Timber technologies

Although the building was located in ‘Scots pine country’, a number of practical restraints and durability issues prevented its use. These included time constraints for kiln drying, ‘blue staining’ and ‘shakes’, and the need to reduce long-term maintenance costs by avoiding the use of pesticides or paint stains.

Douglas fir was therefore used for the external columns and Scots pine for the internal structure. The structure was designed as an internal forest of stylised trees with a central column and 150mm diameter poles set at a 60 degree angle to the horizontal, spreading like branches from the crown of the column.

The cladding is home-grown, untreated, European larch heartwood with stainless steel fixings to create a clean crisp appearance to the solid portions of the facade.

The secondary structure of wall studs and roof purlins are imported spruce flanges and OSB (Oriented Strand Board) webs made from home-grown timber, allowing an increase in depth of insulation. The windows are imported from Norway but, given the geographic location of the site, this is a lower transportation distance than sourcing windows from southern England.

Special timber-related features

The Forestry Commission’s ethos is to minimise the use of materials that are energy-intensive in their manufacture such as steel and concrete, and to maximise the use of sustainable and environmentally friendly natural materials such as home-grown timber.

Only the best quality locally sourced timber was used to provide good design and long term durability. The versatility of timber and the limited palette of materials minimised site waste, as off-cuts were used as ‘packers’ and ‘noggings’ thus reducing construction costs.

By not using paints or harmful chemicals, future treatment costs and the risks of producing any hazardous waste at the end of the building’s useful life were reduced.

Sub-contractors were selected with specialist knowledge of biomass heating and underfloor heating systems, rainwater re-cycling and water saving techniques.

Background to building

This new accommodation was designed to replace seriously inadequate 1970s timber drying sheds built on the site of a former sawmill which had been converted to offices. Cost restraints prevented its entire demolition, so a modern, attractive extension to the existing accommodation was commissioned, which would also meet the Scottish Government’s sustainable construction targets.

The building was designed to be an exemplar building and a modern working environment, where the cost-effective use of local timber and timber products in unorthodox and innovative ways was paramount.

The building provides open plan office accommodation, meeting rooms, staff facilities, storage and parking for the diverse functions of the Forestry Commission Scotland.