EN 350-2: 1994

Durability of Wood and Wood-based Products – Natural Durability of Solid Wood: Guide to natural durability and treatability of selected wood species of importance in Europe

This lists the natural durability of solid wood for selected species considered of importance to the European countries for use as constructional purposes.  It provides their relative durability to wood-destroying fungi, dry wood-destroying beetles, termites and marine organisms. It also gives information relating to their treatability, origin, density and sapwood width.

While part two does not give service lives for components, it ranks various wood species in order to compare unknown species with well-known ones.

Classification of the natural durability of wood-destroying fungi                                                

Durability Class

 Description

1

Very durable

2

Durable

3

Moderately durable

4

Slightly durable

5

Not durable

Classification of the natural durability to beetles

 Durability Class

 Description

D

Durable

S

Susceptible
Note:Beetles = Hylotrupes bajulus, Anobium punctatum, Lyctus brunneus and Hesperophanes cinnereus

Classification for the natural durability to termites and marine borers

 Durability Class

 Description

D

Durable

M

Moderately durable

S

Susceptible

Classification of the treatability of wood

 Treatability Class

 Description1

Explanation

1

Easy to treat Easy to treat; sawn timber can be treat penetrated completely by pressure treatment without difficulty

2

Moderately easy to treat Fairly easy to treat; usually complete penetration is not possible, but after 2 h or 3 h by pressure treatment more than 6 mm lateral penetration can be reached in softwoods and in hardwoods a large proportion of the vessels will be pentrarted

3

Difficult to treat Difficult to treat; 3 h to 4 h by pressure treatment may not result in more than 3 mm to 6 mm lateral penetration

4

Extremely difficult to treat Virtually impervious to treatment; little presevartive absorbed even after 3 h to 4 h by pressure treatment; both lateral and longitudinal penetration minimal
Notes:
1 Historically treatability data may use other descriptive terms to approximate the treatability class.  Class 1: Permeable; Class 2: Moderately resistant; Class 3: Resistant; Class 4: Extremely resistant.