Service & Support > Technical files
General Technical Questions Answered
GRANORTE 2009
version: 2009.02 | date: 16-09-2009
For technical questions, please visit our Service & Support page on our site at www.granorte.pt where you can
download some technical documents (we are posting regularly new versions and new documents). However,
please find below some short information to refresh your knowledge about cork coverings.
BINDERS
All our products use a polyurethane pre-polymer as binding agent of the granules and pieces of
cork. This is a top quality binder, as it maintains the characteristics of the agglomerated cork very
similar to the ones we could expect on natural plain cork. This is a secure binder too, as it has no
toxicology, no formaldehyde and no VOC content.
The raw materials used for the production of the binder are described in the FDA list and/or the
regulation 90/128/CEE (with its modifications) of materials that can be used in contact with food.
Studies have demonstrated that after reaction the binder is transformed into a polymer which is
completely free of isocyanate groups and, thus, is free of any toxicity.
AGGLOMERATED CORK
When you make a composition agglomerated cork, you add some binder (glue) to the cork and
than press the mixture. The binder will cure (harden) and agglomerate all the cork granules
together. To accelerate this process a catalyst can be used. In this case the catalyst is the
temperature. As you know, cork is a natural thermal insulator. So, on a traditional process there is
a substantial quantity of heat that is has to be used (100-120 ºC for 8-12 hours). The highfrequency method works like a microwave. It is more efficient because the high frequency makes
the water molecules vibrate and produce heat even in the interior of the mixture. So we need less
temperature and less time.
Regarding “black boards” (black insulation cork), they are obtained without any added binder. The
cork granules are heated at high temperature and pressure (autoclave) so that the resin of the cork
itself can do the agglomeration. Due to the heat, the grains become dark and expand. That is why
this kind of material is known as “pure expanded agglomerated cork”.
THICKNESS OF CORK VENEER
Thickness of cork veneers depends, of course, on the type of the cork covering. However, we can
say that it is normally between 0.6 mm and 1 mm.
DENSITY OF CORK
3
Density of cork floorings is normally divided in 3 categories: low-density 400-450 Kg/m , medium3
3
density 450-500 Kg/m and high-density 500 Kg/m and above. The choice of the right density for a
cork floor covering has to be made taking into attention the level of use, the type of floor and the
type of finishing.
For press-cork sheets (underlayment) the density can vary according to the type and application.
3
However, typical values are around 180-220 Kg/m .
FINISHES
Floorings from GRANORTE can be delivered unfinished (natural) of coated with a wide range of
finishes:
- UV cured acrylic/urethane “MAT”;
- UV cured scratch resistant WEARTOP “WT”;
- UV cured anti-slip, high-abrasion and scratch resistant WEARTOP ARMOUR “WTAX”;
- UV cured hard-oil “CEROL”;
- Waterbased hard-wax “CERAQ”;
- One component waterbased PU/acrylic lacquer “AQUA”;
- Two components waterbased PU lacquer “AQUA2K”.
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Service & Support > Technical files
General Technical Questions Answered
GRANORTE 2009
version: 2009.02 | date: 16-09-2009
U.V. CURED URETHANE VARNISH
This product is a urethane-acrylic based UV cured finish system. The main component is a
urethane resin that will react with the acrylic monomers, at the time of curing by ultraviolet
radiation, forming a strong chain of repeating units, or "polyurethane". So, in the end of the reaction
we have a polyurethane coat. Furthermore, due to the photoreaction of the UV radiation, the UV
cured varnish can be more resistant to wear and chemicals than the air-dried waterbased ones.
UV CURED SCRATCH RESISTANT WEARTOP
Using new, state-of-the-art resins which are extremely elastic and advanced nanoparticle
technology, WEARTOP finish offers unprecedented performance and an outstanding appearance.
Coating hardness and abrasion resistance are not achieved at the expense of flexibility.
