SlimVac
®
Specification Guide
High performance
vacuum insulation panels
Contents
03
03
04
2
Thermal insulation of buildings
Slimvac product specification
History
Composition and manufacturing
Characteristics
Dimensions and tolerances
Certification
SlimVac Specification Guide
06
08
10
11
12
14
16
Slimvac applications
Facades
Flat roofs and terraces
Ceilings
Floors
Stud walls (timber and metal)
Other applications
Case study
Thermal insulation of buildings
Increasingly demanding regulations covering
the insulation of buildings are imposing much
higher levels of thermal insulation to all
building elements. This leads to more
complicated constructions and increases in
the thicknesses of insulation materials that
need to be incorporated to meet these
requirements.
There is a growing trend to use super-insulating products
like Vacuum Insulation Panels (VIP) in order to limit the
thickness of the construction elements. The reason for doing
so can be aesthetic but in most cases VIPs are used
because there is just not enough space available to install
the required volumes of traditional insulation material.
Furthermore, because super-insulating materials are
lightweight and lower volume, they are significantly easier to
transport and thereby limit the carbon footprint and overall
cost of the building.
SlimVac is a fully certified VIP that has been produced for
several years, following extensive product development and
testing. The calculating value for the thermal conductivity
is certified to be 0.007 W/m.K. The centre of the panel has
a coefficient thermal conductivity of 0.0042 W/m.K, however
it is important to consider the edge effects of the aluminised
foil, therefore we recommend users note the calculating
value above.
SlimVac Specification Guide
3
Slimvac
product
specification
History of vacuum insulation
The first VIP was manufactured in the early 70s and the first
areas of application included refrigeration, cold storage and
the transportation sector.
Soon products and applications for the construction sector
were also designed and developed. Due to the nature of VIP
itself an adapted system has been developed for
construction applications.
VIP composition and how it works
Several VIP compositions are possible but many years of
research and development work has led to the conclusion
that an opacified fumed silica based core, covered by an air
and water vapour tight barrier foil, placed in a vacuum of
around 1 mbar, provides the ultimate insulation product for
long-lasting building applications.
Fumed silica is a microporous material. This means that its
pores are smaller than the mean free path of an air
molecule. Furthermore the thermal conductivity through the
centre panel is so low, that even before it is put under
vacuum, a SlimVac panel has a coefficient thermal
conductivity (λ-value) of less than 0.020 W/m.K.
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SlimVac Specification Guide
Achieving the best λ-values
The largest loss of thermal energy through standard
insulation materials is caused by thermal conduction (due to
the presence of gas molecules). Because of this there is very
little increase in its λ-value over time.
Adding an opacifier to the mix limits the transport of thermal
energy through radiation.
The barrier foil is a highly engineered foil composed of three
metallised (non-aluminium, non heat conductive) polymer
films. No aluminium foil is used in the build up as this would
ruin the intrinsically perfect insulation properties by creating
detrimental thermal bridging along the edges of the panel.
Metallised foils keep these thermal bridges to a minimum.
All these considerations lead to a super insulating product
with a ‘centre-of-panel’ λ-value of about 0.004 W/m.K.
However, building applications last for many years, during
which minor amounts of water vapour and gases enter the
panel reducing the thermal efficiency. Thus, for the
calculation value of the coefficient of thermal conductivity
one has to take into account aging effects as well as the tiny
thermal bridging effect along the edges. These two
considerations lead to a calculating thermal conductivity
value of 0.007 W/m.K for SlimVac.
Characteristics
Dimensions and tolerances
Density
170 – 200 kg/m³
Standard thickness
Compressive strength
160 kPa
SlimVac can be made in every thickness between 10 and 40 mm subject to minimum
order quantities and additional cost.
