ECOLOGICAL LONG-LASTING ATTRACTIVE

TEChNICAL dATA ShEET
1. Introduction
1.1 General
With the development of the DAUERHOLZ process, it has been possible
for the first time to modify indigenous wood in such a way that it exceeds
all other standard indigenous woods and even many tropical woods as
regards durability and dimensional stability in outdoor applications without
making any compromises in terms of strength. Full impregnation of
wood with non-toxic wax through to the core ensures very good hydrophobicity
(water-repellent impregnation) of the material. Combined with
the low equilibrium moisture content of DAUERHOLZ, the basis of life for
wood-destroying organisms (fungi, insects) is thereby eliminated.
1.2 The DAUERHOLZ manufacturing process
The basic material for the production of DAUERHOLZ is sawn timber from
native woods, especially Scotch pine. In accordance with a preconditioning
process exactly co-ordinated to the patented DAUERHOLZ process
followed by drying, the wood is impregnated with a liquid wax inside
an autoclave. This is followed by a defined post-conditioning process for
formulating the equilibrium moisture content and consistent wax distribution
inside the wood. The treated wood then runs through the usual
processing steps such as sawing, planing and profiling.
2. DAUERHOLZ features
2.1 DAUERHOLZ dimensional stability
The DAUERHOLZ process significantly reduces the equilibrium moisture
content. DAUERHOLZ is supplied with an average residual moisture of
approx. 10 %. Thanks to the considerable hydrophobicity (water-repellent
impregnation) of DAUERHOLZ, its swell and shrinkage properties
are significantly reduced. As indicated in Fig. 1, the water absorption
and therefore dimensional changes are reduced over the comparison
period by more than 60 % when compared to untreated wood. Accordingly,
DAUERHOLZ products do not display the deformations (splitting,
warping) typical of changes in wood moisture or only in minimum and
insignificant form.
Fig. 1: Results of an underwater swell test over 30 days
g/cm 3
0,25
0,2
0,15
0,1
0,05
0
Water absorption in g/cm³
0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31
Raw pine
DAUERHOLZ-pine
Test duration
in days
2.2 Laying DAUERHOLZ decking
DAUERHOLZ recommends proceeding as follows:
• 5 mm spacing between planks which are 90 or 115 mm wide, 6 mm
between planks which are 130 mm wide and 7 mm spacing between
planks which are 140 or 145 mm wide.
• The base should be laid with max. 40 cm (plank thickness = 21 mm),
max. 50 cm (25 mm) or max. 80 cm (42 mm) spacing.
• The screws must be made of stainless steel.
• All holes should be pre-bored and then countersunk.
• Decking should be laid at an incline of approx. 1% away from buildings
2.3 DAUERHOLZ durability
Following initial screening tests, DAUERHOLZ durability complies with
class 1 (very durable) in accordance with the EN 350-1 and EN 350-2
standards. DAUERHOLZ thereby achieves or even exceeds most tropical
woods in terms of durability, e.g. bangkirai. Even with permanent ground
contact or persistent water (hazard class 4), protection is provided
against wood-destroying organisms. This means that there are practically
no limits to the possible applications in outdoor areas.
2.4 DAUERHOLZ appearance and weathering resistance
The natural colour of DAUERHOLZ complies with that of untreated wood.
DAUERHOLZ PUR (unoiled surface) or, on request, DAUERHOLZ PLUS
with oiled surface are supplied ex works. Thanks to the DAUERSCHÖN +
wood oil used, the oiled variant is attributed an individual colour and additional
UV protection.
2.5 DAUERHOLZ hardness / strength
Depending on the density of the initial material, DAUERHOLZ pine has
an average density of 700 to 800 kg / m³. Laboratory tests have confirmed
that strength increases by up to 30 % (see Table 1) via full impregnation
with wax and when compared to untreated wood (compressive strength
longitudinal and transverse to grain direction). Average surface hardness
also increases by approx. 30 %. The strength losses often observed
in thermally-modified wood (so-called thermo-wood) do not affect
DAUERHOLZ at all.
Tab. 1: A comparison of strength values
Sample layer /
Source
Density
kg / m³
Compressive
strength
N / mm²
Radial
hardness
N / mm²
Tangential
hardness
N / mm²
End grain
hardness
N / mm²
Sapwood, close-ringed 960
DAUERHOLZ pine
86,2 39,8 31,6 143,5
Sapwood, broad-ringed 937 69,7 35,0 28,4 114,7
Core, close-ringed 669 75,2 22,8 18,7 87,5
Core, broad-ringed 617 56,8 21,2 16,6 80,4
Sapwood, closeringed,
40 ° C
Sapwood, closeringed,
untreated
949 – 34,1 – –
untreated pine
509 – 19,8 – –
DIN 68364 520 45 – – –
Kollmann 520 55 13…19…24 13…19…24 25…40…72
Sell 510…550 45…55 14…23 14…23 39…41
2.6 DAUERHOLZ flammability / fire performance
DAUERHOLZ has been tested as regards its fire performance values in accordance
with DIN 4102-1. Test results have established that DAUERHOLZ
complies with the requirements of building material class B2 and can be
regarded as having normal flammable properties. In the event of a fire,
DAUERHOLZ can be extinguished using all standard fire extinguishing
agents, albeit preferably powder or foam.
2.7 DAUERHOLZ non-slip properties
Patio decking made of DAUERHOLZ has been tested to DIN 51130 (working
areas with increased risk of slipping) and DIN 51097 (wet barefoot areas)
in terms of its non-slip properties. On the basis of the test results obtained,
DAUERHOLZ flooring can be allocated to evaluation groups R 11 to R 12
in accordance with the specifications outlined in DIN 51130 and evaluation
groups B to C as per DIN 51097 as well as displacement class V6.