Furthermore, WEARTOP offers optimal micro-scratch resistance. Rubbing the surface with steel
wool has negligible effect and no black marks are formed when the surface is scratched with a
metal object. The resistance to scratches and sanding marks caused by hard dirt particles and
sand is remarkably high, making WEARTOP the perfect coating for our everyday needs.
In contrast to anti-abrasive top coats with ceramic/aluminium oxide, WEARTOP can be sanded and
is therefore easy to re-coat. The optimal balance provided by WEARTOP allows the cork floorings
to continue to be easily cleaned and maintained. Furthermore, due to the advanced nanoparticle
technology, the cork surface will have an outstanding appearance: smooth, warm, deep-clear and
natural.
One major ecological benefit of WEARTOP is that only reactive products are used: this means that
it is solvent free and especially environmental friendly. There is no organic solvents and no VOC
emission during processing, facilitating compliance with stringent environmental regulations.
UV CURED ABRASION AND SCRATCH RESISTANT WEARTOP ARMOUR
Using the same philosophy as WEARTOP, coating hardness and abrasion resistance are not
achieved at the expense of flexibility. Advanced micro and nanoparticle technologies are used
together to achieve unprecedented wear and scratch resistance performance.
The multi-layer finishing system of WEARTOP ARMOUR combines extremely elastic coats with an
“armour” micro ceramic compound coat and a “nano” topcoat. It is the innovative integration of the
different layers that makes the final product exceptional in both performance and appearance.
In fact, WEARTOP ARMOUR outperforms any other finish for cork coverings in either resistance to
wear, impact resistance, scratch resistance or chemical resistance. Furthermore, due to the
advanced nanoparticle technology, the cork surface will have the same outstanding appearance
(smooth, warm, deep-clear and natural) already recognised in WEARTOP.
WEARTOP ARMOUR is completely staining resistant trough its higher chemical resistance.
HARD-OIL
It is a UV-hardened Wax-Oil finish, based on natural and environment friendly products. It gives
cork floorings a good protection to wear, keeping it easy to care and maintain. The natural warm
touch and beauty of cork is enhanced by the softness of this oil finish.
WATERBASED HARD-WAX
It is the ultimate wax finish for floors. It was developed to replace the standard solid or hot melt
waxes that look nice but are always difficult to clean and maintain. It has an attractive natural
smooth look-and-feel and a good wear and chemical resistance.
WATERBASED LACQUER
It is a water diluted one-component PUR multi-layer coating system for cork floorings. The airdrying one-component waterbased system provides excellent abrasion properties and highest
yellowing resistance once only reached by 2 Component systems. “AQUA” coating provides a silky
matt finish and has a higher resistance against chemical agents than those of conventional
waterbased lacquers, throughout the final UV-hardening. It’s easy to maintain trough common
maintenance products, has no residual odour and keeps cork with its natural look-and-feel.
WATERBASED 2 COMPONENTS PU LACQUER
Probably, the most advanced waterbased factory-applied finish for cork. It is a two-component PUR
waterborne multi-layer coating system. The most remarkable features of “AQUA2K” are the very
high abrasion resistance, good compromise between hardness and elasticity and the very high
chemical resistance of a two component product. It’s easy to maintain with common maintenance
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Service & Support > Technical files
General Technical Questions Answered
GRANORTE 2009
version: 2009.02 | date: 16-09-2009
products, has no residual odour and keeps cork with its natural touch. Due to its excellent lightfastness, this finish is especially suited for use on coloured cork flooring.
A common characteristic of all these finishes is that they all are environmentally friendly, have
negligible VOC content and are free of heavy metal, formaldehyde and insecticides/pesticides.
VARNISHING and REFURBISHING
We recommend that cork floor tiles should be varnished after installation (sealing of joints and
improving wear resistance). Always varnish with a specially recommended cork varnish. It is
essential to follow the varnishing instructions of your supplier strictly. Apply 3 coats of varnish (one
coat is enough for pre-varnished cork floor tiles). On pre-varnished floors, it is recommended to
sand slightly before applying the first coat with fine sandpaper (e.g. grain 240), and then vacuum.
