Boarded refers to a construction that has been clad or covered with planks or boards. The term is most commonly used in traditional timber construction, particularly for roof structures, but also applies to walls, ceilings, and facades. When a structure is described as “boarded,” wooden planks have been fixed to the structural frame to create a closed surface.
Boarded roof
The most common application is the boarded roof. In a boarded roof, timber planks (known as roof boarding or sarking) are nailed to the underside or topside of the rafters or purlins to form a continuous surface. This boarding serves several important functions:
- Substrate for roofing materials — the boards provide a flat, stable base for tiles, slates, felt, or other roof coverings
- Thermal performance — the closed surface prevents drafts and, when combined with modern insulation materials, significantly improves energy efficiency
- Finished ceiling — on the interior side, the boarding creates a visible ceiling surface, which is particularly desirable in loft conversions and attic rooms
- Bracing — the boards contribute to the overall rigidity of the roof structure by distributing forces across multiple rafters
Materials and execution
Traditionally, softwoods such as spruce or pine are used for roof boarding, typically in thicknesses of 18-22 mm. The boards are joined using tongue-and-groove connections to create a windtight surface. In modern construction, plywood, OSB (oriented strand board), or MDF panels are also used as boarding, depending on the requirements for strength, moisture resistance, and appearance.
In heritage buildings and historic barns, the original boarding is often still intact and is considered a characteristic architectural feature. During renovation projects, existing boarding is preserved where possible or replaced in a sympathetic style.
Related terms
- Sarking
- Rafters
- Purlins
- Tongue and groove
- Sheathing
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