Air Dried Oak Tongue and Groove External Cladding

Our Air Dried Oak Tongue and Groove External Cladding is tongue and groove cladding in European oak, for external use.

About European oak

Air dried (seasoned) European oak, more stable and less prone to shrinkage than fresh sawn oak.

The boards are air dried outside for approximately 6 months, to between 16% and 25% moisture content.

Characterful boards that may show a small amount of sap on the underside, sound knots without limitation and occasional historic insect damage.

Supplied untreated.

Left alone it weathers to silver grey.

Profile and fitting

Boards fix together by inserting the tongue into the groove. They can be fitted horizontally or vertically; fit horizontal boards tongue uppermost so moisture runs off. Tongue 12 × 8 mm (Martyn long-tongue) on all sizes — not the old website short-tongue 5 × 4. Plan geometry is Martyn ×20 on both 20 mm and 24 mm thicknesses (same approach as shiplap ×24).

Grades and options

• First Grade: mostly clear of knots, with some knots up to 5 mm allowed and a small amount of sap on the underside only.
• Character Grade: sound knots without limitation, sap and occasional historic insect damage.
• End matching (tongue and groove on the board ends) lets you place joints where they fall rather than on a batten, which speeds up fitting and reduces wastage.

Sizes and pricing

• 120 x 20 mm (visible face 108 mm; tongue 12 × 8 mm): from £46.99 per m² ex VAT
• 142 x 20 mm (visible face 130 mm; tongue 12 × 8 mm): from £56.99 per m² ex VAT
• 120 x 24 mm (visible face 108 mm; tongue 12 × 8 mm): from £58.99 per m² ex VAT
• 142 x 24 mm (visible face 130 mm; tongue 12 × 8 mm): from £71.49 per m² ex VAT
• Supplied in random lengths between 1200 mm and 3600 mm.
• Set lengths are available for an extra charge using Set lengths (Cladding): surcharge £8.00 per m² ex VAT up to 3500 mm, £12.00 per m² ex VAT above 3500 mm. Add the same number of m² of set lengths as cladding.

Specifications

Finishing and aftercare

Supplied untreated. No treatment is needed, but to hold the colour for longer or add a weather-resistant finish, see our cladding treatments.

Drawings and downloads

Tap the drawing to open it full size.

Tap the drawing to open it full size.

Good to know

• Use stainless steel fixings only. This is essential for oak: its tannin reacts with ordinary steel fixings and causes dark staining.
• Natural timber varies: expect some differences in colour and grain from board to board and from the photos.
• Boards left exposed to changing weather before fitting are likely to cup, warp and split. We suggest fitting between October and April where possible, within 7 to 14 days of delivery.
• Sizes are nominal and can vary slightly with moisture content.
• Not sure? Order up to two cladding samples first.
• Questions? Please contact our Sales Team on 01536 267107.