All varnished floors need refurbishment depending on the intensity of use. When refurbishing, sand
the old varnish carefully and remove wax, maintenance products, dirt, etc. Remove the dust by
vacuuming and apply 2 coats of varnish. The varnish has to be a “for cork” one and preferentially
waterbased.
WEARTOP
We are sure that WEARTOP finish is bringing a REAL innovation to cork floorings. All the
disadvantages of ceramic/aluminium oxide are not present at WEARTOP. So, the warm soft touch
of cork is still there and the deep-clear beauty of cork is still seen. None of these (even closer) you
will see on the "new" finishes from the competition. ALL of them use aluminium oxide particles for
enhancing the scratch and wear resistance. In fact, the use of ceramic/corundum particles is
already an “outdated” technology than can make some sense in some hard floors, but it makes no
sense in a NATURAL RESILIENT product like CORK.
Unlike everyone else, we have not valued the “disposable-hard-cold-rough-seems-like-laminate”
feature on a cork floor. We have chosen the “maintainable-warm-smooth-you-can-let-your-childplay-on-the-floor-with-bare-feet” philosophy.
And how is this being accomplished by WEARTOP? You can understand that we cannot give you
details, but the essential is on our WEARTOP information.
COLOR DIFFERENCES
Cork, as all natural products, has many different qualities, types and shades. In spite of all the care
and control made during the production, these differences are maintained on finished cork
coverings. This is an inherent characteristic of cork tiles, and part of its natural beauty. Always
verify this by daylight before you start laying the floor. Proceeding in this manner, you can distribute
the tiles in such a way that variations in structure and/or shade are not striking
UV LIGHT RESISTANCE
All natural products are affected by UV (sun light). Cork has a natural tendency to discolour. It is
difficult to use UV filters as cork fades under an UV light wavelength very close to the wavelength
of visible light. This means that the filter, to be effective, will not be transparent. That is one reason
why coloured cork floors are more light resistant than the natural ones. GRANORTE applies
finishes that are very resistant to UV radiation and that give protection to the natural discoloration
of cork.
INDENTATION
Resilience is a natural characteristic of cork. So, cork coverings have a natural capacity to
recuperate after static load. On a floor covering, there are some factors that can change this
capacity (thickness, density, type, varnish…), however, a recuperation of about 90% should be
expected and the residual indentation is (normally) below 0.2 mm.
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Service & Support > Technical files
General Technical Questions Answered
GRANORTE 2009
version: 2009.02 | date: 16-09-2009
RESISTANCE OF FLOATING FLOORS TO WATER
GFIX cork floating floors are based on pre-treated, watertight HDF board. Furthermore, the edges
of the panels are factory protected with the “JointShield” technology. Nevertheless, wet mopping
should be avoided and spills or any excess of water should be cleaned as soon as possible.
The combination of “JointShield” impregnated joint and the high moisture resistant HDF core
makes GRANORTE’s cork floating floors the most durable in the industry.
CASTOR CHAIRS
The concern about the effect of castor chairs makes sense, but not only on a cork floor. In fact,
how long will any kind of flooring remain attractive under the heavy wear and tear of office castor
chairs use? There are many cork installations on these conditions but, of course, protecting
measures should be taken if you want your floor to last. So, further to the traditional caring
measures like:
- Use of walk-off mats at entrance doors;
- Eliminate particles of dirt/grit;
- Vacuum or sweep as needed;
- Install proper protectors under “feet” of furniture;
- Periodically check floor for signs of wear;
On an office environment we recommend:
- Extra 2 layers of a PU 2 component varnish after installation;
- Use of wide casters on caster wheeled chairs;
- Use of a protective PVC mat under office chairs.
Plus, the cork floorings for commercial use are different than the ones for residential areas.
The bottom line is that regarding wear, cork can be treated like a wood floor: If it will damage a
wood floor, then it will damage cork.
WHY FLOOR CARING?
