| Spruce |
B – visible |
C – not visible |
| General Requirements
|
perfect gluing,
no open joints
|
perfect gluing
|
Structure, grain direction,
figuring
|
strong timber structure
and slight spiral grain permissible, vertical or horizontal annual
growth rings |
no special requirements |
Knottiness
|
healthy firmly intergrown
branches and isolated black knots permissible |
no special requirements |
Loose knots |
permissible, max. 3/panel
max. ø 10 mm |
no special requirements |
Circular plugs |
permissible, max. 3/m2,
no in-line configuration |
no special requirements |
Resin galls |
low-resin, large resin galls
patched with boat plugs |
no special requirements |
Bark pockets |
permissible if isolated |
no special requirements |
Cracks
|
slight surface cracks permissible
if isolated, penetrative end cracks permissible up to 50 mm long
if isolated |
no special requirements |
Heart centre |
permissible |
no special requirements |
Compression wood
|
permissible |
no special requirements |
| Insect attack, worm-holes |
inadmissible |
Insect attack inadmissible,
worm-holes permissible if isolated |
Discolouration, fungal attack
|
isolated occurrences of slight
discolouration permissible (e.g. blue stain) |
no special requirements,
rot inadmissible
|
Surface condition |
isolated small faults permissible |
no special requirements |
Mixing of wood types |
inadmissible |
inadmissible |
|
|
|
| Larch |
B - visible |
C - not visible |
Similar to spruce (see above)
except for the following: |
small proportion of sapwood
possible, more black knots, more patched areas on a case by case
basis |
unplugged, insofar as no
fire protection class is required and the static properties are
not impaired |
