About American Douglas Fir

Co2 Douglas Fir ® about
American Douglas Fir is a imported softwood Timber from North American. A sustainable timber with good workability and moderate durability, please see below. It has a density 620 lbf (2,760 N) on the Janka Hardness scale. Our Co2 Douglas Fir is PEFC. PEFC Programme for the Endorsement of Forest is a world wide umbrella organization endorsing a national forest certification systems. We supply top grade being "85% Number 2 clear 15% number 3", which gives a small knot content.

Widely used in the construction industry, from structural work to cladding (internal and external), decking, fencing and the boating industry. The scientific name is Pseudotsuga menziesii and is sometimes used as Christmas trees in North America. Light brown colour with a hint of red and/or yellow, with darker growth rings, but as with all timber there are a number of variations from tree to tree.

A durability Class 3 (moderate) rating (BS EN 350-3 classes) meaning it can be left untreated to age naturally if desired. But will happy "take a stain" or good quality wood treatment please see our accessories for a range of products.

It's considered to be a real "all rounder" great for external cladding, landscaping projects, decking, garden offices/building etc.. Within the house building industry it is used for internal/external structure, mouldings, flooring etc.. Used as a veneer and in plywood as it is stiff and strong for its weight.


When selecting your timber type for your project it is worth taking in to consideration BS EN 350 timber durability class.

Durability is the ability of a species to resist decay either naturally or through preservatives. The Class is based on the ability of the heartwood (inner part of the tree) to resist fungal decay. The sapwood (the living outermost portion of the tree)is considered not durable and should not be used for external projects without preservative.

BS EN 350 has 5 classes of durability they are:-

Class 1 to 3 can be left as untreated timber, a natural ageing process will accrue e.g. Larch will turn a grey colour. Class 4 and 5 will need to be treated with preservatives.

For further information see www.greenspec.co.uk/building-design/cladding-durability-quality