The formation of scratches is a natural process independent on the type of flooring. Thus sooner or
later the entire flooring must be worked over or replaced completely. The duration until such
measures has to be taken depend on some factors:
- Wear intensity (domestic or public areas);
- Type of shoes that normally walk the floor;
- Quantity of dirt brought onto the floor;
- Kind of dirt brought in;
- How often (and how effective) is the floor being cleaned.
The type of flooring which has been used or the type of surface, respectively, has a major
influence. Moreover it is not necessarily an advantage to have an extra hard surface (e.g. laminate)
since hardness often also means brittleness. Elastic coatings are possibly able to resist heavy wear
much better.
So first of all a floor can be protected by keeping the mechanical stresses as little as possible.
Wearing shoes with soft soles contribute to this aim as well as avoiding bringing in dirt (by using
special cleaning mats in the entrance areas) and cleaning the floor regularly and thoroughly.
Additionally, a caring method should be established. A special floor care product is applied and
uniformly distributed. After drying a thin film is obtained which serves as a sacrificial layer. This
layer will be slowly worn off by using the floor. The advantages of this method are:
- Excellent protection of the flooring against slight and medium mechanical stresses;
- Simplification of cleaning procedures by generating a smooth surface;
- The caring procedure can be repeated some times to renew the protective layer. Hereby
smaller scratches will be equalized resulting in an improved optical appearance of the floor.
- The entire coating can be easily removed by basic cleaning. Thus the floors genuine
condition can be restored.
It was found out that the lifetime of coated floorings is about 2-3 times longer than that of non-cared
floorings. This fact makes caring a floor much cheaper, since the costs for the care products on
one hand and the caring procedure on the other hand will not match with the costs arising by
replacing the entire floor.
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Service & Support > Technical files
General Technical Questions Answered
GRANORTE 2009
version: 2009.02 | date: 16-09-2009
CORK UNDERLAYMENT
Cork underlayment is really the only natural material that can perform efficiently for acoustics, heat
and mechanical vibration insulation. It is a good choice for commercial, industrial and residential
use. The cellular honeycomb structure (200 million cork cells per cubic inch) gives this naturally
harvested and renewable material its insulation capabilities and the resiliency property (excellent
compressibility and recoverability). It performs outstandingly under ceramic, marble, hardwood and
laminate flooring.
The main advantages from other types of underlay are:
- It is a non-toxic, natural, environmentally friendly and renewable resource;
- Increases the thermal comfort of the surface floor;
- Lifetime (characteristics do not change with time);
- Provides thermal insulation;
- Do not absorb water;
- Does not support the growth of mold and mildew;
- Provides stress crack protection for ceramic tiles, hardwood floorings and other floor coverings;
Cork underlay in 1/4’’ (6mm) thickness exceeds sound insulation requirements (impact noise) for
condominiums, apartment and office buildings. Even in 1/8’’ (3mm) thickness cork underlayment
will meet the most of the standards for buildings when used with appropriate floor/ceiling assembly
system.
Using a cork underlay of 1/4’’ (6mm) thickness on a concrete slab can improve the overall IIC rating
to about 50 (concrete slab with a fixed rating of 27 dB).
Length of rolls: 50 linear feet (15,2m) or 100 linear feet (30,5m);
Width of rolls: 39’’ (1000mm) or 48’’ (1220mm);
Length of sheets: 36’’ (915mm);
Width of sheets: 24’’ (610mm);
Thickness: 0,12’’ (3mm); 0,16’’ (4mm); 0,2’’ (5mm) or 0,24’’ (6mm);
Density: 11,24-12,49 Lbs per cubic foot (180-200 Kg/m3) or 12,49-13,73 Lbs per cubic foot (200220 Kg/m3);
Cork grain size: 1-2mm or 2-4mm
Packaging: Rolls or sheets.
WHY “HERITAGE” WOOD&CORK INSTEAD OF OTHER VENEERED OR ENGINEERED
WOOD FLOORS?
Looking at GRANORTE’s new line of Wood & Cork floorings (HERITAGE range), you might
wonder what are the differences to the competing engineered wood floors. Of course that our
product is an innovation and nothing alike the standard “I’ve seen that” engineered wood floorings.
