Timber Construction

Manufactured Wood Products
Blockboard and Laminated Board
Blockboard and laminated board
DIN 68705-2
Thermal conductivity:
>v,, = 0.15W/mK
Vapour diffusion resistance factor:
H = 50/400
Raw density:
p = 400-800 kg/m 3
Computation weight in accordance with
DIN 1055-1:
4.5-6.5 kN/m 3
Building material classification:
B2
Material class:
20, 100
Emission class:
E1
Wood moisture content;
5< 15%
Amount of swelling and shrinkage
per % change in wood moisture content:
0.020 %
Wood species:
• spruce
•fir
• pine
Dimensions
Thickness [mm]:
13, 16, 19,22,25,28,30,38
Length [mm]:
1,220, 1,530, 1,830.2,050,2.500.4,100
Width [mm]:
2.440. 2,500, 3,500, 5,100, 5,200. 5,400
Material
Formerly known as core plywood, blockboard
consists of a core layer of solid
wood board-shaped strips that are glued
together. The width of the strips varies
from approx. 24 mm to a maximum of
30 mm. A face veneer (three-ply board)
or a cross-band veneer and a face
veneer (five-ply board) is fixed to each
side, with the grain running perpendicular
to that of the adjacent layer.
Laminated boards are composed of a
middle core of perpendicular rotary-cut
veneers (strips) that are glued together.
The veneers are 5-8 mm thick. A face
veneer, or a cross-band veneer and a
face veneer, are fixed to each side. The
grain of each sheet runs perpendicular to
that of the adjacent one.
All glues with an assured adhesive
strength are permissible.
In the case of blockboard. the glued
wooden core is composed of softwoods
(primarily spruce) to ensure a more stable
form, whereas softer or harder hardwoods
are generally chosen for cross-band
veneers and face veneers.
The same wood species can be used for
both wooden core and veneer plywood,
alongside the customary indigenous softwoods
and hardwoods. A number of
tropical woods are also used for the cores
and for cross-band and face veneers,
rounding off the customary indigenous
softwoods and hardwoods available.
Use
Blockboards and laminated boards are
primarily used in the manufacture of furniture,
as well as in laboratory and stair
construction. However, they are rarely
used in timber engineering.
For invitations to tender and orders:
• Manufacturer
•DIN
• Panel type
• Wood species
• Emission class
• Thickness
• Width
• Length
• Surface
Calculated by m 2
Manufacture
In general, 24 mm-thick softwood boards
that have been carefully dried to a wood
moisture content of approx. 6-8 per cent
are considered suitable for the manufacture
of block cores. These boards are cut
into laths with multi-blade circular saws
so that the lath width corresponds to the
thickness of the inner core. The laths are
then glued together with casein, polyvinylacetate
or urea-formaldehyde resins
to form boards and pressed.
DIN 68705-4 refers to structural blockboard
and core-stripe blockboard as
plywoods with defined, monitored elastomechanical
properties. They are used in
building construction (e.g. for reinforcement).
In the manufacture of the core, rotary cut
veneers 5-8 mm thick are glued in layers
parallel to the grain to create blocks.
These are then sawn at right angles to the
level of the single plies to make boards.
In both manufacturing processes, the
cross-band and face veneers are glued
to the inner plies with the same glues and
pressed.
Manufactures) (selection)
Pfleiderer
Three- and Five-Ply Panels
German building authority certification:
Z-9.1-242
2-9.1-258
Z-9.1-376
Z-9.1-404
Z-9.1-477
Thermal conductivity:
= 0.14 W/mK
Vapour diffusion resistance factor:
11 = 50/400
Raw density:
p = 400-500 kg/m 3
Building material classification:
B2
Material class:
20,100, 100G
Emission class:
E1
Wood moisture content:
12 ± 2 %
lount of swelling and shrinkage
per % change in wood moisture
content:
0.020 %
Wood species:
spruce
larch
i* Douglas fir
.-••nensions
iThickness (three-ply) [mm]:
^12-75
hickness (five-ply) [mm]:
33-80
[Length [mm];
_ 2,500-6,000
i [mm]:
1,000-4,750
Material
The panels consist of three or five layers
of softwood, each glued at right angles to
the adjacent ply. Melamine modified
urea-formaldehyde and phenolic resin are
used as glues.
Since the thicknesses of the single plies
vary according to type and manufacturer.
the elasto-mechanical properties of panels
of equal thickness can also differ considerably.
Applications)
Depending on glue type and the wood
preservative (if any), the panels can be
employed wherever panels of wood
classes 20, 100 and 100 G are allowed
under both the German Building Regulations
and DIN 68800-2.
Once permission has been granted, the
multi-ply panels can be used as effective
and as reinforcing planking in manufacturing
wall, ceiling and roof panels for
wooden houses that are erected as panel
construction systems in accordance with
DIN 1052-3.
Depending on the type of permit granted,
these panels can sometimes be used in
place of laminated construction board as
per DIN 1052-1.
If the edges are carefully covered or
sealed for protection, they can also be
used for large ventilated facades.
Manufactured Wood Products
Three- and Five-Ply Panels
Invitations to tender and orders:
• Manufacturer
• Certification number
• Panel type
• Wood species
• Wood preservation measures
• Thickness
• Width
• Length
• Surface
Calculated per m 2
Manufacture
In the case of softwood plies glued at
right angles to one another, at least 90
per cent of the single sheets must be
grade S10 (DIN 4074-1) and the remaining
sheets at least grade S7.
The surface veneers must be at least
4-9 mm thick, and those oi the inner
plies 4-50 mm.
Manufacturer(s) (selection)
Dold Suddeutsche Sperrholzwerke
Gmach Holzbauwerke
Haas Fertigbau GmbH
Kaufmann Holzbauwerk
Probstel Holzwerke
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