The ins and outs of Western Red Cedar
Building Centre Wood Talks
Footprint recently attended the Western Red Cedar Export Association’s Wood Talk presented by Patrick Cooper of Canada Wood UK.
A group of around thirty five gathered for a presentation on western red cedar, a lightweight timber that grows on the western coast of Canada. Cooper’s talk covered a wide range of technical issues including forest management and certification, life cycle analysis, product grades and specification, before concluding with installation information.
Early applications of western red by indigenous peoples included totem poles and canoes, because of its exterior durability and workability. The trees themselves can reach 40-60m in height and can measure 2.4m in diameter.
Over 90% of Canada’s forest land is publicly-owned and around 158 million acres are independently certified to the FSC/PEFC management schemes. The number of trees available for harvest is calculated from the gross yield of the total forested stock, with it being mandatory to re-plant like with like.
Felled trees are extracted by truck or by helicopter, to reduce the risk of erosion and loss of habitat. Due to the expense of harvesting makes it especially important that every wood chip is used, with local applications including heating the sawmill.
The acidity of western red (pH’s have been measured as low as 3.5) requires all fixings used to be stainless steel.
Coating is not necessary for this timber, but it can contribute to appearance and colour management. If covering, all six sides of the wood need painting to prevent moisture gradients occurring.
Although red/brown when freshly felled, untreated timber can weather to grey, or darker. Common inconsistencies in the weathering of the wood can include drip stains, which can be avoided by using coatings and removed using oxalic acid, though it is better to detail thoroughly first.
Western red is used extensively for cladding and other outdoor applications such as decking.
Cooper went onto present a series of international projects which have made innovative use of Western Red Cedar. Footprint’s pick is below:
Hopkins Architects’ Velodrome, whose cladding consists of 5000 m² of custom-cut western red cedar shiplap boards, chose the timber for its durability and outward expression of the material character of the wooden cycling track.
The timber is protected by the angle of the facade which protects the timber from the majority of precipitation, followed by a coat of Textrol Oil which prevents any absorption of rainwater.
R-List #2 Clear grade, 100% PEFC-certified
size 18mm x 140mm shiplapped boards, fixed grade 316 stainless steel nails and screws
Finish: Textrol Oil
Het Entreehuis, Hardenberg, The Netherlands
Completed in 2009, this 10-unit housing project by Bureau B+B Stedebouw en Landschapsarchitectuur occupies the grounds of an 800-hectare country estate. The development references vernacular relationships between buildings in traditional farmsteads.
The pilot home Het Entreehuis consists of a domestic building (pictured) and adjacent farm merging into a long, thin strip due to the use of the dark cladding: a black stained vertical and horizontal western red cedar siding.
Vertical and horizontal siding in a variety of sizes and profiles, face fixed with stainless steel nails and screws
Finish: anthracite coloured, oil-based resin
Bernal Park Support Building, Pleasanton, California, USA
This support building is one of several small amenity facilities designed as part of the 50 acre redevelopment of Bernal Community Park during 2010. Architectural elements include two concession buildings, two shade structures, a restroom and storage building to support the baseball program.
Mark Cavahnero Architects’ designed the façade using 1x6 horisontal tongue and groove western red cedar siding coated with a semi-transparent stain and graffiti coating. The horisontal band of glass panels allow for light and natural ventilation to penetrate the interior, while the wrapping corner windows provide unobstructed views of the games, giving the roof a floating appearance.
Vertical grain western red cedar, 1x6 tongue and groove, with blind nailing and SS 316 face nailing
Finish: water-based acrylic sealer, white semi-transparent stain and anti-graffiti coating