However, if you are not a proud owner of a Wood&Cork floor, the differences can be difficult to see:
1 – ENVIRONMENT & SUSTAINABILITY
Our product is using cork – a remarkable sustainable product – and wood. The wood used on the
surface is a veneer of only 0,6mm thickness, this means that we would make almost 7 times more
square metres with the same amount of wood than a standard 4mm veneered engineered floor.
So, in fact we are helping to preserve the forests, using the less wood we can. Furthermore, this
product uses about 40% (by volume) of Post-Industrial recycled content.
Wood&Cork does not use PVC, a petrochemical product that has carcinogen power, cannot be
effectively recycled and produces toxic products during production and incineration.
2 – FINISH
This product uses, probably, the most advanced waterbased factory-applied finish. It is a twocomponent PUR waterborne multi-layer coating system with very high abrasion resistance, high
chemical resistance and exceptional elasticity. It’s easy to maintain with common maintenance
products, has no residual odour (have negligible VOC content) and keeps the wood with its natural
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Service & Support > Technical files
General Technical Questions Answered
GRANORTE 2009
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warm touch. Unlike most of the pre-finished engineered wood floorings that use hard aluminiumoxide finishes or PVC foil, this is a water-based finish, user-friendly, easy to maintain and with an
exceptional natural look-and-feel. A major inconvenience about aluminium-oxide finishes is that
when the floor is going to be sanded the aluminium-oxide dust that will be airborne during the
sanding is a proven lung irritant, and a possible carcinogen. PVC foil finish is absolutely not
recommended because, further than being a hazardous product, it hides all the wood’s natural
beauty.
3 – MICRO-BEVELLED EDGES
The vibrant designs of the natural wood textures are enhanced by the innovative effect of a microbevel along the edges of the plank. Along with the aesthetical aspect of the bevel, it has an
important technical function improving the durability of the floor.
4 – INTEGRATED CORK UNDERLAYMENT
Cork underlayment is really the only natural material that can perform efficiently for sound and
thermal insulation. The cellular honeycomb structure (40 million cork cells per cubic centimetre)
gives cork its insulation capabilities and the resiliency property (excellent compressibility and
recoverability).
The main advantages from other types of underlay are:
- It is a non-toxic, natural, environmentally friendly and renewable resource;
- Increases the thermal comfort of the surface floor;
- Lifetime (characteristics do not change with time);
- Provides thermal insulation;
- Do not absorb water;
- Does not support the growth of mould and mildew;
5 – IMPACT NOISE REDUCTION
Impact noise, is produced when part of the building is directly or indirectly impacted. Energy passes
through the building structure and creates noise in nearby rooms. Examples are heavy footsteps,
banging doors, scraping furniture, vibrations from loud music, and plumbing noise. Floors can have
a big influence in the impact noise insulation. The use of cork, on the surface layer and the
backlayer of this flooring, greatly reduces both impact noise and internal sound reflection (step
sound), contributing for a quieter indoor environment. In fact, when compared with a standard
10mm thickness wood flooring, the reduction of impact noise is more than 17 dB and the step
sound reduction is about 8 dB.
(try tapping the surface of the floor with a hard object and compare the noise with other types of
wood floorings)
6 – INDENTATION AND COMFORT
Resilience is a natural characteristic of cork. So, cork has a natural capacity to recuperate after
static load. On GRANORTE’s Wood&Cork floors the fact that the wood layer is just about 0,6mm
make possible to the surface to behave more like a cork covering, recovering after an indentation
load (furniture legs, high-heels…). This characteristic is responsible for the feeling of comfort when
standing on this floor. The cork layer makes all the difference and the “cushion-effect” cannot be
matched with none of the wood floorings.