Internal pressure
< 5 mbar
Coefficient of thermal conductivity
Calculation value including
aging and edge effects
0.007 W/m.K
At the centre of the panel
0.0042 W/m.K
Before being put under vacuum
0.020 W/m.K
Water vapour resistance factor
of the barrier foil
µ = 340.000
10, 15, 20, 25, 30, 40 mm
Standard dimensions
(available on stock)
1300 x 600 mm
1200 x 600 mm
600 x 600 mm
600 x 500 mm*
600 x 400 mm
600 x 200 mm
400 x 300 mm
SlimVac can be made in all
sizes (at additional cost) between
400 mm < length < 1300 mm
200 mm < width < 600 mm
Tolerances
Water vapour diffusion-equivalent 30 m
air layer thickness (sd) or (µd) value
Resistance to moisture of a
non-protected SlimVac
Permanent ambient
relative humidity < 60 %
Resistance to heat
Ambient temperature
< 80°C
Classification for reaction to fire
Core: A1 (EN)
SlimVac panel
B2 (DIN)
Resistance to fire
When SlimVac is integrated in
a construction or a building
element for thermal insulation
reasons, it will largely
contribute to the resistance to
fire of this element.
Length
+2 / - 6 mm
Width
+2 / - 6 mm
Thickness
< 20 mm
20 to 30 mm
> 30 mm
+1 / -1 mm
+1 / -2 mm
+1 / -3 mm
Flatness
5 mm/m
Squareness
5 mm/m
* (not available in 10, 15 and 40 mm thickness)
Composition and manufacturing
Certificates and test reports
A SlimVac panel is composed of a microporous core
wrapped in a microperforated foil and air-tightly vacuum
sealed inside a low permeation barrier film.
• EMPA test report
The core is composed of several components, these include:
• In the process of getting an ETA based on a newly
written CUAP (CSTB-France)
• Zulassung certificate: DIBt
• Fumed silica
• Test report: B2 classification (DIN)
• Opacifier
• Test report: FIW München
• Organic reinforcing fibres
This powdery blend is compressed to a block with a density
ranging from 170 to 200 kg/m³.
ISO and CEN are in the process of writing an ISO / EN
standard on Vacuum Insulation Panels.
To avoid dust from the core material being deposited onto
the area where the barrier foil is sealed, a microperforated
foil is wrapped around the core.
This composite is inserted in a pouch made of barrier foil
and sealed in an environment where the pressure is reduced
close to 1 mbar.
Such a barrier foil is a highly sophisticated composite of
three metallised polymer films lined at one side with a Linear
Low Density Polyethylene sealing layer. This last layer is
used to create a welded seam.
SlimVac Specification Guide
5
Slimvac
applications
Facades
A variety of facade systems can use
SlimVac as the insulation element:
• Ventilated rainscreen cladding
• Brick cavity walls
• EWI
• Integral lightweight stud walls
(see page 12)
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SlimVac Specification Guide
Benefits
• Minimal thickness of insulation layer with maximum
performance.
• Double layer application: minimises the effect of the
thermal bridges caused by the timber battens.
Ventilated rainscreen cladding
In this type of application, the SlimVac panels must be
protected against rain or high relative humidity. Therefore
encapsulated SlimVac is used.
Between the different layers of SlimVac panels high density
PU strips can be inserted. In this way, thermal bridging is
limited to a minimum and the timber batten carrying the
lining board can be fixed in the load bearing wall without
damaging the SlimVac.
Example shows Cedral Weatherboard.
Brick cavity wall
For this type of construction, encapsulated SlimVac must
be used. The cavity wall anchors should be carefully fixed
through the joints between the SlimVac panels.
Rendered external insulated (ETICS)
Again encapsulated SlimVac panels must be used.
They are fixed using PVC profiles and finished with an
appropriate exterior rendering system.
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Flat roofs and terraces
General description
1 Watertight roof finishing
1
2
2 PUR / PIR protection layer
3
4
3 SlimVac
4 Protective layer
5 Vapour barrier
6 Concrete roof
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SlimVac Specification Guide
5
6
Existing flat roofs are, in most cases poorly
insulated. When they require upgrading to
the new national building standards for roof
insulation, thick layers of traditional insulation
may be required.
This however creates detailing problems:
1 The distance between the watertight finishing of the
perimeter wall and the top of the roof finishing must
be ≥ 150 mm.
