)
For 18mm thick TG&V lining, concealed fixing should generally be undertaken using 50–63mm brads to achieve adequate embedment and holding performance. Both 16G (1.6mm) and 14G (2.0mm) brads may be used depending on fixing requirements and installer preference.
Typical fixing options include:
• 63 × 1.6mm zinc plated brads (angled bradder)
• 50 × 2.0mm galv brads (straight bradder)
• 62 × 2.0mm galv brads (straight bradder)
Fixings must not be placed within 20mm of board ends to minimise splitting risk. Care should be taken to avoid overfixing, which may restrict natural timber movement and lead to cracking, distortion, or surface defects.
Jointing & Sealing
Where profiles are joined, mitre cuts should be used where appropriate to achieve accurate alignment. All mitre joints must be made over framing or battens and glued using a PVA adhesive to ensure a tight and stable joint.
Finishing
Prior to painting, all surfaces must be clean, dry, and free from dust or contaminants. The factory primer should be checked to ensure it is sound and well bonded. Light sanding may be required to remove minor surface imperfections.
All exposed nail holes should be filled using a suitable acrylic interior filler compatible with pre-primed surfaces. Once cured, the filled areas should be lightly sanded smooth, typically using fine sandpaper minimum 180 grit. Care should be taken to avoid over-sanding, which may damage the primer. Spot prime sanded area where necessary.
Pre-primed profiles should receive two to three coats of interior acrylic or enamel paint in accordance with the paint manufacturer’s recommendations. Light-coloured finishes are preferred, as they reduce heat absorption and minimise movement-related stresses. Paint systems should be applied consistently to achieve uniform coverage and durability.
Resin Bleed
Radiata pine may exhibit resin bleed when exposed to elevated temperatures. This typically appears as amber or honey-coloured staining on the surface. If resin bleed occurs, it may be cleaned with mineral turpentine prior to curing, or scraped or sanded once crystallised. In some cases, the application of a stain-blocking primer may be required before repainting. Resin bleed may recur under sustained high temperatures.
A no-mar tip should be fitted to nail guns to minimise marking or crushing of the pre-primed surface during installation. Nail gun depth settings should be adjusted for each application to ensure fixings sit flush or only slightly recessed below the surface (typically no more than 1–1.5mm) to minimise filling and finishing work. Fixings must not be overdriven.
Construction adhesive may be used as an optional supplement to mechanical fixing to improve bonding and reduce movement stress. Suitable products include Sika Nailbond Premium or equivalent flexible adhesives, applied in accordance with manufacturer recommendations. Adhesive use is not mandatory and must not be relied upon as a substitute for mechanical fixing or used in a manner that restrains natural timber movement.
Health & Safety
Appropriate personal protective equipment must be worn during cutting, sanding, and installation, including eye protection, dust masks or respirators, and hearing protection where required. All power tools should be used in accordance with manufacturer safety guidelines, and care must be taken when handling sharp tools and fasteners. Work areas should be adequately ventilated.
Waste Disposal
Timber offcuts should be disposed of in accordance with local council requirements. Treated or painted timber waste must not be burned. Sawdust and waste materials should be managed responsibly to prevent environmental contamination.