7 – REFURBISHING (RE-VARNISHING)
As we have seen, the finish of this product is so advanced that probably it should not be necessary
to re-varnish the floor trough its entire life. Although it may not seem, it is not an advantage to have
an extra hard surface (e.g. laminate, aluminium-oxide) since hardness often also means
brittleness. Elastic coatings are possibly able to resist heavy wear much better and this is the
secret behind our finish. Nevertheless, the floor must be protected and maintained. It was found out
that the lifetime of maintained floorings is about 2-3 times longer than that of non-cared floorings.
This fact makes caring a floor much cheaper, since the costs for the care products on one hand
and the caring procedure on the other hand will not match with the costs arising by replacing or revarnishing the entire floor.
However, the Wood&Cork floors can be re-finished (if you do it with care). Do not be afraid of the
0,6mm thickness veneer, as you should sand only slightly the surface (the old varnish layer), not
the wood itself. Do not use drum or belt sanders but an orbital sander instead. After removing the
dust by vacuuming, apply 2 coats of a recommended water-based varnish.
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Service & Support > Technical files
General Technical Questions Answered
GRANORTE 2009
version: 2009.02 | date: 16-09-2009
8 – SAFETY
We have already talked about the safety features around the finish and the “cushion-effect” of this
product. But that is not all. Wood&Cork floorings are made using high quality raw materials only. All
the chemicals are free of heavy metal, formaldehyde and insecticides/pesticides. The HDF board
used is of the lowest content of formaldehyde and the finish has negligible VOC content. So, the
volatile organic compounds that are expected on installations with these floorings are far bellow the
limits of security and do not put in question the quality of indoor air.
Fire behaviour is rated Euro class Cfl-S1 that is a very good classification as most wood floor are
normally rated Dfl or Efl.
As mentioned, unlike others our product is PVC-free. PVC is dangerous to human health and the
environment throughout its entire life cycle, at the factory, in our homes, and in the trash. When
burning, PVC releases deadly toxic gas.
9 – INSTALLATION
Installation is easy and no other materials are needed. Even some irregularities of the sub-floor are
allowed as the integrated cork underlay will compensate them. If you add all the costs to install
another kind of wood flooring (glued, nailed or even floating) – sub-floor preparation, underlay,
gluing/nailing, time - you will see that the price is not an issue. Another thing that I have to call your
attention is for the fact that every sheet of wood veneer is of the best quality class (we use only
selected sheets); it has of course its cost, but makes installation hassle-free.
10 – EXCLUSIVITY AND OVERALL QUALITY
Yes, this is our advantage too. Sometimes the price is at the same level as standard engineered
wood floors. That can be true, but in the end of the day you will get a product like no other:
- The beauty of natural Wood and the performance of natural Cork;
- Environmentally friendly and eco-responsible;
- Durable, comfortable and safe;
- Thermal and noise insulator;
- Easy installation and maintenance;
- Lifetime structural warranty;
- Exclusive and innovative concept.
The owner of a Wood&Cork floor will be proud to have such an exclusive product and will pay for
the chance to have it.
RADIANT FLOOR HEATING SYSTEM
Cork is normally suitable for under-floor heating. However some care must be taken when applying
the floor (see instructions).
The air pockets in cork make it a great natural insulator and will affect slightly the transmission of
heat. It is normal that a cork floor takes longer to warm up but the heat will be retained more
efficiently.
With radiant heat, heat source is directly beneath the flooring covering which may gain moisture or
dry out faster than in a home with conventional heating system. Cork tiles can be installed as long
as customer understands that joints between tiles could become more visible during heating
season.
The temperature should never be too high as it will give discomfort to feet, it may have influence on
the bond of the adhesive used and it may create discoloration of the floor covering.
It's important that the radiant heating system should be turned on for at least 4-5 days before
installation. New concrete slabs may require longer periods of time.
The floor temperature should be maintained between 20 to 25 °C. Surface temperature should
never be above 28 °C.
It must be taken into account that expansion and contraction of the cork flooring will occur. This is a
natural consequence of changes in interior temperature as well as in the structure’s moisture
content.
GLUED TILES
Thick cork tiles can inhibit transfer of heat to floor surface. 6 mm or thinner cork works best.