2 Detailing around skylights.
3 Detailing around pipes penetrating the roof.
4 When the roof is linked to a cavity wall, the distance
between the water drainage layer in that cavity wall and
the top of the roof finishing must be ≥ 150 mm.
There are many arguments for using SlimVac in such
applications. In the worst case, when no space at all is
available for extra insulation, one can replace the existing
insulation with a layer of SlimVac. In most cases a thin
SlimVac layer can be added to the existing roof
construction.
In this way, the total cost of the project can be lower than
the use of additional thicker layers of traditional insulation
materials with the additional construction detailing issues,
which can increase costs.
Newly built insulated flat roofs can be designed in such a
way that thick layers of traditional insulation materials can
be incorporated.
However, if the new roof requires a gutter to be added, in
most cases this would be carried out by locally reducing the
thickness of the applied insulation layer, potentially creating
a thermal bridge in that area. This can be avoided by using
SlimVac® for the new gutter construction.
Benefits
• Minimal thickness of insulation layer with maximum
performance.
• Building regulations can limit the height of certain floor
levels – with SlimVac one can still meet the thermal
insulation requirements.
• No increase to the height of the perimeter wall in
case of renovation, which, in certain cases is not
permitted by local building regulations.
• No requirement to change the level of the water drainage
layer in a cavity wall.
• No need to dismantle and adjust the height of the
connection of the skylights.
SlimVac Specification Guide
9
Ceilings
When there is a non-heated space under an inhabited area,
the floor should be highly insulated to limit the downwards
loss of heat. Insulating a floor can create structural and
height issues, especially in the case of renovation. It would
be much easier to insulate the ceiling in the area below but
in many cases there is too little space available. For
instance, the space below could be a garage, a cellar or
completely open accessible area under the house.
In such cases, the solution is to fix timber battens to the
soffit and to insert SlimVac in between the battens and to
use a fibre cement sheet as a lining board protecting the
SlimVac panels. The SlimVac panel size will dictate the
batten spacing.
Benefits
• Minimal thickness of insulation layer with maximum
performance.
• Ideal for limited height in garages under apartments.
Technical data for insulated concrete floor (300mm thick)
Thickness of
concrete floor
Thickness of
SlimVac
Thickness of
FC sheet
Rt-value
U-value
(W/m3.K)
Rt-value
Thermal bridge
incl
(m2.K/W)
U-value
Thermal bridge
incl
(W/m3.K)
(mm)
(mm)
(mm)
(m2.K/W)
300
20
12
3.16
0.32
2.16
0.46
300
30
12
4.59
0.22
2.88
0.35
300
40
12
6.02
0.17
3.54
0.28
General description
1 (Concrete) floor
1
2 Timber batten
3 SlimVac
4 Lining board
2
3
4
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SlimVac Specification Guide
Floors
On smooth timber or concrete bases
Composition:
• Protection layer (e.g. 3 mm PE foam)
• SlimVac
• Protection layer (e.g.: 3 mm PE foam)
• Finishing: Dry finishing board, traditional screed
On uneven bases
Composition:
• Protection layer (e.g.: 3 mm PE foam)
• SlimVac
• Protection layer (e.g.: 3 mm PE foam)
• Finishing: Dry finishing board, traditional screed
Benefits
• Minimal thickness of insulation layer with maximum
performance.
• Potential consequences of raising floor height on: door
dimensions, steps, ducting and wiring, level of radiators
are all reduced by using SlimVac.
SlimVac Specification Guide
11
Stud walls (timber and metal)
General description
A light weight exterior wall can be
metal frame or a timber frame
construction.
7
4
1 Exterior wall finishing (e.g.
brick wall, light facade cladding)
4
3
2
2 Cavity
3 Exterior lining board
(e.g. Duripanel)
4 Additional standard insulation
5 SlimVac
6 Metal or timber stud
7 Interior lining board
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SlimVac Specification Guide
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5
1
In order to meet increased thermal
requirements, external lightweight
walls are becoming thicker and thicker.