The heating should be turned off 2 days before installation starts and must be turned on (in steps)
again not earlier than 3 days after installation.
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Service & Support > Technical files
General Technical Questions Answered
GRANORTE 2009
version: 2009.02 | date: 16-09-2009
Adhesive used for installation of the tiles could lose strength when exposed to high temperatures
(above 26 °C).
Customer should understand that gaps between parquet cork tiles could be visible during heating
season.
FLOATING FLOORS
Floating floors move as a unit since they are not attached to the sub-floor. That means that visible
signs of expansion/contraction take place at the edges of the room.
It is very important that the floor temperature should be maintained during installation at about 25
°C.
SOUND RATINGS, FIRE RATINGS, SMOKE RATINGS;
Acoustical Rating:
Concrete slab 8”
IIC Rating - 58 dB
STC Rating - 56 dB
Cork floor Fire rating (ASTM E-648): Class II
Cork floor Smoke density (ASTM E-662), Flaming: 148 Non Flaming: 272
Reaction to fire (EN 14041; EN 13501-1): Cork tiles Class Cfl – S1; Cork floatings Class Dfl – S1
THERMAL RESISTANCE (R-VALUE)
There is a lot of misunderstanding with Thermal resistance values.
The problem is that the "R-value" is a coefficient mainly used in America with imperial units
2
2
°F.ft .h/Btu (therm.). In European units (SI), the Thermal Resistance is measured in K.m /W. The
relation between these two units is 0,176228. So, given a Thermal Resistance value in SI units,
one should divide for 0,176228 to have the R-value.
The Conductivity (C) of cork floors is known to be about 0,05 W/K.m. The Thermal Resistance (TR)
is the inverse of conductivity for a given thickness (TR=thickness/C). So R-value will be equal to
thickness/0,05/0,176228. If you want a R-value of 1 then thickness=1x0,05x0,176228=8,8mm.
COMPARATIVE R-VALUES OF FLOORING & SUBFLOORS
Material
Typical R-Value R-Value Per Inch Typical Thickness
Cork
1.125
3.00
0.375
Cork/MDF/Laminate
1.175
2.35
0.500
Brick
3.375
2.25
1.500
Recycled Rubber Flooring
1.100
2.20
0.500
Sheet Vinyl
0.200
1.60
0.125
Vinyl Composition Tile (VCT)
0.200
1.60
0.125
Linoleum
0.400
1.60
0.250
Linoleum
0.200
1.60
0.125
OSB
1.050
1.40
0.750
Dense Rubber Flooring
0.250
1.30
0.325
Pine
0.975
1.30
0.750
Fir
0.900
1.20
0.750
Plywood
0.825
1.10
0.750
Softwood
0.825
1.10
0.750
Ceramic Tile
0.250
1.00
0.250
Ash
0.750
1.00
0.750
Maple
0.750
1.00
0.750
Engineered Wood
0.250
1.00
0.250
Engineered Wood
0.375
1.00
0.375
Engineered Wood
0.625
1.00
0.625
Engineered Wood
0.750
1.00
0.750
MDF/Plastic Laminate
0.500
1.00
0.500
Engineered Bamboo
0.720
0.96
0.750
Oak
0.638
0.85
0.750
Marble
0.400
0.80
0.500
Thinset Mortar
0.050
0.40
0.125
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Service & Support > Technical files
General Technical Questions Answered
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NOISE
There are two types of building noise to consider: airborne and structure-borne or impact noise.
Airborne noise comes from common sound sources such as voices, TVs and radios. Rooms with a
lot of hard surfaces can be very noisy as they readily reflect sound. To insulate airborne noise,
sound absorbing materials and insulation techniques should be used in construction of walls, floors
and ceilings (cork is also applied in such systems).
Structure-borne noise, also called impact noise, is produced when part of the building is directly or
indirectly impacted. Energy passes through the building structure and creates noise in nearby
rooms. Examples are heavy footsteps, banging doors, scraping furniture, vibrations from loud
music, and plumbing noise. Floors can have a big influence in the impact noise insulation. Low
density or resilient floor coverings such as carpet or cork floors will greatly reduce both impact
noise and internal sound reflection, contributing for a quieter indoor environment.
So, to reduce the noise that comes from below in a flat, you will need to work much more on the flat
from where the noise comes that on the one you are in. However, it is possible to reduce it on your
flat, but you would need construction work on the walls and floor.
One thing is sure: using cork on floors, you will be creating a better sound environment for yourself
and your neighbours too.
RECYCLED CONTENT
Post-Consumer recycled content
Post-consumer recycling refers to the use of materials that were previously used by consumers.
Packaging: 99%
Post-Industrial recycled content
Post-industrial recycling refers to the use of industrial by-products.
Cork: 100%
MATERIALS COUNTRY OF ORIGIN
MATERIAL
Raw Material
Cork
Chemicals
Binder
Glue
Varnish
Wax
Paint
Pigments
Others
Fibreboard
Packing
Bags and bales
Cartons
Cardboard
Packaging film
Pallets
COUNTRY OF ORIGIN
Portugal, Spain
Portugal, Spain
Portugal, Spain
Portugal, Germany
Portugal, Spain
Portugal, Germany
Germany
Portugal, Spain
Portugal
Portugal
Portugal
Portugal, Germany
Portugal
VOC’s
There is of common known that the floor products from GRANORTE are approved against the
criteria of “Kork-Logo” and “Greenguard”. So, the volatile organic compounds that are expected on
installations with cork floorings are bellow the limits of security and do not put in question the
quality of indoor air.
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Service & Support > Technical files
General Technical Questions Answered
GRANORTE 2009
version: 2009.02 | date: 16-09-2009
PHTHALATES
Phthalates are a family of chemicals that are mostly used as plastic softeners in many different
consumer products, beauty care products and medical devices. So, probably we contact with them
everyday.
It is especially present in PVC (polyvinyl chloride or vinyl) products. Actually, PVC accounts for
about 90% of total phthalate consumption.
We do not use phthalates in our production. Furthermore, our cork products are consistently tested
for phthalates (DMP, DEP, DPP, DBP, DnBP, DiBP) and the result is negative (below detection
level).
CERTIFICATION
GRANORTE is certified ISO 9001:2000. This quality International Standard specifies requirements
for a quality management system where an organization needs to demonstrate its ability to
consistently provide product that meets customer and applicable regulatory requirements, and aims
to enhance customer satisfaction through the effective application of the system.
This Standard is really very interesting and helpful on the development of the organizations, but for
the end-user, the most important issues are related to the product. What really counts is if the
product has its quality certified, its performance according to standard requirements and guarantied
for the expected level of use. For this purpose we have our Specification Data Sheets and the
Declaration of Conformity.
HARMONIZED EUROPEAN STANDARD EN 14041
As the European Union has to guarantee the free circulation of products, and as standardization
cannot impose the abolition of national regulations, it was necessary to harmonize the tools
supporting these regulations within the European Union. The result was the "Construction
Products" Directive (CPD), which actually has two objectives: an economic objective of opening the
market and a consumer-protection objective.
The schedule for the introduction of CE marking on cork-based floor coverings was spring 2006.
Granorte worked together with Portuguese Quality Organization and CEN (on a technical group),
preparing the Harmonized Standard and all the related EN Technical Standards (Specifications and
Test Methods) for resilient floorings and cork. We were one of the first companies with the CE
marking available for cork flooring products.
THIS DOCUMENT IS PROVIDED FOR INFORMATIONAL PURPOSES ONLY. The information contained in this document represents the current view of
GRANORTE on the issues discussed as of the date of publication. Because GRANORTE must respond to change in market conditions, it should not be interpreted to
be a commitment on the part of GRANORTE.
INFORMATION PROVIDED IN THIS DOCUMENT IS PROVIDED “AS IS” WITHOUT WARRANTY OF ANY KIND, EITHER EXPRESS OR IMPLIED. The user
assumes the entire risk as to the accuracy and the use of this document.
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