Traditionally, external stud walls were constructed to
withstand wind pressures, however with the development
of thermal building regulations, the thicknesses of the stud
walls have become increasingly governed by the thickness
of the insulation. Traditional insulation materials such as
mineral wool, can increase the width of the profile by up
to 220mm plus. However when using SlimVac in the
middle of the cavity, the thickness of the wall can be
reduced significantly.
The advantage of locating SlimVac at the centre of the cavity
is that it will not be damaged by the through fixing of the
lining boards to the metal studs. Additionally, light objects
(paintings, pictures, etc.) can be fixed to the wall without
perforating the SlimVac board.
A downside to this type of construction is that the
supporting frame (typically metal frame) acts as a thermal
bridge. This can be avoided by inserting a compressionresistant insulation material (e.g. high density PU) between
the stud and the exterior lining board. An alternative exterior
finish is EWI (External Wall Insulation) with a thinner
insulation layer.
Compression resistant thermal
insulation and rendered external
insulated (EWI)
These stud wall systems can be used for the construction
of new buildings but also for the renovation of existing
constructions. When, for example, apartment blocks are
renovated, the complete facade can be replaced with
in-situ built or (partially) prefabricated facade elements
that are designed to meet the new requirements for
thermal insulation.
Benefits
• Minimal thickness of insulation layer with maximum
performance.
• Limited transport cost for prefabricated elements.
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Other applications
Window reveals
Window reveals are an ideal area of application for SlimVac.
They can be an important thermal bridge and in most cases,
there is insufficient space to apply the required thickness of
traditional insulation materials.
It is recommended that a SlimVac panel with a facade
cladding board is fixed directly to the wall by means of glue
and mechanical fixing where possible.
Benefits
• Minimal thickness of insulation layer with maximum
performance.
Curtain walls
Curtain wall systems require, in addition to the glazed
elements, non-glazed components at each floor level.
Commonly, sandwich panels are used for these areas.
In order to optimise the thermal insulation performance
whilst using thin panels that can be incorporated into the
curtain wall frame, SlimVac is bonded in between an exterior
and an interior lining board.
Benefits
• Minimal thickness of insulation layer with maximum
performance.
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SlimVac Specification Guide
Pitched roofs – interior roof insulation
Renovating the roof from the inside allows the use of
SlimVac to maintain the maximum room space.
Timber battens can be fixed below the existing roof
structure at the required depth for the insertion of SlimVac.
After fixing a vapour barrier over the total surface, a lining
board is fixed across the battens.
Benefits
• Minimal thickness of insulation layer with maximum
performance.
SlimVac Specification Guide
15
Case study
Project:
Promat Business Centre
Applications: Flat roof and facade
SlimVac Vacuum Insulation Panels (VIP) were used at the
Promat Business Centre as an insulation measure during
its renovation. Once installed the flat roof and facade
achieved U-values of 0.13 W/m2K and 0.16 W/m2K
respectively. The building consists of:
• Meeting room for 60 people that can be divided in to
3 smaller meeting rooms
• Video conference room
• Training room
• Foyer
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SlimVac Specification Guide
Flat roof
Facade
Surface
+/- 250 m²
Surface
Front side +/- 45 m²
Composition:
Concrete support
Vapour barrier
5 mm PE foam
40 mm SlimVac
40 mm PIR
Pressure spreading layer
Bituminous watertight layer
Ballast: granulates
Composition
10 mm plaster rendering
140 mm brick wall
8 mm PE foam
40 mm SlimVac between timber battens
Breather membrane
Timber battens
Equitone Tectiva
U-value
0.16 W/m²K
U-value
0.13 W/m²K
Slope of roof surface
2%
Other
2 drainage holes
SlimVac Specification Guide
17
Call
Email
Or visit
on 01283 722588
at info@marleyeternit.co.uk
www.marleyeternit.co.uk/slimvac
Marley Eternit Limited, Lichfield Road, Branston, Burton-on-Trent, DE14 3HD